Field of the Invention
[0001] The present invention relates to a method of cleaning a fabric material using optical
energy. More particularly, the invention is concerned with using optical energy to
clean fabric material, including the combined use of optical energy and cleaning agents
to enhance cleaning, such as, for example, enhancing stain removal.
Background
[0002] Conventional cleaning apparatus and processes typically utilise an aqueous method
or a method which utilises chemicals. Consider, for example, household washing machines
or dry cleaning, which is more commonly used within industrial cleaning processes.
[0003] Domestic cleaning of clothes or other fabric articles typically involves hand washing
processes or more commonly front or top-loaded drum-style washing machines which employ
both an aqueous and mechanical cleaning process, often requiring large amounts of
detergents and stain removal chemicals. Such machines have a high consumption of both
water and power, with an average domestic washing machine using between 9-10 litres
of water and consuming approximately 0.75 KW-hour electricity per wash load. Once
the items are cleaned, the very nature of the cleaning process leaves the articles
quite wet and requires subsequent drying, either in an inefficient machine such as
a commercial tumble drier or through inefficient use of a building's heating system
(radiators, etc.) or through outside drying via direct sunlight and / or wind.
[0004] Dry cleaning processes typically involve extensive use of hydrocarbon solvents such
as perchloroethylene, and the storage, treatment and disposal of such chemicals may
pose environmental concerns. Furthermore, dry cleaning equipment is specialized and
is often extremely expensive and non-portable.
[0005] The cleaning of carpets and upholstery, both in the domestic as well as industrial
environment, typically uses hot water or steam processes and, in many cases, these
processes again leave the material soaked to dry out gradually over time. For industrial
applications, for example in the transport sector where seats of passenger aircraft,
trains and buses require regular cleaning, this can involve periods of "down time"
where the vehicle is not used so as to allow the cleaned upholstery to dry.
[0006] In modern society, many articles being cleaned using conventional method and apparatus
are very lightly or locally soiled. For example, a shirt may have a dirty collar and
cuffs and perhaps have an odour in certain regions of the shirt. Nevertheless, the
item is fully washed simply because there is a small oil or food stain in a very localised
area. In a household setting, the use of a washing machine to clean such items on
a daily basis can be excessive, and can result in degradation of the lifetime of the
article due to the mechanical nature of the cleaning process and the need, very often,
for drying of the garment in direct sunlight.
[0007] US 4987286A describes a method and apparatus for removing minute particles (as small as submicron)
from a surface, such as an optical surface and a semiconductor substrate. An energy
transfer medium is interposed between each particle to be removed and the surface
to which the particles are adhered. The medium is irradiated with laser energy at
a wavelength which is strongly absorbed by the medium. The medium absorbs sufficient
energy to cause explosive evaporation with sufficient force to dislodge the particles.
US 2001/0011545 A1 describes a laser cleaning process for semiconductor material and the like. The process
comprises applying a liquid to a surface of a semiconductor wafer to be cleaned, performing
a controlled spin to leave a controlled amount of liquid, a residual layer, on the
surface and irradiating the surface with laser radiation to cause explosive evaporation
of the residual layer of liquid, to remove contaminant particles from the surface.
Belli, R et al (DOI: 10.1007/ S00339-006-3530-3) discloses a method of laser cleaning
artificially aged textiles.
Summary of the Invention
[0008] Accordingly, there is provided a method as detailed in claim 1. Advantageous features
are provided in the dependent claims.
[0009] In consideration of one or more of the disadvantages with conventional cleaning methods
and apparatus, the present inventor has devised novel processes for cleaning fabric
materials. One or more of the amount of water, steam and/or chemicals, as well as
the electrical power, used within prior art methods can in many instances be significantly
reduced.
[0010] Methods and apparatus for cleaning a fabric material (including a "practical" fabric
material, as defined below), are disclosed, involving the application of optical energy
to the fabric material, typically in the form of a beam of light, where the energy
of the beam causes cleaning of the contaminant, such as a stain, from the fibers of
the fabric material. The cleaning may occur via any mechanism, including one or more
of, alone or in any combination, ablation, melting, heating or reaction with the fabric
material or contaminant or agent introduced to aid in the cleaning. For example, stain
removal can include reaction with the particular contaminant to change the visibility
of the contaminant. The optical energy is typically applied to a selected area of
the fabric material (e.g., as a beam), and the fabric material and beam moved relative
to one another so as to clean a larger area of the fabric material, either by moving
the fabric material or the beam, or both. Movement of the beam with respect to the
fabric material can be attained through a beam scanning mechanism or through movement
of the optical source itself. The optical energy can be applied to one surface of
the fabric material or, if both surfaces are accessible, multiple surfaces can be
exposed to the optical energy to enhance the cleaning depth within the fabric material.
[0011] By way of example and not limitation, contaminants to be cleaned can be one or more
of (or any combination of) dirt particles, molecules and particles chemically bonded
to textile fibers, bodily fluids, food stains and food substances, bacteria and odour-inducing
particles and molecules or substances, oils, greases, biological materials, and nuclear
particles. Contaminants can be organic or inorganic, or combinations of both organic
and inorganic materials.
[0012] The optical energy is preferably delivered to the fabric material as a beam. The
beam of light can be divergent, providing a broad area of illumination or can be collimated
or focused to a much more confined region of the substrate using appropriate beam
shaping and/or focussing optics. The focused or collimated beam can be in any shape
but would preferably be in the form of a spot or a stripe. The optical energy can
be in the form of a narrow spectral band, several different narrow spectral bands,
or can be broadband and comprise many wavelengths of light in a continuum spectrum
(e.g., the source of optical energy can comprise a supercontinuum source). The optical
energy can comprise a wavelength selected to clean a specific contaminant from a substrate.
The source of optical energy can comprise a wavelength-filtered light source and can
further allow for the selection of a particular wavelength to achieve optimized contaminant
cleaning dependent on the contaminant and/or fabric material make-up.
[0013] Methods of the invention can include steps or be adapted for assisting the cleaning
of the contaminant from the fabric material, such as helping extract the contaminant
(e.g., via chemical action), blowing away the contaminant or providing an activation
mechanism to the contaminant cleaning process. For example, water can be introduced
to dampen the contaminated fabric material, steam to provide heat, moisture or pressure
to the cleaning process, vacuum or compressed air to provide removal of mobile cleaned
contaminant particles through suction or by blowing the contaminant away from the
fabric material. Cleaning agent chemicals, including detergents, stain removers, oxygen
based bleaching agents, enzymes, surfactants and anti-oxidants, may provide a chemical
reaction to assist the removal of the contaminant or stain, such as from the fibers
of a fabric material. When applying a liquid such as water or a cleaning agent such
as a detergent solution, it is preferable to replenish the cleaning agent regularly
to extract removed contaminant from the region of the fabric material being cleaned,
thus preventing re-absorption and re-staining of the material. This is best achieved
using a flow of the solution or liquid, including a flow for applying the cleaning
agent to the fabric material and a flow of soiled cleaning agent being removed from
the fabric material.
[0014] The cleaning agent solution used to assist the cleaning process is preferably particularly
adapted for use with a given optical source and for cleaning a given contaminant.
For example, the chemical may have an additive which has increased absorption of the
optical energy from the light source, thus enhancing the efficiency of localised heating
within the fabric. This additive is selected to have optical absorption at one or
more wavelengths of the given optical source. The additive may have no other substantial
function.
[0015] Alternatively, the cleaning agent chemical used to assist the optical cleaning process
may be an existing commercial product such as a household laundry detergent or stain
remover, but, when used with an optical source or apparatus according to the present
invention, has improved cleaning or stain removal capability or can achieve the cleaning
without conventional high temperature aqueous laundry processes. The optical energy
from the optical source provides localised heat which increases the effectiveness
of the chemical cleaning agents such as detergent, enzyme or bleaching agent. The
optical energy can also increase the mobility of the contaminant molecules making
them easier to react with the chemical and remove from the fabric.
[0016] Methods of the invention can include steps or be adapted for sensing the speed of
translation of the beam with respect to the fabric material and controlling the speed
and the optical energy dosage delivered to prevent over exposure and damage of the
fabric material, as well as, additionally or alternatively, interlocking the source
of optical energy (e.g., laser source) such that it is made very difficult to operate
the source whilst potentially exposing the skin and/or eyes of the a user to the optical
radiation. The appliance can include a motion detector to sense motion of the beam
and/or the appliance from which the beam is delivered to ensure that one local region
of the material being cleaned or ironed is not continually exposed to the optical
energy or exposed to an undesired dosage of optical energy, resulting in degradation
or damage locally to the material. The motion detector would preferably be interlocked
to the optical source to switch off the source or reduce its intensity in the event
that the appliance motion slows or stops, and this could be effected via appropriate
configuration of a processor in control of the source of optical energy, or an optical
conditioning apparatus (e.g., an attenuator or modulator or beam deflector) in the
optical path used to deliver the beam to the fabric material, as well as in communication
with the appropriate motion or other sensors. The type or nature of the fabric material
can be sensed as well as the rate of removal and type of removed contaminant, such
that automated scanning and power delivery of the light beam can be incorporated into
the methods or apparatus of the cleaning invention, such as via the configuration
of the processor and apparatus.
[0017] Alternatively, a cleaning appliance processor can be programmed according to the
type or brand of fabric being cleaned, the contaminant being cleaned, the type or
brand of detergent being used or any combination of these parameters, to control characteristics
or parameters of the optical beam or of the cleaning process (e.g., the type or delivery
of a cleaning agent).
[0018] The programmable appliance presents an upgradable solution to cleaning, whereby improvements
in fabrics, detergents and cleaning processes become available to a user of the appliance
which can be upgraded through communication with the processor of new data or a software
or firmware upgrade of the appliance. In this instance, the appliance can include
an on-board processor and means for inputting, such a data transfer interface, and
possibly outputting data from the appliance. The appliance can include a USB or Ethernet
or any other type of input/output communications port.
[0019] The upgrade to the appliance in the process parameters can be achieved by downloading
processes from the internet, this process information being provided by the manufacturers
of the textile, clothing items, detergent, the appliance itself or from other users
of the appliance.
[0020] Specific process parameters can alternatively be communicated to the programmable
appliance through, for example, a bar-code scan or any other form of upload. Process
parameters provided with the fabric or detergent can also be manually entered into
the appliance. For example, a method may be introduced whereby new laundry detergents
and cleaning products have a "scanable" process optimisation, proven in the manufacturer's
laboratory to improve the process, either through improved cleaning quality or through
reduced energy inputs, lower temperature cleaning requirements or other improvement
parameters. The appliance can have a built-in processor and scan mechanism which enables
the processes to be optimised for use with the new or different cleaning product.
