[0001] This invention relates to a lens blocking and deblocking method and device for use
in adhering an optical lens to a lens blocking device employed with machining, grinding
and processing equipment in the generation of optical, namely ophthalmic, lenses.
[0002] The process of preparing optical or ophthalmic lenses begins usually with an unfinished
or semi-finished glass or plastic lens blank. Typically a semi-finished lens blank
has a finished polished front surface and an unfinished back surface. By grinding
away material from the back surface of the lens blank the required corrective prescription
is generated. Thereafter the surface having had the corrective prescription imparted
thereto is polished and the peripheral edge of the thus processed lens blank is provided
with a final desired contour thereby establishing a finished optical or ophthalmic
lens. According to other processing methods, the finished ophthalmic lens can be directly
processed from a lens blank using for example three directional machining. The lens
blank can be either a plastic or a glass lens blank.
[0003] It is necessary during these various processing operations to securely maintain the
lens blank in accurate alignment and in place on the lens blocking device. This procedure
is often referred to as "lens blocking".
[0004] Heretofore various materials were employed to secure the lens blank to the lens blocking
device. These materials include glues, pitch and low temperature fusible metal alloys.
The use of glues and pitch, in addition to being messy, suffers the further disadvantage
of generally being non-reusable or non-reclaimable. While the prior art use of low
temperature metal alloys eliminated some of these disadvantages experienced with the
use of glues and pitch, nonetheless, the use of these metal alloys, both in their
preparation and their reclamation caused significant environmental and health hazards
especially since these alloys were most often fabricated from such metals as cadmium,
tin, lead and bismuth. Of these metals, lead and cadmium are the most toxic. Lead
is strong protoplasmic poison and can be introduced into the body by ingestion, inhalation
and skin absorption. Cadmium poisoning is similar to lead in many ways and is introduced
into the body in the same way as lead. Like lead, cadmium is stored in the liver,
kidney and bone. Procedures for the formulation of such alloys and reclamation processes
so as to enable its re-use as a material to secure a lens blank to a lens block thus
exposes workers to serious environmental and health hazards. The formation of these
alloys often is accomplished through the use of powdered or particulate metals which
are subjected to a sintering and heat treating process. Fumes and/or dust particles
of these metals are released to the ambient atmosphere thereby creating environmental
and health hazards for those formulating these alloys. The same hazards exist for
those attempting to reclaim the used low temperature metal alloy blocking material.
[0005] To overcome these issues, organic low shrinkage materials have been developed to
be used as lens blocking materials.
[0006] Patent
US 6,036,313 in the name of 3M Innovative Properties Company discloses examples of compound families
suitable for lens blocking with thermoplastic materials and methods of holding a lens.
[0007] The disclosed blocking compositions have many advantages over traditional metal alloy
materials. For example, the lens blocking compositions are non-toxic, environmentally
safe, and preferably biodegradable. The materials preferably can be used with existing
processing equipment and may be recycled. An optical lens blocking device can be used
that comprises a solidified mass of a thermoplastic blocking composition. The blocking
composition is solid at 21°C and has a low melting or softening point.
[0008] However the inventors have noticed that separating the thermoplastic blocking composition
from the lens blank is an issue. This deblocking step comprises ordinarily a hammering
step and a crack is generated at the interface between the thermoplastic blocking
composition and the lens blank.
[0009] Said step needs an operator, is often made after separating the ophthalmic lens block
from the machine, is time consuming and may introduce defects on the final lens.
[0010] Accordingly, there remains a need for improving deblocking a lens secured to a lens
blocking device thanks to a thermoplastic material.
[0011] Thus, the goal of the present invention is to improve blocking and/or deblocking
methods to enhance the quality of resulting lens.
[0012] This object is obtained according to the invention by a method for blocking an optical
lens on a heat conducting holding unit comprising a bottom part to be inserted and
fixed in a lens machining tool and an upper part comprising an upper assembling surface
comprising the steps of:
- a) providing a first layer consisting of an adhesive tape on the upper assembling
surface of the holding unit;
- b) providing a second layer consisting of a layer comprising a thermoplastic material
arranged on said adhesive tape ;
- c) providing the optical lens with a third layer consisting of an adhesive tape arranged
on the bottom surface of said optical lens;
- d) placing the optical lens with the third layer on the second layer consisting of
the layer comprising the thermoplastic material when the thermoplastic material is
softened or melted.