The same can be true for a new garment or textile which can have optimum cleaning
parameters included on, for example, a label within the garment or textile. The cleaning
process is then modified such that the textile is cleaned more efficiently or the
lifetime of the textile is enhanced due to reduced wear from the cleaning process.
The programmable appliance therefore provides a means for optimising cleaning of textiles
based on the improvements in textiles, detergents and user experience.
[0021] The foregoing features noted herein, such as above, regarding the use of a processor
and control of the cleaning process via communication of new data or software or firmware
to the processor or appliance, such as information relating to a fabric material to
be cleaned, is not limited to use with cleaning processes using optical energy, but
can be applied to conventional washing or cleaning or other procedures, such as in
conventional washer, dryer, dry cleaner or pressing process, where cleaning agent
type, wash cycle, temperature, characteristics could be controlled or specified responsive
to a processor receiving data from, for example, a bar code or other machine readable
data element associated with the fabric material, such as by being affixed to, printed
on, of otherwise integrated with the fabric material, such a textile.
[0022] Generally speaking, typically the make-up of a cleaning agent will comprise one or
more of a surfactant, enzyme, oxygen-based bleaching agent, water softener, anti-redeposition
agent or optical brightener. Preferably the chemical will contain an oxygen-based
bleaching agent such as Sodium Percarbonate whose stain removal properties are enabled
or enhanced by the optical energy absorbed locally within the fabric material. The
detergent or stain remover chemical can contain less than 5% of the oxygen-based bleaching
or oxidizing agent. The detergent or stain remover chemical can contain more than
5% of the oxygen-based bleaching or oxidizing agent. The stain remover can contain
more than 15% of the oxygen-based bleaching or oxidizing agent. The stain remover
can contain more than 30% of the oxygen-based bleaching or oxidizing agent. The liquid
can comprise a solvent selected to clean a contaminant from the fabric material. Percentages
can be by weight.
[0023] A chemical (cleaning agent, such as a stain remover) is applied to the fabric material
during the optical cleaning process, such chemical is preferably applied in the form
of a liquid or solution. The solution can be applied to the fabric material as a stream,
spray or mist. The solution can be applied to the fabric material once prior to carrying
out the optical cleaning process. During the cleaning process, the fabric material
can be substantially immersed in the solution. During the optical cleaning process,
the solution can be continually or repeatedly applied to the fabric material as a
spray or flow, enabling the solution to be replenished. During the continual or repeated
application of the solution to the fabric material, there is preferably a removal
process where previously applied solution can be cleaned from the fabric material
area, said previously applied solution having been used to remove stain or contaminant
molecules from the fabric material and hence said previously applied solution containing
removed stain or contaminant molecules.
[0024] A method of cleaning a fabric material can involve the use of optical energy with
an existing or developed commercial cleaning agent such as a detergent or stain remover,
said combination of the cleaning agent and optical energy providing one or more of
an enhanced cleaning performance, enhanced stain removal, more efficient cleaning
or stain removal process, more convenient cleaning or stain removal process or more
environmentally friendly cleaning or stain removal process.
[0025] A method of upgrading the performance of a fabric material cleaning process can involve
modifying the parameters of the cleaning process automatically by importing cleaning
parameters into a processor controlled cleaning appliance, the cleaning parameters
being optimised for a given cleaning agent, type of fabric, brand of fabric or cleaning
agent, or through improved understanding of the performance of the cleaning appliance
through continued experience.
[0026] More detailed aspects and embodiments are now described below. However, any of the
features of the foregoing broad aspects, as well as those described in more detail
below, taken alone or in combination, can apply to any of the embodiments or aspects
described herein, except where features are clearly mutually exclusive or explicitly
stated to be incompatible.
[0027] In one aspect of the invention, there is provided a method of cleaning a fabric material
with optical energy as per the subject-matter of claim 1, comprising applying cleaning
agent to the fabric material; and applying optical energy from a source of optical
energy to the fabric material having the cleaning agent applied thereto, the optical
energy having one or more optical parameters selected for cleaning the fabric material.
[0028] The cleaning agent can comprise a bleaching agent. The cleaning agent can comprise
an oxidizing agent. The cleaning agent can comprise, in various practices of the invention,
at least 5% by weight of the oxidizing agent; at least 10% by weight of the oxidizing
agent; at least 15% by weight of the oxidizing agent; at least 20% by weight of the
oxidizing agent; or at least 25% by weight of the oxidizing agent.
[0029] The source of optical energy can comprise a laser. The source of optical energy can
comprise a plurality of lasers. The source of optical energy can comprise a plurality
of diode lasers.
[0030] Applying the optical energy can comprise applying the optical energy so as to heat
one or both of the cleaning agent or at least a portion of the fabric material to
a temperature of, in various practices of the invention, at least 40 degrees Celsius;
at least 50 degrees Celsius; or at least 60 degrees Celsius. Applying the optical
energy can comprise applying the optical energy so as to heat the cleaning agent to
a temperature of, in various practices of the invention, at least 40 degrees Celsius;
at least 50 degrees Celsius; or at least 60 degrees Celsius. Applying the optical
energy can comprise applying the optical energy so as to heat at least a portion of
the fabric material to a temperature of, in various practices of the invention, at
least 40 degrees Celsius; at least 50 degrees Celsius; or at least 60 degrees Celsius.
[0031] The method can comprise removing, after the step of applying optical energy to the
fabric material having the cleaning agent applied thereto, cleaning agent from the
fabric material. The method can comprise applying, subsequent to the removal of cleaning
agent, additional cleaning agent to the fabric material.
[0032] The optical energy having one or more optical parameters selected for cleaning the
fabric material can comprise the optical energy having a peak power of, in various
practices of the invention, no greater than 1 kW; no greater than 500 W; or no greater
than 100 W. The optical energy having one or more optical parameters selected for
cleaning the fabric material can comprise the optical energy having a duty cycle of,
in various practices of the invention, no less than 10%; no less than 20%; no less
than 40%; or no less than 75%. The optical energy having one or more optical parameters
selected for cleaning the fabric material comprises the optical energy comprising
CW optical energy.
[0033] The cleaning agent can comprise an absorbing agent for enhancing absorption of the
optical energy by the cleaning agent. The absorbing agent can otherwise be substantially
inactive in relation to the cleaning process. The absorbing agent can substantially
increase the optical absorption of the cleaning agent.
[0034] There is also described a method of cleaning a substrate using optical energy, comprising
reading data from a data bearing element associated with a substrate to be cleaned;
communicating the data to a processor associated with a cleaning appliance comprising
a source of optical energy; and applying optical energy from the source of optical
energy of the cleaning appliance to the substrate for cleaning the substrate, wherein
the processor, responsive to the communicated data, controls the cleaning of the substrate
with the optical energy.
[0035] The data bearing element can be integral with the substrate. The data bearing element
can comprise machine readable modifications of the substrate, such as, for example,
machine readable printing on the substrate. The data bearing element can comprise
a bar code. The data bearing element can comprise a radio frequency identification
(RFID) tag.
[0036] The processor, responsive to the communicated data, can control one or more of, in
any combination, the delivery of a cleaning agent to the substrate; the removal of
cleaning agent from the substrate; or one or more characteristics of the optical energy
applied to the substrate. The processor can control the characteristic of the optical
energy comprising the duty cycle of the optical energy. The processor can control
the characteristic of the optical energy comprising the optical power of the optical
energy. The processor can control the characteristic of the optical energy comprising
the pulse duration of the optical energy.
[0037] Reading the data can comprise machine reading of the data, such as reading the data
with an electro-optical device, such as a bar code scanner or wireless device.
[0038] There is disclosed a cleaning appliance for cleaning a substrate, comprising an appliance
body comprising an aperture for emanating optical energy for cleaning the substrate;
an optical transmission pathway arranged for propagating optical energy received from
an optical energy source to said aperture for emanation of the optical energy for
the cleaning; a processor; a data interface in communication with the processor; wherein
the laser cleaning appliance is configured such that the processor can output signals
that can control the cleaning of the substrate by the laser cleaning appliance; and
wherein the processor is configured for controlling, responsive to data received by
the data interface and via the output signals, the cleaning of the substrate.
[0039] The cleaning appliance and processor can be configured such that the processor can
control the cleaning of the substrate by controlling one or more characteristics of
the optical energy emanated by the aperture, such as, for example, the characteristic
of the optical energy comprising the duty cycle of the optical energy; the characteristic
of the optical energy comprising the optical power of the optical energy; or the characteristic
of the optical energy comprising the pulse duration of the optical energy.
[0040] The cleaning appliance can be adapted and constructed for delivering a cleaning agent
to the substrate and wherein the laser appliance and processor are configured such
that the processor can control the cleaning of the substrate by controlling the delivery
of the cleaning agent to the substrate. The laser cleaning appliance can be adapted
and constructed for removing cleaning agent from the substrate and wherein the laser
appliance and processor are configured such that the processor can control the cleaning
of the substrate by controlling the removal of cleaning agent from the substrate.
[0041] The cleaning appliance can comprise the source of optical energy, the source of optical
energy being disposed within said appliance body, and wherein the laser appliance
and processor are configured such the processor can control the cleaning of the substrate
by controlling the operation of the source of optical energy.
[0042] There is further disclosed a cleaning appliance for cleaning a fabric material, comprising
an appliance body comprising an aperture for emanating optical energy for cleaning
the fabric material; an optical transmission pathway arranged for propagating optical
energy received from an optical energy source to said aperture for delivery of the
optical energy to the fabric material for the cleaning; and wherein said appliance
is adapted and constructed for delivering a cleaning agent to the fabric material.
The appliance can be adapted and constructed for delivering the cleaning agent to
an area of the fabric material on which the optical energy emanating from the aperture
is incident.
[0043] The cleaning appliance can comprise a work surface arranged such that said work surface
is in physical contact with the fabric material during cleaning of the fabric material.
The laser cleaning appliance can comprise a suction pump for removing material from
the fabric material.
[0044] The source of optical energy can comprise a laser. The cleaning appliance can comprise
the source of optical energy. The source of optical energy can be disposed within
said appliance body. The source of optical energy can be arranged such that it is
portable with the appliance body. The source of optical energy can comprise a plurality
of lasers. The source of optical energy can comprise a plurality of laser diodes.
[0045] The cleaning appliance can be adapted and constructed such that the optical energy
emanated by said aperture has a peak power of, in various practices of the invention,
no greater than 1 kW; no greater than 500 W; or no greater than 100 W. The laser cleaning
appliance can be adapted and constructed such that the optical energy emanated by
said aperture has, in various practices of the invention, a duty cycle of no less
than 10%; no less than 20%; no less than 40%; or no less 75%.
[0046] The cleaning appliance can comprise cleaning agent. The cleaning agent can comprise
an oxidizing agent. The cleaning agent can comprise, in various practices of the invention,
at least 5% by weight; at least 10% by weight; at least 15% by weight; at least 20%
by weight; or at least 25% by weight of the oxidizing agent.
[0047] There is also described a cleaning appliance for cleaning a substrate, comprising:
an appliance body comprising an aperture for emanating optical energy for cleaning
the substrate; an optical transmission pathway arranged for propagating optical energy
received from an optical energy source to said aperture for emanation of the optical
energy for the cleaning; and wherein said laser cleaning appliance includes a suction
pump for removing material from the substrate.
[0048] The cleaning appliance can comprise a work surface arranged such that said work surface
is in physical contact with the substrate during cleaning of the substrate. The source
of source of optical energy can comprise a laser. The laser cleaning appliance can
comprise the source of optical energy, the source of optical energy being disposed
within said appliance body. The source of optical energy can comprise a plurality
of lasers. The source of optical energy company can comprise a plurality of laser
diodes.
[0049] The cleaning appliance can be adapted and constructed such that the optical energy
emanated by said aperture has a peak power of, in various practices of the invention,
no greater than 1 kW; no greater than 500 W; or no greater than 100 W. The laser cleaning
appliance can be adapted and constructed such that the optical energy emanated by
said aperture has, in various practices of the invention, a duty cycle of no less
than 10%; no less than 20%; no less than 40%; or no less 75%.
[0050] The method may also comprise slidingly contacting the substrate with a work surface,
said work surface comprising an aperture; and emanating optical energy from the aperture
for cleaning the substrate.
[0051] A number of yet additional aspects of the invention, including methods, are now presented
in more detail. Again, any of the features of the foregoing aspects, as well as those
described in more detail below, taken alone or in combination, can be included in
any of the embodiments or aspects described herein, except where features are clearly
mutually exclusive or explicitly stated to be incompatible.
[0052] A portable cleaning appliance can comprise an appliance body comprising an aperture
for emanating optical energy for cleaning and an optical transmission pathway arranged
for propagating optical energy received from an optical energy source to the aperture
for emanation of the optical energy for the cleaning. The portable cleaning appliance
can be adapted and constructed so as to be hand held and for cleaning a fabric material,
including cleaning by emanating from the aperture the optical energy having one or
more optical parameters selected so as to clean a selected contaminant from the fabric
material. The portable cleaning appliance can include a work surface arranged such
that the work surface is in physical contact with the fabric material during cleaning
or, alternatively or additionally, the portable cleaning appliance can be arranged
and constructed such that that the cleaning with the optical energy is blind as to
the user holding the cleaning appliance in their hand for cleaning. As an alternative
to the cleaning being blind as to the user, the appliance can include a viewing window
that allows the user at least some visibility of the cleaning process, wherein the
cleaning appliance filters a selected wavelength or wavelengths to reduce harmful
exposure of a user of the portable cleaning appliance to the selected wavelength or
wavelengths.
[0053] The portable cleaning appliance can include the work surface arranged such that the
work surface is in physical contact with the fabric material during cleaning. The
portable cleaning apparatus can be arranged and constructed such that that the cleaning
with the optical energy is blind as to the user holding the cleaning appliance in
their hand for cleaning. The portable cleaning appliance can be constructed and arranged
so as to include a viewing window that allows the user at least some visibility of
the cleaning process wherein the cleaning appliance filters a selected wavelength
or wavelengths to reduce harmful exposure of a user of the portable cleaning appliance
to the selected wavelength or wavelengths.
[0054] The portable cleaning appliance can include the work surface arranged such that the
work surface is in physical contact with the fabric material during cleaning and the
cleaning is blind as to the user holding the cleaning appliance in their hand for
cleaning. The portable cleaning appliance can include the work surface arranged such
that the work surface is in physical contact with the fabric material during cleaning
and can be constructed and arranged so as to include a viewing window that allows
the user at least some visibility of the cleaning process wherein the cleaning appliance
filters a selected wavelength or wavelengths to reduce harmful exposure of a user
of the portable cleaning appliance to the selected wavelength or wavelengths.
[0055] The work surface can substantially surround the aperture. The work surface can be
adapted for contacting and surrounding the fabric material such that substantially
no stray optical energy escapes from the cleaning process when the contact is maintained
with the fabric material. The portable cleaning appliance can include a proximity
sensor arrangement for providing control of the emanation of optical energy for cleaning
from the aperture responsive to the proximity of the fabric material to the aperture.
The portable cleaning apparatus can be adapted and constructed such that substantially
no optical energy for cleaning emanates from the aperture unless selected physical
contact is maintained between the surface and the fabric material.
[0056] A portable cleaning appliance can be adapted and constructed such that it only operates
to clean the fabric material when oriented substantially horizontally. The portable
laser appliance can be adapted and constructed for delivering a vapour to the fabric
material. The vapour can comprise steam. The portable laser apparatus can be further
adapted and constructed to deliver a liquid to the fabric material. The portable cleaning
appliance can be adapted and constructed for removing creases or wrinkles from the
fabric material.
[0057] The portable cleaning appliance can include a heat source in thermal communication
with the work surface wherein the appliance transfers thermal energy to the fabric
material via conduction. The portable cleaning appliance can comprise a sole plate
for ironing the fabric material for the removal of creases or wrinkles from the fabric
material. A portable cleaning appliance can be adapted and constructed to prevent
emanation of the optical energy from the aperture for cleaning unless the sole plate
is positioned so as to be substantially horizontal. A portable cleaning appliance
can be adapted and constructed to apply a vacuum to the fabric material. A portable
cleaning appliance can be adapted and constructed to function as a vacuum cleaner
for removing particular matter from the fabric material using airflow.
[0058] The portable cleaning appliance includes the source of optical energy. The source
of optical energy can be disposed within the appliance body. The source of optical
energy can comprise a first source of optical energy that is separate from the appliance
body, and the portable cleaning appliance can include a length of optical fiber in
optical communication with the first optical source for delivering optical energy
from the first source of optical energy to the appliance body. The first source of
optical energy can comprise the source of optical energy. The first source of optical
energy can comprise an optical pump source for optically pumping the source of optical
energy. The source of optical energy can be integral with the appliance body. The
source of optical energy can comprise an optical amplifier for amplifying the optical
energy.
[0059] In further aspects of the invention, the fabric material comprises a practical fabric
material. The fabric material can comprise an article of clothing. The fabric material
can comprise upholstery. The fabric material can comprise a rug. The selected contaminant
can comprise an organic material. The selected contaminant can comprise an inorganic
material. The portable cleaning appliance can be of a size and weight such that it
can be readily spatially oriented in any direction with a single hand.
[0060] In other aspects of the invention, an optical parameter or characteristic of the
optical energy selected for cleaning can comprise a first wavelength of the optical
energy, where the first wavelength is in the range of about 200nm to about 750nm.
An optical parameter of the optical energy selected for contaminant removal can comprise
a selected wavelength of the optical energy, where the selected wavelength is in the
range of about 750nm to about 2,500nm. An optical parameter or characteristic selected
for contaminant removal can comprise a first selected wavelength of the optical energy,
where the first selected wavelength is in the range of about 2,500nm to 10,000nm.
[0061] In more aspects of the invention, an optical parameter or optical characteristic
of the optical energy selected for cleaning can comprise the temporal characteristics
of the optical energy. The optical energy can be emanated as substantially continuous
wave (CW) optical energy. The optical energy can be emanated as repetitive bursts
of CW optical energy or as CW optical energy emanated responsive to the user of the
portable cleaning appliance. The optical energy can comprise pulses having a time
duration of less than 1 picosecond. The optical energy can comprise pulses having
a time duration of less than 100 picoseconds. The optical energy can comprise pulses
having a time duration of less than 1 nanosecond. The optical energy can comprise
pulses having a time duration of less than 10 nanoseconds. The optical energy can
comprise pulses having a time duration of less than 100 nanoseconds.
[0062] An optical parameter or characteristic of the optical energy selected for cleaning
can comprise pulsing the optical energy to provide pulses having a pulse energy of
more than 10 nanoJoules. An optical parameter of the optical energy selected for contaminant
removal can comprise pulsing the optical energy to provide pulses having a pulse energy
of more than 1 microJoule. An optical parameter of the optical energy selected for
contaminant removal can comprise pulsing the optical energy to provide pulses having
a pulse energy of more than 10 microJoules. An optical parameter or characteristic
of the optical energy selected for contaminant cleaning can comprise pulsing the optical
energy to provide pulses having a pulse energy of more than 100 microJoules. An optical
parameter of the optical energy selected for contaminant removal can comprise pulsing
the optical energy to provide pulses having a pulse energy of more than 1 milliJoule.
[0063] A cleaning appliance, such as a portable cleaning apparatus (or any cleaning apparatus,
such as a convention washing machine) can be adapted and constructed such that one
or more of the cleaning parameters (e.g., optical parameters in the case of cleaning
appliance using optical energy) are selectable and changeable by the user of the cleaning
appliance. However, such selection and change can also be an automated process making
use of a built-in processor whose software or firmware can be upgraded over time to
optimise the performance of the appliance based on new information, new understanding,
development of new materials, dyes, stains and cleaning and stain removal detergents.
[0064] The invention has many aspects, including methods noted above. Some other methods
are now described in more detail.
[0065] In one aspect, a method of cleaning a material can comprise applying optical energy
to fabric material, the optical energy having one or more optical parameters selected
so as to clean a selected contaminant from the fabric material; and removing creases
or wrinkles from the fabric material and/or assisting in the cleaning of the material.
Removing the creases or wrinkles can comprise applying one or more of the following
to the fabric material: a vapour; a liquid; mechanical pressure; or thermal energy
to heat the fabric material. Aiding in the cleaning of the fabric material can comprise
applying one or more of following to the fabric material: a vapour; a liquid; mechanical
pressure; or thermal energy.
[0066] Alternatively, removal of wrinkles or creases can be attained without additional
thermal energy, whereby the presence of moisture in conjunction with local heat due
to absorption of optical energy results in the creation of steam within the fabric.
A heavy sole plate typical in most steam irons will then assist in the removal of
the wrinkles and /or creases. This has the added benefit in reducing the electrical
energy required for ironing clothing or textile items, removing the need for an inefficient
electrical heating system to generate steam and heat the sole plate of the steam iron.
A simple iron, could in effect become an iron that uses optical energy to heat the
liquid applied to the substrate and/or the substrate itself, such as for removing
wrinkles, independent of any process of cleaning using optical energy.