[0013] The invention also relates to an optical lens blocking device comprising:
- a heat- conducting holding unit comprising a bottom part to be inserted and fixed
in a lens machining tool and an upper part comprising an upper assembling surface;
- a first layer consisting of an adhesive tape placed on the upper assembling surface
of the holding unit;
- a second layer consisting of a layer comprising a thermoplastic material stacked on
the first layer;
- a third layer consisting of an adhesive tape stacked on the second layer.
[0014] An optical lens can be placed on the third layer of said optical lens blocking device
before or after placing the third layer on the second layer consisting of a layer
comprising a thermoplastic material.
[0015] According to further embodiments of the lens blocking device of the invention, which
can be considered alone or in all possible combinations:
- the upper assembling surface of the holding unit is a spherical surface;
- the melting or softening point of the thermoplastic material of the second layer is
between 45°C and 75°C;
- the adhesive tapes have a pressure-sensitive adhesive surface arranged to contact
a bottom surface of an optical lens or the upper assembling surface of the holding
unit and a tack-free adhesion promoting surface arranged to contact the surfaces of
the second layer;
- the thickness of the second layer is between 0.5 mm and 2 mm, as for an example equal
or less to 1 mm.
[0016] The invention also relates to a method for deblocking an optical lens which bottom
surface is secured on a previously mentioned optical lens blocking device or according
to previously mentioned method for blocking, comprising the steps of:
- a) heating the holding unit so as to soften or melt the thermoplastic material of
the second layer;
- b) separating the bottom surface of the second layer form the upper surface of the
adhesive tape of the first layer;
- c) separating the bottom surface of the optical lens from the upper surface of the
adhesive tape of the third layer.
[0017] According to embodiments of the deblocking method, the method further comprises one
or two of following steps:
d) separating the bottom surface of the adhesive tape of the third layer from the
upper surface of the second layer;
e) separating the bottom surface of the adhesive tape of the first layer form the
upper assembling surface of the holding unit.
[0018] According to an embodiment of the deblocking method, step a) of the deblocking method
consists in heating only the bottom part of the holding unit.
[0019] This invention also relates to a method of machining, such as for example grinding
and/or polishing and/or edging and/or engraving, an optical lens comprising the steps
of:
- blocking the bottom surface of the optical lens on a previously mentioned optical
lens blocking device or according to previously mentioned method for blocking an optical
lens;
- inserting and fixing the bottom part of the holding unit in a lens machining tool;
- machining the upper surface of the optical lens and/or edging said optical lens;
- deblocking the machined optical lens according to previously mentioned deblocking
method.
[0020] According to the present invention, a "layer comprising a thermoplastic material"
is a layer of material that can melt or soften when being heated. A thermoplastic
material can be remelted or softened when heated and remoulded when cooling after
melting or softening. Most thermoplastics are high molecular weight polymers whose
chains associate through weak van der Waals forces (polyethylene); strong dipole-dipole
interactions and hydrogen bonding (nylon); or even stacking of aromatic rings (polystyrene).
Many thermoplastic materials are addition polymers; e.g., vinyl chain-growth polymers
such as polyethylene and polypropylene. The layer comprising a thermoplastic material
may also comprise additives (such as, for example, plasticizers, stabilizers, pigments,
...) and/or fillers (such as mineral and / or organic fillers, as for examples boron,
carbon, clay, glass, cellulose, metals, oxides, aramide, polyamide, ...; fillers may
be of different geometry, such as for example grains, lamella, short or long fibers,
...).
[0021] According to the present invention, an "optical lens" may be a lens which surfaces
have already been machined, a semi-finished lens blank with a polished front surface,
a lens blank with two unfinished surfaces.
[0022] The optical lens can be made for example, but not limited to, of plastic or glass.
More generally, any combination of material suitable to obtain an optical system may
be used. One or two surfaces of the optical lens may be coated.