[0067] Regarding removing wrinkles or creases or aiding in cleaning, in various aspects
of the invention any of the vapour, liquid, mechanical pressure or thermal energy
can be applied alone or in any combination (e.g., vapour alone, liquid alone, mechanical
pressure alone, or thermal energy alone; vapour and liquid; vapour and mechanical
pressure; vapour and thermal energy; liquid and mechanical pressure; liquid and thermal
energy; mechanical pressure and thermal energy; vapour, liquid and mechanical pressure;
vapour, liquid and thermal energy; vapour, mechanical pressure and thermal energy;
liquid, mechanical pressure and thermal energy; vapour, liquid, mechanical pressure,
and thermal energy).
[0068] Regarding any of the foregoing, the application can be made in any order as part
of the cleaning or wrinkle/crease removing process, including simultaneously with
each other or with an application of the optical energy for cleaning or with an application
being made before or after others or before or after an application of optical energy
for cleaning.
[0069] Typically the thermal energy is applied via conduction, such as from a heated work
surface in physical contact with the fabric material. The work surface can apply the
mechanical pressure. However, radiation and convection are also within the scope of
the invention. Thermal energy can be applied to the substrate via application of optical
energy from the optical energy source, such as a laser source, alone in combination
with other sources of thermal energy. The source of optical energy can facilitate
removing wrinkles or creases. The optical energy can heat and/or vaporize a liquid,
such as water, delivered to the substrate. The optical energy can be used to create
steam.
[0070] In one aspect of the invention, removing creases or wrinkles from the fabric material
and/or assisting in the cleaning of the material comprises removing creases or wrinkles.
In another, removing creases or wrinkles from the fabric material and/or assisting
in the cleaning of the material comprises assisting in the cleaning of the fabric
material.
[0071] In additional aspects of the invention, applying one or more of a vapour; a liquid;
mechanical pressure; or thermal energy to heat the fabric material comprises applying
the vapour to the fabric material. The vapour can comprise steam. Applying one or
more of a vapour; a liquid; mechanical pressure; or thermal energy to heat the fabric
material can comprise applying the liquid to the fabric material. The liquid can comprise
water. The liquid can comprise a cleaning agent, such as a detergent.
[0072] In yet further aspects, other than ambient atmospheric pressure can be applied to
the fabric material, such as less than ambient atmospheric pressure or more than ambient
atmospheric pressure to the fabric material. The method can be practiced "blind",
that is, wherein the area being cleaned with the optical energy is not visible to
the user while the optical energy is being applied to the area. The method can comprise
slidingly contacting the fabric with a surface during the cleaning of the fabric material.
The optical energy can be applied to the fabric material as a beam and the surface
can substantially surround the beam.
[0073] The method can comprise ironing the fabric material and the application of any of
the vapour, liquid, mechanical pressure or thermal energy can be part of the ironing
process.
[0074] First and second are used herein as identifiers; the use of "first" does not necessarily
mean there must be a "second", nor does the use of "second" mean there must be a "first".
[0075] Optical energy can be characterized by a number of optical parameters, and the portable
cleaning apparatus can be adapted and constructed to provide optical energy having
one or more of the parameters selected to clean a particular contaminant from a particular
fabric material. Certain examples are given above. By way of further example and not
limitation, useful optical parameters can include the spatial intensity profile or
distribution of the optical energy (e.g., Gaussian, substantially flat topped, fluence,
or other feature related to the a spatial intensity profile or distribution); spectral
makeup (wavelength or wavelengths); the relative intensities of the spectral components;
spectral bandwidth and any spectral chirp (the foregoing can typically be ascertained
by spectral intensity profile of the optical energy); average power; temporal intensity
profile (e.g., CW, pulsed, quasi CW, particular pulse train, or other type of temporal
profile). Where the optical energy is pulsed, the parameters can include pulse energy,
peak power, pulse duration, pulse shape (e.g., shape of the temporal intensity profile),
repetition rate, duty cycle, as well as pulse train characteristics (e.g., a pulse
train of pulses having different optical parameters). The location of an image plane
relative to the surface of the fabric material (e.g., above the surface, substantially
at the surface, or below the surface) is yet another example of an optical parameter
that can be selected.
[0076] Unless otherwise defined, time durations, such as pulsewidths, and bandwidths as
specified herein are full width, half maximum (FWHM) time durations and bandwidths.
[0077] "Laser", as that term is used herein, can include a structure (e.g., a fiber laser)
having a resonant cavity, a master oscillator power amplifier (MOPA) arrangement (e.g.,
diode oscillator with a fiber or bulk optic amplifier); a diode laser; an ASE source;
or a supercontinuum source. A source of optical energy as referred to herein need
not comprise a laser - a high power lamp may be suitable in certain practices of the
invention, most likely with appropriate filtering to select desired wavelengths. A
laser, however, is typically preferred, as lasers can more readily provide optical
energy confined to a small space and therefore ensure a high optical intensity at
the substrate (e.g., fabric material) for improved efficiency of the cleaning process.
A cleaning appliance as disclosed above, such as a cleaning appliance, can be adapted
and constructed to be portable and/or hand held.
[0078] "Fabric material" is typically (but need not be) a woven, knitted or felted material,
and can include a textile. A fabric material may comprise textile fibers, such as,
for example, one or more of (alone or in any combination) man-made fibers such as
nylon, cellulose acetate, polyester and or naturally occurring fibers such as cotton
and wool. A fabric material may be primarily for practical use. Such a fabric material
is referred to herein as "practical fabric material" and includes, for example, articles
such as clothing, rugs, upholstery, bed sheets, towels, wash cloths, table cloths,
handkerchiefs, shower curtains , window drapes, pillow covers, and quilts, which are
just some examples. As used herein the term "practical fabric material" is intended
to exclude works of art intended substantially only for viewing (e.g., exclude the
painted canvas of a framed picture).
[0079] A fabric material may be for sustained human contact, where sustained means not transient
or unexpected or unusual, but typically expected and anticipated as usual by the designer
or creator of the fabric. However, sustained human contact need not necessarily be
continuous or by the same person, and not necessarily direct skin contact. For example,
a rug is an example of a fabric that would receive sustained human contact, but typically
by many different people and typically via their footwear. The painted canvas would
typically not undergo sustained human contact. Most or many practical fabric material
would undergo sustained human contact. Fabric materials can be conforming fabric materials
- that is, they can comprise a flexible material that readily conforms to an object
they are draped over or that is manufactured to conform to a subject or object (e.g.,
a shirt or a car cover).
[0080] "Blind as to the user" means that the when the portable cleaning appliance is in
use to clean a workpiece, the area being cleaned by the optical energy is not under
normal and anticipated use directly visible to the user of the appliance. "Directly
visible" does not include video camera/screen arrangements (such are used in optical
splicers, for example). Such arrangements do not provide for direct vision. The wearing
of laser goggles to view a cleaning process does, as the term is used herein, mean
the process is directly visible. "Appliance" is used interchangeably with "apparatus"
herein. "Within the appliance body" refers to the volume within the overall outermost
surface of the appliance.
[0081] "Oriented substantially horizontally" means that the central axis of a beam of optical
energy emanating from the portable cleaning appliance is substantially perpendicular
to the horizontal plane (which is taken as level), that is, with about 15 degrees
of the vertical axis that is perpendicular to the horizontal plane.
[0082] "Stray optical energy", as that term is used herein, refers to optical energy that
propagates such that it can be incident on something other than the subject of the
cleaning process (e.g., the fabric material), such as the user of the portable laser
appliance, or a bystander. Stray optical energy is undesirable and can be created
even when the portable laser cleaner is orientated such that the optical energy is
directed at the fabric material. Creation of stray optical energy can involve one
or more of a number of processes, such as scattering, reflection, refraction, or diffraction.
In a perfect cleaning process (from the perspective of safety) no optical energy would
emanate from the laser appliance except directly at the workpiece, and that optical
energy would do its cleaning job without creating any stray optical energy, so that
no optical energy could be incident on the user or a bystander.
[0083] Several aspects of the invention are described above, in varying detail as to the
features of each of the aspects. Any of the features of one of the aspects can be
included as an additional or alternative feature of any of the other aspects, practices
or embodiments of the disclosure described herein, except where clearly mutually exclusive
with another feature of an aspect, practice or embodiment or where a statement is
explicitly made herein that certain features will not work in such a combination.
To avoid undue repetition and length of the disclosure, every possible combination
is not explicitly recited. Furthermore, as the skilled worker can ascertain, a method
of the present disclosure can comprise the steps relating to the function or operation
of the features of apparatus and systems disclosed herein.
Brief Description of the Drawings
[0084]
FIGURE 1 schematically illustrates an apparatus for cleaning a substrate using optical
energy from a laser whereby the beam and/or the substrate can be translated;
FIGURE 2 schematically illustrates a configuration for beam shaping, suitable for
use with any of the apparatus described or shown in the other FIGURES herein (except
where clearly incompatible), whereby the beam is made into a large spot either through
collimation or by diverging the beam. The large spot can provide a "flood" illumination
covering a larger area of the substrate, spreading out the optical energy over a larger
area;
FIGURE 3 schematically illustrates a configuration 40 for beam shaping, suitable for
use with any of the apparatus described or shown in the other FIGURES herein (except
where clearly incompatible), wherein the optical beam is shaped into a thin stripe,
allowing a large area coverage in one axis, yet maintaining a high intensity of the
optical field in an orthogonal axis;
FIGURE 4 illustrates a line-illumination system, suitable for use with any of the
apparatus described or shown in the other FIGURES herein (except where clearly incompatible),
with additional features to enhance the contaminant cleaning process, including modulation
to enable pulsing or gating of the optical beam, wavelength filtration (in the case
of a broadband or multi-wavelength light source) to optimise the optical wavelength
for the specific contaminant or substrate, variable attenuator or power control of
the light source output to control the rate of material removal or fluency of light
at the substrate surface;
FIGURE 5 schematically illustrates an apparatus including a rotating-drum concept
similar to a conventional drum washing machine;
FIGURE 6 schematically illustrates an apparatus including a "mangle-type" of design,
whereby the substrate passes through the optical beam as a flat substrate;
FIGURE 7 schematically illustrates an apparatus wherein a beam of optical radiation
is delivered to the substrate by a movable enclosure and where the source of optical
energy is external to the enclosure with the optical energy delivered between the
source and enclosure via an optical light guide;
FIGURE 8 schematically illustrates an apparatus wherein a beam of optical energy can
be delivered to the substrate by a movable enclosure and where the optical source
is mounted within the enclosure;
FIGURE 9 illustrates the apparatus of FIGURE 8, with further illustration of safety
features to prevent accidental exposure of the optical beam to the user or to prevent
extensive exposure of the optical energy to the substrate which might otherwise cause
damage to the substrate. Safety features can include a position sensor for interlocking
the laser to only allow operation of the source of optical energy where there is no
possible exposure to the user's skin and/or eyes. Safety features can also or alternatively
include a motion sensor which determines if the optical beam is moving with respect
to the substrate or at what speed this motion exists;
FIGURE 10 schematically illustrates an apparatus in the form of a Light (or Laser)
Iron (LIRON™);
FIGURE 11 schematically Illustrates a LIRON 120, with the source of optical energy
121 mounted external to the LIRON body and the beam being delivered to the hand held
LlRON via optical cable 125. The beam in this example is shown as a focussed spot
which can be fast-scanned horizontally over the width of the LIRON base or sole plate;
FIGURE 12 schematically illustrates another LIRON apparatus, similar to that of FIGURE
11, where the LIRON is adapted and constructed for providing steam, water, or air
to the substrate exposed to the optical energy. Delivery of steam, air, etc., can
assist in the removal of the contaminant from the substrate, and can be simultaneous
with, or before or after, an application of cleaning optical radiation to the substrate;
FIGURE 13 schematically illustrates yet another LIRON apparatus where the LIRON includes
a suction pump or vacuum to assist in the removal of contaminant from the substrate
and the suction or vacuum pump may be integral with the LlRON apparatus;
FIGURE 14 schematically illustrates another LlRON apparatus, in this instance including
an external suction pump or vacuum to assist in the removal of contaminant from the
substrate and optional microprocessor and data port;
FIGURE 15 schematically illustrates another LIRON apparatus 161 where the LIRON is
provided with a dedicated LIRON Board 162 similar to an ironing board onto which the
substrate 165 (e.g., fabric material) can be positioned during the ironing process.
The board can include a suction or vacuum pump 166 and perforated substrate mounting
surface such that suction can be provided to the substrate to assist in removal of
contaminants from the surface as well as aid in maintaining the substrate in place
on the board;
FIGURE 16 illustrates an example of a method of cleaning a substrate comprising a
fabric material (depicted in FIGURE 18 as an item of clothing) according to an embodiment
of the invention, which can be practiced, for example, using the apparatus shown in
FIGURES 11-15;
FIGURE 17 illustrates another embodiment of a method of cleaning a substrate comprising
a fabric material, (depicted in FIGURE 19 as an item of furniture) according to an
embodiment of the invention, which can be practiced, for example, using the apparatus
shown in FIGURES 11-16;
FIGURE 18 illustrates an apparatus including a "flatbed" design and an integral source
of optical energy and a scanner unit which translates a beam through a transparent
window to the surface of the substrate mounted on top of the transparent window. The
apparatus can include a hinged lid that provides a light-tight seal whilst also helping
to maintain the substrate in flat contact with the transparent window;
FIGURE 19 illustrates an apparatus wherein the substrate to be cleaned can be mounted
vertically or horizontally, and the beam from the source of optical radiation can
be scanned across the surface of the substrate through translation of the laser beam
and /or optical source. The apparatus of FIGURE 19 can be useful for industrial cleaning
systems whereby large-area, flat substrates, such as sheets of material, are to be
cleaned;
FIGURE 20 shows an example of a cotton fabric having been contaminated with a dark
oil from an engineering workshop and subsequently cleaned using a pulsed laser beam;
FIGURES 21a and 21b illustrate the laser cleaning of a food stain from a cotton shirt;
FIGURE 22 shows examples of the laser cleaning of samples of cotton material, contaminated
with different food stains such as tea, curry and oil, red wine, and grass.
Detailed Description
[0085] FIGURE 1 illustrates an apparatus 10 for cleaning of a substrate, such as, for example,
a practical fabric material. The apparatus 10 comprises an optical transmission pathway
arranged for propagating optical energy received from a source of optical radiation
for emanation of the optical energy for the cleaning of the substrate, and which in
the apparatus of FIGURE 1 can comprise a beam expander, focussing lens and scanning
head. For example, the optical output beam 11 from the source of optical energy, which
preferably comprises laser source 12, is beam shaped using a beam expander 13 and
focussing lens 14 into a focussed beam 15 at the surface of a substrate 16. The beam
can be scanned over the substrate surface using a laser beam scan head 17 and the
substrate can be scanned with respect to the focussed beam using an x-y or x-y-z axes
translation stage 18. Typically the laser, scan head and translation stage are controlled
by a computer 19 (a processor could be used as well, without one or more of the typical
features of a computer) to determine the location, timing, and power level at which
the laser radiation is delivered to the substrate. The beam 15 can be focussed to
a small spot to enhance the optical intensity of the beam at the substrate surface
and scanned for cleaning a selected area of the surface of the substrate. In one example
considered to effect cleaning of a fabric material, the laser source can comprise
a pulsed fiber laser delivering short pulses of approximately 20 nanoseconds in duration
at an average power of 20W and pulse energy of up to 800 µJ at a wavelength of 1064
nm. The fabric material can be dampened with water to aid the cleaning process. In
another example considered to effect cleaning of a fabric material, the laser source
can comprise a pulsed diode pumped solid state laser delivering pulses of below 200
nanoseconds at a wavelength in the visible region of the spectrum.
[0086] FIGURE 2 illustrates an apparatus 20 comprising an optical transmission pathway wherein
the beam from a laser source 21 is shaped by beam shaping optics 22 into a larger
beam or divergent beam 23 which becomes a large spot when incident on the substrate
24. Such illumination is often referred to as flood illumination, and the apparatus
10 can alternatively use such flood illumination in place of a focussed beam 15.
[0087] FIGURE 3 illustrates another apparatus which depicts an optical transmission pathway
that involves the shaping of a laser beam 31 by beam shaping optics 32 in the form
of a cylindrical lens into an elliptical beam with a very high degree of ellipticity
such that the shaped beam 33 takes the form approximating a thin stripe of light when
incident on the substrate 34. Such an illumination is often referred to as line illumination,
and such line illumination can alternatively be used in apparatus 10 in place of the
focussed beam 15.
[0088] FIGURE 4 illustrates the apparatus of FIGURE 3 where the optical transmission pathway
includes additional feature(s) 41 enabling one or more additional controls of the
source of optical energy (i.e., the laser) including modulation of the laser in time
and power, and wavelength filtration of the laser (when integrated as a broadband
or multi-line laser source) to deliver the optimum wavelength for efficient processing
of different material substrates. The apparatus shown in FIGURE 1 can be modified
according to FIGURE 4, and the apparatus of FIGURE 1 so configured used to clean a
fabric material. Any of the apparatus discussed above or below, such as in conjunction
with the FIGURES, can include one or more additional feature(s) 41 for conditioning
the optical energy or beam, where the additional feature(s) can include one or more
of an attenuator, modulator, filter, etc., and one or all of such feature(s) 41, and
one or more of the beam expander 13 or translation stage 18 or scan mechanism can
also be included in other apparatus shown or described herein, as well as controlled
by a processor described above and below, where the processor can be configured for
controlling the cleaning process responsive to programming and/or data (information)
communicated to the processor from a user data interface. The data can be read, for
example, from a data element associated with (e.g., integrated with) a substrate,
as is described in more detail herein.
[0089] FIGURE 5 illustrates a cleaning apparatus 60 based around a rotating-drum arrangement.
Here the optical transmission includes a spinning mirror. An optical beam 61 is delivered
by a source of optical energy 62 along the central longitudinal axis of a drum 63
which rotates around the longitudinal axis. The substrate to be cleaned 64 can be
positioned flat on the internal surface of the rotating drum. This positioning can
be attained through mechanical fixings or a suction mechanism within the drum (not
shown in this FIGURE). Preferably the positioning of the substrate on the drum internal
wall is attained through centrifugal forces as the drum rotates at high speed.
[0090] The spinning, scanning mirror 65 is mounted on a spindle 66 located on the central
longitudinal axis of the rotating drum. The optical beam is incident on the mirror
which deflects the beam to be incident at the surface of the fabric material substrate
on the internal drum wall. The rotation of the drum, spinning of the mirror and longitudinal
translation of this mirror along the spindle over time results in the optical beam
scanning the entire internal surface area of the rotating drum, attaining a complete
coverage of the substrate within the drum, and cleaning the entire substrate. Repeat
scans of the substrate surface can be attained by continual rotation of the drum,
continual spinning of the mirror and continual translation of the mirror along the
central spindle of the drum.
[0091] Further assistance to the cleaning process, as with all embodiments of the invention
described herein, can include the provision of suction to clean contaminants from
the drum and/or substrate, application of assistance mechanism; water, solvents, detergents,
stain removers, oxygen-based bleaching agent, steam, compressed gas etc. to substrate
or drum or locally as a nozzle, focussing the assistant mechanism to the incidence
region of the optical beam.
[0092] The source of optical energy preferably comprises a laser. The laser can be selected
on the basis of performance and cost and can be selected from a wide variety of laser
types including, but not limited to, semiconductor diode lasers, fiber lasers, diode-pumped
solid state lasers, gas lasers and combinations thereof. The laser source can deliver
the laser light as continuous wave (CW), gated CW, pulsed or as bursts of pulses,
said pulses being in the sub-picosecond, tens of picoseconds, sub-nanoseconds or greater
than 1 nanosecond pulsed duration. The laser can deliver light in the infra red, near
infra red, visible or UV region of the spectrum or can cover multiple regions of the
spectrum as a continuous spectral band or a series of discrete wavelengths or wavelength
bands. The laser, if of broadband spectral coverage, can include additional filtration
to provide wavelength selection optimised to the contaminant and or substrate. These
considerations can apply to all embodiments taught herein.
[0093] FIGURE 6 illustrates an apparatus 70 designed for the cleaning of a substrate comprising
contaminated fabric material. The optical transmission pathway includes a mangle type
structure. The contaminated fabric to be cleaned 71 is passed through a mangle 72
which is adapted to pass one or more optical beams 73 from an optical source 74 and
direct them onto one or more of the substrate surfaces as the substrate is passed
and forced flat, translating through the mangle space in the mangle.
[0094] As described in conjunction with FIGURE 5, the beam can be focussed to a small spot
or shaped into a large spot on the substrate as a collimated or divergent beam. Alternatively,
the beam can be shaped into a stripe at the surface of the substrate. The beam can
be fixed in position or alternatively scanned by a beam scanner.