[0023] Thus an "optical lens" of the invention can be every optical part that needs to be
machined, as for example to be cut and/or grinded and/or polished and/or edged and/or
engraved, in order to provide a machined optical lens.
[0024] A fully machined optical lens according to the present invention is for example an
ophthalmic lens which surfaces form an optical system that fits a desired prescription.
Said machined optical lens can be edged when blocked according to the present invention
or edged in a further processing step, as for an example edged by an eye care practitioner.
[0025] According to the present invention, a "heat conducting holding unit" is a holding
unit that can be inserted in the chuck or fixing part of a holding tool. Said holding
tool may be part of a lathe or other movement inducing machine. The holding unit of
the invention is heat conducting and can be a metallic part or any material suitable
to let the heat propagate through said material. According to an embodiment of the
present invention, the holding unit is made of aluminium alloy.
[0026] According to the present invention, selected fixing means are provided to fix an
optical lens on a holding unit.
[0027] Said fixing means consist of three stacked layers, where the first layer consists
of an adhesive tape, the second layer consists of a layer comprising a thermoplastic
material and the third layer consists of an adhesive tape. The selected stacked layers
afford a simple and efficient blocking device and/or method and afford easy deblocking,
namely when heating the holding unit so as to soften or melt the thermoplastic material
of the second layer. The optical lens can thus be blocked and/or deblocked without
damage and the inventors have noticed that ophthalmic lenses manufactured using the
blocking and/or deblocking method according to the present invention have undamaged
and quality reliable optical surfaces.
[0028] Furthermore the quantity of material of the second layer may be limited and said
material may be reused after deblocking the machined optical lens.
[0029] The layer comprising a thermoplastic material may be prepared as an independent layer
arranged on the first layer consisting of an adhesive tape and shaped on said tape
by soft heating or be poured from a warm device onto the upper surface of the first
layer consisting of an adhesive tape.
[0030] Non limited embodiments of the invention will now be described with reference to
the accompanying drawing wherein:
- figure 1 is a cross sectional view of an optical lens fixed on an optical lens blocking
device according to the present invention;
- figure 2 to 6 show successive steps of a deblocking method according to the present
invention.
[0031] Skilled artisans appreciate that elements in the figures are illustrated for simplicity
and clarity and have not necessarily been drawn to scale. For example, the dimensions
of some of the elements in the figures may be exaggerated relative to other elements
to help improve the understanding of the embodiments of the present invention.
[0032] The wording "upper" or "on" and "bottom" or "under" indicates positions relative
to the optical lens when it is arranged so as the edge of the optical lens to be machined
is substantially situated in a horizontal plane.
[0033] Said position is purely conventional and the optical lens can be machined in a non
horizontal position.
[0034] As shown on figure 1, an optical lens 100 is secured on a holding unit 200 thanks
to fixing means 300. The edge of said optical lens 100 is substantially situated in
a horizontal plane.
[0035] The upper surface 110 of the optical lens 100 is a surface to be machined, as for
an example to be grinded and/or polished. The optical lens 100 can be further edged.
[0036] The bottom surface 120 of the optical lens 100 contacts the upper surface of the
fixing means 300.
[0037] According to an embodiment, the optical lens 100 is a semi-finished lens blank and
the bottom surface 120 is a finished optical surface.
[0038] As for an example, the external diameter of the optical lens 100 is between 50 mm
and 100 mm, for example equal to 80 mm.
[0039] The holding unit 200 is a metallic part which comprises a bottom part 230, 220 and
an upper part 250.
[0040] The lower part 230 of bottom part comprises means to orientate the holding unit in
corresponding orientating means of a tool (not represented) of a lens machining unit
such as a lathe or another movement inducing machine. Said tool may be a chuck or
another fixing tool.
[0041] Internal surface 240 of the holding unit may contact an upper surface of said tool.
[0042] The bottom part of the holding unit also comprises a central part 220 which is a
cylindrical part to be squeezed by said fixing tool of the machining unit.
[0043] Upper part 250 has an external diameter larger than the diameter of the central part
220 and its bottom surface 255 may lay on the upper surface of the tool of the lens
machining unit and may comprise positioning means. The upper part 250 also comprises
an upper assembling surface 210.