[0095] FIGURE 7 shows a cleaning apparatus for cleaning a substrate, such as a substrate
comprising a fabric material, according to the present invention. The cleaning apparatus
is configured as a module or body 80 which can be moved with respect to the substrate,
the module delivering the optical beam 81 to the substrate surface 82 preferably via
aperture 83, which can comprise an optical window that is transmissive at the wavelength
of the source of optical energy. The source of optical energy is located external
to the module 80 and optical energy from the optical source is delivered to the module
by a light guide such as an optical fiber or light guide of the optical transmission
pathway. The module can comprise the beam shaping optics 89 and beam steering optics
88 of the optical transmission pathway to focus or shape the beam to the desired parameters
at the substrate surface. The beam shaping optics may produce a focussed beam, or
line or broad area beam at the substrate surface. The beam steering optics may additionally
comprise a scanning mirror 86 to scan the beam across the substrate surface such as
to provide broad area scanned coverage of the substrate surface and/or to prevent
over exposure of a particular region of the substrate and the local build-up of heat
due to locally-absorbed optical energy. The apparatus may include the one or more
additional feature(s) 41, such as shown in FIGURE 4.
[0096] The module preferably also includes a mechanism for controlling (automated or manually
through user adjustment) various parameters of the optical beam including, but not
limited to, power, pulse duration, wavelength, pulse repetition rate and beam size.
One example of such a mechanism is user input 87 such as a knob or keypad.
[0097] The module can be moved around the substrate to produce wide-area coverage and cleaning
of large regions of the contaminated substrate. The module can be moved by hand via
a mounted handle 84 or could be mounted on a gantry or robot for more industrial,
automated cleaning applications, for example in large pieces of professional cleaning
equipment or within environments such as nuclear and chemical sites, where it is not
possible for people to be present. The bottom of the module can comprise a work surface
for contacting (e.g., slidingly contacting) the substrate as the module is moved around
during the cleaning process. The work surface can surround the aperture, as shown
in FIGURE 7.
[0098] FIGURE 8 illustrates another a cleaning apparatus for cleaning a substrate with the
same features and variations as FIGURE 7 with the difference that the optical source
91 is located within the module 90.
[0099] FIGURE 9 illustrates another a cleaning apparatus for cleaning a substrate with the
same features as FIGURES 7 or 8 but with additional safety interlock features specifically
shown by way of example (which features may apply as well to the apparatus of FIGURE
8). The optical source can be a laser source and the laser source can comprise a class
4 laser source requiring strict laser safety controls and appropriate interlocks.
In order to utilise such a class 4 laser apparatus within a domestic environment,
and in many industrial environments, the system should be failsafe to ensure that
the user cannot be exposed to the laser beam beyond those acceptable exposure limits
as governed by applicable laser safety standards. FIGURE 9 gives an example of how
this cleaning apparatus might be implemented as a safe-to-use commercial appliance.
[0100] Referring to FIGURE 9, one or more sensors 100 on the bottom of the module or body
104 can be position sensors to sense whether or not the module is flat against a surface,
thereby preventing access to the light aperture of the module and exposure of the
end user's skin or eyes to potentially harmful levels of optical radiation. The sensors
100 can also or alternatively be motion sensors to detect if the module or body is
moving relative to the substrate and also optionally detect the speed of this movement.
The motion detector can control the delivery of the optical energy to the substrate
from the optical source in the event of low or no movement to control the dosage delivered
to the substrate or to prevent the lengthy exposure of the substrate to the optical
energy which might otherwise damage or degrade the substrate material. The motion
detector can also or alternatively control the fluence of the optical energy onto
the substrate dependent on the speed of translation of the body to achieve a consistent
or optimised or limited exposure of the substrate to the optical energy. The sensors
can be electrical, optical, magnetic, pressure or any other type of sensor. Furthermore,
to make the system failsafe, the module could be designed to only work on a given
platform. For example, in an industrial machine, the base plate 101 on which the substrate
102 is mounted may be fabricated from a specific material or emit a specific frequency
or optical wavelength that the position sensors 100 must detect in order for the source
of optical energy 103 to operate. Typically, the laser source within a commercial
system would have at least one interlock and preferably two interlocks, requiring,
for example, all position sensors to detect that the module is flat against a surface
and that the system is light-tight, not allowing scattered optical radiation to exit
from the module leading to potential user exposure. Only when position sensors are
in place can the laser operate. In the apparatus shown by FIGURE 9, the light source
103 is located external to the module 104. In this case, additional protection would
be required to detect a break in the optical delivery cable 105 with implementation
of an interlock to shut down the optical source in the event of an output power failure
due to optical cable break. The source of optical energy can be included with the
appliance body, rather than external to the body.
[0101] It will be appreciated that the apparatus shown in FIGURES 1- 9 can implement other
mechanisms to assist (the optical source) with the cleaning process. Such additional
mechanisms can include, for example, the use of water to dampen the contaminated substrate,
steam to provide heat, moisture and pressure to the cleaning process, vacuum or compressed
air to provide removal of any removed contaminant particles through suction or by
blowing the contaminant away from the substrate, chemicals including detergents, stain
removers, oxygen-based bleaching agents, or anti-oxidants which provide a chemical
reaction to assist the removal of the contaminant from the fibers of the substrate
textile. When assisting the cleaning process using a chemical such as a detergent,
the detergent can comprise surfactants, enzymes, oxygen-based bleaching agents, builders,
optical brighteners and other ingredients of commercial detergents. The detergent
can contain less than 5% of the oxygen-based bleaching agent. The detergent can contain
more than 5% of the oxygen-based bleaching agent. The detergent can contain more than
15% of the oxygen-based bleaching agent. The detergent can contain more than 30% of
the oxygen-based bleaching agent. The percentages can be by weight. When including
a chemical to assist in the cleaning process, the optical energy from the optical
source can provide localised heat which increases the effectiveness of the chemicals
such as detergent, enzyme and bleaching agent. The optical energy can also increase
the mobility of the contaminant molecules making them easier to react with the chemical
and clean from the substrate.
[0102] The modules shown in FIGURES 7-9 represent a cleaning tool for substrates, and in
particular substrates comprising a fabric material, which can be hand held or mounted
on an automated mount such as a gantry or robot.
[0103] FIGURES 10 - 15 show hand-held modules, such as those described above in FIGURES
7 - 9, with the modification that the modules are now further configured as an iron,
such as a steam iron for use, for example, in the domestic and commercial ironing
of fabric materials. The "Light Iron" is hereby referred to as a LIRON for the purposes
of this invention. FIGURES 10 -15 show examples of how the cleaning apparatus can
be combined with other mechanisms which assist with the cleaning process. FIGURES
10 - 15 further show how the laser cleaning apparatus can be designed to be combined
with other functions such as crease or wrinkle removal, typically attained with a
conventional iron, steam iron or steam generator iron. One or more of the features
shown in FIGURES 10 -15 can be included, alone or in any combination, in the apparatus
shown in FIGURES 7- 9.
[0104] A traditional iron or steam iron or more recently steam generator iron, is used to
remove creases from fabric materials, most commonly clothing and household textiles
including bed sheets, table cloths etc. Most commonly, the iron is in the form of
a steam iron, including not only heat but also a water sprayer and source of steam
to help with the ironing process. The steam iron uses superheated water to eliminate
wrinkles in clothes and fabrics which may not be suitable for traditional dry ironing.
Distilled water is usually poured into a holding tank and special heating elements
convert it to steam. This hot mist comes out through a number of holes in the soleplate
or bottom plate, which typically is heated by a source of thermal energy (e.g., an
electric heating element) of the steam iron. As the steam loosens the individual fibers
of the clothes, the steam iron's pressing action smooths out wrinkles or creases.
[0105] Ironing is a process carried out typically after washing and drying fabric materials.
It is an additional task in the home and is required in most cases to remove creases
and wrinkles, though some "non-iron" fabrics are available where limited ironing is
required.
[0106] FIGURES 10-15 show examples of a hand-held cleaning tool for fabrics (substantially
similar to those shown in FIGURES 7-9, with the differences now shown or described).
However, the apparatus described in FIGURES 10 - 15 also have the option to provide
or enhance the function of crease or wrinkle removal in addition to the cleaning capability.
In many cases, an item of clothing or a table cloth, bed sheet, etc. might have very
light soiling yet is cleaned on a regular basis. An example is a shirt worn by a typical
office worker. This shirt may be worn once per day, after which it is cleaned in a
conventional washing machine and then ironed to remove the creases. In actual fact,
the shirt will have very minor amounts of dirt around the collar and cuffs, perhaps
a localised food stain and regions of odour from the wearer's body. The abrasive washing
nature of a conventional drum-machine is not required to clean this item of clothing,
yet this is the only solution. The hand-held cleaning system shown in FIGURES 7-9
and the LIRON system shown in FIGURES 10 -15 provides a tool to clean such items of
clothing, to remove dirt, odours and stains and, if necessary, to achieve this process
whilst simultaneously removing the creases from the textile (item of clothing).
[0107] FIGURE 10 shows an example of a hand-held light cleaning apparatus implemented as
an iron. The LIRON 110 can comprise one or more of all the features of a traditional
steam iron, including, but not limited to a body, a heat generator and heat control
via thermostat and user control 118, steam generator and water reservoir 111, water
sprayer, holes in the base 112 to allow steam to be directed onto the substrate textile,
power cable 113 etc. The bottom surface of the base can be a work surface, such as
work surface for slidingly contacting the fabric material during the cleaning thereof.
In addition, the LIRON contains a source of optical radiation 114 and an optical transmission
pathway between the source of optical energy and an aperture for emanating the optical
energy for cleaning the substrate. The optical transmission pathway can comprise beam
steering optics, 115, beam shaping optics 116 for conditioning and/or propagating
the optical energy to aperture, which can include a transmissive optical window. In
this specific example, the beam shaping optics form the output of the source of optical
energy into a narrow stripe covering the width of the optical window of the base of
the apparatus. This apparatus would typically include power control of the light source
as well as control of other features including the pulse duration or duration of optical
bursts provided to the substrate, the duty cycle of these bursts and other parameters
of the optical output which can help optimise the process of removing contaminants
from the substrate textile. Such controls would preferably be available with easy
access to the user of the apparatus. The apparatus of FIGURE 10 can include one or
more of the additional elements 41.
[0108] One possible implementation is shown in FIGURE 10 as a knob (or touchpad) 118 on
the LIRON. The specific control settings may be dependent on the type of fabric material
and can be pre-set and calibrated such that the user simply sets the apparatus operating
parameters dependent on the textile type (cotton, wool, synthetic etc) and / or contaminant
type (stain, blood, wine, oil, grease etc). Alternatively, the control settings can
be set and altered by a microprocessor on board or external but connected to the apparatus
(for purposes of illustration, an internal processor is shown in FIGURE 14, and can
be included in FIGURE 10 as well). The control settings can be set for a given substrate
material, contaminant type, garment type or brand, detergent or chemical type or brand.
The settings can also be adjusted live throughout the cleaning process through feedback
of the speed of motion of the apparatus with respect to the substrate or even by measurement
of the amount of contaminant being cleaned from the substrate. The settings can be
pre-set for a range of garments, substrate types or detergent type or alternatively
the settings can be optimised for a given garment, brand of clothing, detergent, brand
of detergent and the settings uploaded onto the microprocessor by means of a suitable
communications means such as a USB, RS232, wireless port or via a scanner such as
a bar-code scanner.
[0109] The control settings can be upgraded, as described elsewhere. Also shown in FIGURE
10 are a series of sensors 119 which can be position sensors and/or motion sensors
and are used as a safety feature and/or a feature to prevent damage to the substrate
due to excessive optical exposure. The sensors are useful if the optical output of
the apparatus exceeds the legal limits for safe human exposure. Such position sensors
are linked to safety interlocks for the optical source and allow operation of the
source only when the apparatus is in a safe position whereby no light leakage and
optical exposure to the user is possible, as described in conjunction with FIGURE
9.
[0110] FIGURE 11 schematically illustrates another LIRON 120, substantially similar to FIGURE
10 except with the following differences. The optical source (otherwise referenced
to herein as source of optical energy) 121 is positioned external to the apparatus
body 125 with the optical transmission pathway comprising a flexible optical light
guide such as an optical fiber. Beam shaping optics 122 and beam steering optics 123
optimise the shape and position of the light beam at the output aperture on the base
of the apparatus. The beam is focussed to a small spot 124 at the aperture to optimise
the intensity of the beam at the substrate to be cleaned. The beam steering optics
include a scanner which scans the focussed beam from side to side along the light
aperture window shown (by way of example only) as a thin window in this example. The
scanning speed is preferably arranged to be fast such that the focussed spot does
not dwell for a long period at any one spot, potentially leading to heat build-up
locally in the substrate.
[0111] FIGURE 12 schematically illustrates another LIRON, which can be substantially similar
to FIGURE 11 with the differences now described The optical source 131 is also positioned
external to the apparatus 130 with the light delivered to the apparatus by a flexible
optical light guide 133 such as an optical fiber. It will be appreciated that the
optical source could be equally positioned within the apparatus, as shown in FIGURE
10. The apparatus is identical to the apparatus of FIGURE 11 with the addition that
there is provided a mechanism such as the opening of a nozzle 132 for directing steam
(this could also be water, air, gas, detergent, oxygen-based bleaching agent, stain
remover or other assistant mechanism or cleaning agent for the optical cleaning process)
locally at the substrate where the optical beam is incident at the substrate. The
locally focussed steam or gas can assist in the removal of contaminant from the textile
by providing thermal energy to the process or simply by applying a pressure to "blow-away"
contaminant particles removed from the textile fibers by the optical beam and any
assistant mechanism. The apparatus can include a reservoir in fluid communication
with the opening.
[0112] FIGURE 13 shows yet a further LIRON apparatus, again with the optical source 141
external to the apparatus 140 (and again the source of optical energy can be included
within the body, as shown in FIGURE 10). The apparatus of FIGURE 13 is identical to
that shown in FIGURE 12 with the addition of a vacuum or suction pump 142 within the
apparatus, such suction being directed by a nozzle 143 locally to the substrate in
the region where the optical beam cleans contaminants from the substrate. The suction
pump serves to extract debris or contaminants or cleaning agent, which can include
such contaminants, from the substrate, which are often removed or dislodged from the
textile fibers by the cleaning process, such as by the optical beam and any assistant
mechanism. In the case where a chemical assistant solution such as a detergent, stain
remover, oxygen-based bleaching agent, water or steam is applied to the substrate
via the opening of the nozzle 132, the vacuum or suction pump 142 extracts contaminated
chemical assistant solution via an orifice or opening, such as the orifice or opening
of the extraction nozzle 143, providing a continual flow of chemical assistant solution
across the substrate. The suction pump can be operated continually or repeatedly to
provide continual or repeated replenishment of the solution during the cleaning process.
It will be appreciated that the mechanism described in this apparatus to achieve flow
of a chemical assistant solution can be achieved in a number of different formats
and that the vacuum suction and delivery 132 and extraction 143 nozzles can be located
internal to the apparatus or external to the apparatus. Further, the mechanism to
achieve flow of chemical assistant solution can be incorporated with any other apparatus
described within the current disclosure. Although in FIGURE 13 a suction pump 142
and nozzle 143, as well as nozzle 132 are both shown, the apparatus need not include
the opening of the nozzle 132, a cleaning agent or other liquid or solution can be
delivered externally, such as by a hand held dispenser.
[0113] FIGURE 14 shows yet another LIRON apparatus, which can incorporate one or more of
the features of any of FIGURES 7 - 13, but again with the optical source 151 mounted
external to the LIRON apparatus 150 (it could be inside) and where the vacuum or suction
pump and/or the source of assistant mechanism (steam, gas, detergent, stain remover,
oxygen-based bleaching agent etc) 152 are also mounted external to the apparatus and
directed to the region of the optical beam, shown in FIGURE 14, by an opening or orifice,
such as an opening or orifice of the nozzle 153.
[0114] Also shown in FIGURE 14 is an optional processor 154 which can be configured to output
signals that control the cleaning of the substrate by the cleaning appliance. The
processor can control one or more parameters of the overall cleaning process including,
but not limited to, optical energy source 151 parameters, shaping optics 123 parameters,
feature(s) 41 sensors 119, or nozzles 143/153. The processor's controlling capabilities
can be updated and configured via an optional external user data interface 155 (i.e.,
USB, RS232), wireless communications (i.e., WiFi, Bluetooth), near-field communications
(i.e., RFID reader, barcode reader) or a user input interface such as a keypad or
touchpad 118.
[0115] A person of ordinary skill in the field of this invention, cognizant of the disclosure
herein, will appreciate that a microprocessor can be integrated into any of the apparatus
disclosed herein, such as (but not limited to) the apparatus shown in FIGURE 7-15,
to similarly control overall cleaning process parameters, including one or more of
optical parameters or characteristics defined in more detail elsewhere herein.
[0116] As one example, referring to FIGURE 9, a processor can receive signals from sensors
100 and, in response, alter optical characteristics of other cleaning process parameters,
singularly or in combination, via communication with one or more of beam steering
optics 88, beam shaping optics 89, scanning mirror 86, or optical energy source 103
parameters. Referring to FIGURE 13, a microprocessor can receive signals from sensors
119 and, in response, manipulate overall cleaning process parameters, singularly or
in combination, such as nozzle 132 dispense flow, suction pump 142 suction power,
and optical parameters as previously discussed.
[0117] In apparatus comprising a processor, the processor can also be coupled with a data
input source which allows the user to alter cleaning process parameters manually or
automatically. A memory means can also be coupled with the processor to store pre-programmed
cleaning recipes (i.e., sets of cleaning process parameters). Examples of manual alteration
include inputting parameters through a knob, keypad or touchpad. Automatic alteration
examples include importing data through a data port (i.e., USB, RS232), wireless communications
(i.e., WiFi, Bluetooth), or near-field communications (i.e., RFID reader, barcode
reader). Using one of these input means, the user can cause the microprocessor to
load pre-programmed cleaning process parameters based on, for example, fabric and/or
contaminant type. The user can also manually override select parameters directly through
a knob, keypad or touchpad.
[0118] FIGURE 15 shows a handheld cleaning device 161 which can be in the form of any of
the apparatus described. In addition to the handheld apparatus, there is provided
a specific base 162 which partners with the handheld or gantry mounted apparatus for
cleaning. The base can be simple like a conventional ironing board used in domestic
ironing processes. The base can contain other features which make up the entire cleaning
and/or ironing system. For example, the base can be designed to enable the position
sensors 163 and interlock system by containing part of the sensing system such that
the apparatus optical source 164 can only operate when the apparatus is in position
on the specific base. The position sensor could, for example, comprise an optical
or electrical transmitter-detector pair, with one of the transmitter and detector
being positioned within the base whilst the other remains with the hand-held cleaning
apparatus. The base 162 could include sensors for sensing the proximity of the cleaning
appliance, for purposes of providing an interlock. The sensors of the base can be
in communication with the processor, which controls the operation of the optical source
of conditioning element(s) 41 (e.g., a beam stop) in the appropriate optical path.
[0119] The base 162 of FIGURE 15 can further comprise a suction pump which serves to remove
debris from the textile having been cleaned by the hand held cleaning apparatus. The
suction pump also can provide a means for ensuring that the textile substrate 165
is flat against the top surface of the base.
[0120] FIGURES 16 and 17 show example uses of a hand-held cleaning and hand-held cleaning
/ ironing (LIRON) apparatus in the cleaning of fabric materials. The LIRON 110 of
FIGURE 10 is shown here but it will be appreciated that any of the apparatus of FIGURES
7-15 may be used in this way. FIGURE 16 uses the case example of a clothing garment
171, whilst FIGURE 17 uses an example of a textile covered (e.g., upholstered) piece
of furniture 181. In both cases, the substrate has areas 172, 182 contaminated with
dirt, stains, odours, etc. As the optical cleaning apparatus is scanned over the sample,
the apparatus removes contaminant particles from the textile fibers providing a cleaning
process. Equally, for the LIRON, the apparatus also provides the additional functionality
of crease removal.
[0121] An optional data bearing element (173 in FIGURE 16), such as a radio frequency identification
(RFID) tag or bar code, which can be integral with the article to be cleaned, can
include data for communication to the cleaning device, such as the LIRON, such data
comprising cleaning process parameters and /o r identification of the substrate material
composition (i.e., cotton, silk, wool, etc.). For example, an RFID tag or barcode
attached to a garment, containing information about the fabric type, can be read by
an appropriate sensor in communication with the LIRON, responsive to which the a cleaning
recipe, appropriate for the particular fabric type, can be followed responsive to
the communicated data. The sensor can be mounted with the LIRON, which can include
a processor, for processing or responding to the data and controlling the cleaning.
[0122] FIGURE 18 shows an optical cleaning apparatus based on a design similar to a flat-bed
scanner or photocopier. In this apparatus, the optical source 191, and beam steering
and beam shaping optics 192 of the optical transmission pathway can be within an enclosure.
The beam is directed upwards to the upper surface of the apparatus which is configured
as an optically transmissive window 193. In this example, the beam is focussed to
a spot at a point just above the window surface onto which the textile substrate can
be placed flat, such that the beam is focussed on the textile substrate. Similarly,
the beam could be in the form of a large spot for flood illumination or a stripe.
The beam is scanned across the surface of the transmissive window such that the surface
of the textile substrate is fully exposed to the beam during the scan process.
[0123] The apparatus includes a lid 194 which, when closed onto the fabric material, sandwiches
the material flat against the transmissive window. The lid can also act to form a
light-tight seal and provide the appropriate interlock safety features for, for example,
systems where the potential optical exposure exceeds acceptable safety limits. Further,
the lid can also provide suction, steam, water, gas, detergent, oxygen-based bleaching
agent, stain removal and any other form of cleaning assistance.
[0124] FIGURE 19 shows an apparatus 200 suited to large area cleaning within, for example,
industrial-scale cleaning process. In this apparatus, the substrate to be cleaned
201 is positioned flat and held in position. The apparatus includes an optical source
202 which provides an optical beam 203 which is beam shaped and directed onto the
substrate by a beam steering optic 204. The beam steering optic is on a translation
stage 205 which traverses horizontally across the substrate. The entire module of
the optical source, translation stage and beam steering / shaping optics is also movable,
along rollers 208, and traverses vertically (as shown in this specific example) such
that the optical beam can cover the entire surface of the textile substrate to remove
contaminants from contaminated regions of the substrate 206 to make the area clean
207.
[0125] It will be appreciated that the apparatus of FIGURES 18 and 19 can also include safety
features and microprocessor control systems (not shown) described elsewhere herein.
It will also be appreciated that the apparatus of FIGURES 18 and 19 can also include
additional mechanisms for improving the cleaning process such as the use of steam,
gas, detergents, vacuum or suction, stain removers and other types of cleaning assistance
mechanisms, as described in conjunction with other apparatus herein.
Working Examples
[0126] FIGURE 20 shows an example of a cotton fabric 300 having been contaminated with a
dark oil from an engineering workshop. The piece of fabric is contaminated with a
dark machine shop oil 302 and has been exposed to a pulsed laser source in a square
region of approximately 15x15mm dimension 304. The laser parameters include wavelength
1064nm, pulse duration 20 nanoseconds and pulse energy of 800uJ at a pulse repetition
rate of 25KHz. The output from the laser is focussed to spot diameter of approximately
30um and scanned across the sample in a square pattern. The sample was soaked in water
prior to cleaning which enhanced the process of contaminant removal.
[0127] FIGURE 21a shows another example of a cleaned fabric sample 310 comprising a blue
and white cotton shirt. The shirt, prior to cleaning with an apparatus and process
according to the present invention, 312 had been contaminated with an orange coloured
food stain 314. FIGURE 21a shows the stained shirt after several attempts to wash
it in a conventional laundry process using detergents and a mechanical, aqueous washing
machine. The same shirt, shown in FIGURE 21b, has been exposed to the laser cleaning
process using an arrangement similar to FIGURE 1, wherein the laser emitted short
pulses of light in the visible range of the spectrum. The laser parameters included
wavelength of 532nm, pulse duration of approximately 200 nanoseconds and pulse energy
of 200 up at a pulse repetition rate of 25 KHz. FIGURE 21d shows the same section
of the same shirt having no presence of the orange stain 322. This cleaning process
was achieved using a focussed spot diameter of the laser of approximately 30um in
diameter and was achieved with approximately 4 passes of the laser beam over the contaminated
region of the fabric. During the cleaning process, the fabric was wetted with water
periodically to ensure the fabric remained wet at all times during the cleaning process.
[0128] In another example, the laser source comprises a fiber laser having wavelength of
approximately 1064nm and delivering up to 20watts of average power in continuous wave
(non-pulsed) to the substrate. In this example, the substrate is partially immersed
in a solution comprising water and detergent, said detergent containing an oxygen-based
bleaching agent (sodium percarbonate though other similar agents can be used). The
beam is focussed to a spot of approximately 30micrometres in diameter, enabling a
high fluence to be attained within a reasonable depth of focus through the fabric
material. The fabric is contaminated with a stain such as red-wine, such as curry,
such as grass stain or any other type of conventional stain. The stain can be new
or can be an old stain having survived many previous cleaning attempts. On scanning
the beam across the stained area of the fabric substrate, the stain molecules are
removed and/or bleached by the combination of the optical energy and the detergent
solution, the optical energy providing a combination of localised heating to assist
the oxygen-based bleaching agent and/or enzyme and/or surfactant performance at removing
or bleaching the stain as well as providing energy to the contaminant molecules making
them more mobile and hence easier to remove and/or bleach. The beam is scanned over
the contaminated substrate area on one or more passes to remove or bleach the contaminant
or stain. For small levels of contamination, there is no need to replenish the detergent
solution. For larger amounts of contamination, the solution is repeatedly or continually
replaced, preventing the build-up of highly contaminated solution and subsequent re-absorption
of the contaminant by the substrate. In this case of high levels of contamination,
the detergent solution is preferably flowed repeatedly or continually over the substrate
as the optical beam is scanned during the cleaning process.
[0129] More particularly, FIGURE 22 shows samples of cotton material, contaminated with
different food stains including tea 322, curry and oil 336, red wine 340, and grass
344. The samples have all been exposed to the laser cleaning process using an arrangement
similar to Figure 1, wherein the laser emitted continuous wave light in the near Infra
Red region of the spectrum. The laser is a continuous wave fiber laser operating at
a wavelength of 1064nm, and an average power of approximately 20Watts. The beam of
the laser was focussed close to the surface of the fabric samples with a spot diameter
of approximately 30um and scanned line by line to cover a square 15mm×15mm region
of the fabric in a multi-pass process. During the process, the samples have been immersed
in a solution of detergent made using a commercial laundry powder comprising approximately
15% oxygen-based bleaching agent sodium percarbonate.
[0130] Figure 22 also shows the laser-exposed sections of the fabric samples respectively
334, 338, 342 and 346. In each case these samples were processed by 4-passes of the
laser scanning at 400mm per second with a hatching of approximately 40um. It was observed
during the processing that contaminant was removed on each pass of the laser scan
over the fabric sample. During each pass, the detergent solution was observed to change
in colour due to removed contaminant from the fabric. Following 4-passes of the laser
scan on the samples, the detergent solution was heavily discoloured and would result
in re-absorption of the contaminant within the fabric sample, degrading the overall
quality of the cleaning process. This result identifies a preferred solution of continuously
replenishing the detergent, be it in solution, solid or in vapour format. A further
observation from this process was that the cleaning quality was significantly reduced
when the fabric sample was immersed in the solution by more than approximately 1mm
to 2mm.
[0131] It is appreciated that the process examples described herein with reference to FIGURES
20-22 are examples and that the type of fabric, contaminant, laser wavelength, pulse
duration, spot size or shape, scan speed and scan parameters, such as the linear approach
to scanning, detergent and detergent application method can all be changed whilst
still falling within the scope of this current invention.
[0132] In the examples above, it is considered, as with the other embodiments herein, that
the laser source can comprise a high power, multi-mode laser diode having a wavelength
below 1000nm and delivering in excess of 100 Watts in a larger, 100um diameter focussed
spot.
[0133] It is also considered that the optical source can comprise a very high power lamp
such as a Xenon arc lamp which delivers greater than 100watts of broadband optical
power to a spot in excess of 100um in diameter focussed onto the substrate.
[0134] The forgoing parameters of pulse time duration, average power, pulse energy and wavelength
can be used in conjunction with any of other embodiments of the invention disclosed
herein.
[0135] It will be appreciated that the specific orientations used within these FIGURES to
demonstrate the apparatus functionality are by way of example only.
[0136] The present disclosure is directed to each individual feature, system, material,
and/or method described herein. In addition, any combination of two or more such features,
systems, materials, and/or methods, if such features, systems, materials, and/or methods
are not mutually inconsistent, is included within the scope of the present invention.
To avoid undue repetition, not all features are discussed in conjunction with every
aspect, embodiment or practice of the disclosure. Features described in conjunction
with one aspect, embodiment or practice are deemed to be includable with others absent
mutual inconsistency or a clear teaching to the contrary. In some instances, features
will be discussed generally rather than in detail in conjunction with a specific aspect,
embodiment or practice, and it is understood that such features can be included in
any aspect, embodiment or practice, again absent mutual inconsistency or a clear teaching
to the contrary.
[0137] Those of ordinary skill in the art will readily envision a variety of other means
for performing the functions and/or obtaining the results or advantages described
herein and each of such variations or modifications is deemed to be within the scope
of the present invention. More generally, those skilled in the art would readily appreciate
that all parameters, dimensions, materials and configurations described herein are
meant to be exemplary and that actual parameters, dimensions, materials and configurations
will depend on specific applications for which the teachings of the present invention
are used.
[0138] In the claims as well as in the specification above all transitional phrases such
as "comprising", "including", "carrying", "having", "containing", "involving" and
the like are understood to be openended. Only the transitional phrases "consisting
of" and "consisting essentially of" shall be closed or semi-closed transitional phrases.
Furthermore, statements in the specification, such as, for example, definitions, are
understood to be open ended unless otherwise explicitly limited.
[0139] The phrase "A or B" as in "one of A or B" is generally meant to express the inclusive
"or" function, meaning that all three of the possibilities of A, B or both A and B
are included, unless the context clearly indicates that the exclusive "or" is appropriate
(i.e., A and B are mutually exclusive and cannot be present at the same time). "At
least one of A, B or C" (as well as "at least one of A, B and C") reads on any combination
of one or more of A, B and C, including, for example the following: A; B; C; A & B;
A & C; B & C; A & B; as well as on A, B & C.
[0140] It is generally well accepted in patent law that "a" means "at least one" or "one
or more." Nevertheless, there are occasionally holdings to the contrary. For clarity,
as used herein "a" and the like mean "at least one" or "one or more." The phrase "at
least one" may at times be explicitly used to emphasize this point. Use of the phrase
"at least one" in one claim recitation is not to be taken to mean that the absence
of such a term in another recitation (e.g., simply using "a") is somehow more limiting.
Furthermore, later reference to the term "at least one" as in "said at least one"
should not be taken to introduce additional limitations absent express recitation
of such limitations. For example, recitation that an apparatus includes "at least
one widget" and subsequent recitation that "said at least one widget is colored red"
does not mean that the claim requires all widgets of an apparatus that has more than
one widget to be red. The claim shall read on an apparatus having one or more widgets
provided simply that at least one of the widgets is colored red. Similarly, the recitation
that "each of a plurality" of widgets is colored red shall also not mean that all
widgets of an apparatus that has more than two red widgets must be red; plurality
means two or more and the limitation reads on two or more widgets being red, regardless
of whether a third is included that is not red, absent more limiting explicit language
(e.g., a recitation to the effect that each and every widget of a plurality of widgets
is red).