[0044] As for an example the diameter of the upper part 250 is 70 mm, the diameter of the
central part 220 is 43 mm and the height of the holding unit 200 is between 20 and
30 mm.
[0045] Fixing means 300 are arranged between the upper assembling surface 210 and the bottom
surface 120 of the optical lens and consists of three stacked layers where:
- the first layer is an adhesive tape 330 which bottom surface 334 is fixed on upper
assembling surface 210;
- the second layer is a layer 310 of thermoplastic material which bottom surface 314
is arranged on the upper surface 332 of the adhesive tape 330;
- the third layer is an adhesive tape 320 which bottom surface 324 is arranged on the
upper surface 312 of the layer 310 of thermoplastic material;
- the bottom surface 120 of the optical lens is fixed on the upper surface 322 of the
adhesive tape 320.
[0046] According to an embodiment, the thermoplastic material of the second layer 310 melts
or softens at a low temperature, less than the temperature at which the material(s)
of the lens component may degrades or flows. Preferably the melting or softening point
of the thermoplastic material is between 45°C and 75°C. Suitable thermoplastic material
may be selected from the group consisting of polyesters, polyurethanes, ionomer resins
of ethylene copolymers, polyester-polysiloxane block copolymers, segmented copolyesters
and polyetheresters, ethylene vinyl acetate resins and copolymers, waxes, polycaprolactones,
and blends thereof.
[0047] Said thermoplastic material may comprise a homopolymer or copolymer of epsilon-caprolactone.
[0048] Examples of thermoplastic materials are given in previously cited patent
US 6,036,313 and are suitable for the present invention.
[0049] According to an embodiment, the adhesive tapes 320, 330 have a pressure-sensitive
adhesive surface and a tack-free adhesion promoting surface. The tapes 320, 330 assist
in the firm bonding of the optical lens 100 to the thermoplastic material layer 310
and to the holding unit assembling surface 210.
[0050] According to an embodiment, the tapes are conformable, that is, they follow the curvature
of the lens blanks without any wrinkles or air bubbles; and translucent, that is,
they permit light to pass there through. As a result, the lens may be visually aligned
in the appropriate device prior to blocking. Still further, when the tapes are removed
from the lens, they leave virtually no adhesive residue. Thus, messy and time consuming
cleaning operations need not be performed on the lens before it can be used.
[0051] Despite this clean removability, suitable tapes may exhibit excellent adhesion to
the optical lens, to the thermoplastic material and to the holding unit. Additionally,
the tapes may be able to withstand the shear forces encountered during the machining
operations. As a result, lenses are held in accurate position throughout these operations.
An added benefit offered by using an adhesive tape is the protection provided to the
optical lenses from thermal and mechanical shock.
[0052] The composition of the exposed surface of the tape (i.e., the non-adhesive surface
away from the optical lens or from the upper assembling surface of the holding unit)
may be selected so as to achieve the desired degree of adhesion with a particular
thermoplastic material.
[0053] Examples of suitable tapes are given in previously cited patent
US 6,036,313.
[0054] As for examples, tapes commercialized by the company 3M and referred as 1640 and
1641 are particularly suitable.
[0055] A 1641 adhesive tape commercialized by the company 3M comprises a baking made of
polyethylene film covered by an acrylate adhesive.
[0056] According to an embodiment of the present invention, the upper surface 312 of the
thermoplastic material layer 310 is heated, for example with UV or IR lamps, so as
to let a zone of the thermoplastic material layer melt or soften. The optical lens
100 is then placed onto the adhesive tape 320 arranged on the partly molten or soften
thermoplastic material layer and moderate pressure is applied onto the lens component.
The optical lens is securely blocked after the cooling of the thermoplastic material
and the optical lens is machined using conventional tools to provide grinding and/or
polishing and/or edging.
[0057] According to another embodiment of the present invention, the thermoplastic material
is previously heated and then poured on the upper surface 332 of the adhesive tape
330, the adhesive tape 320 is arranged on the upper surface 312 of the thermoplastic
material layer 310 and moderate pressure is applied on the optical lens 100 arranged
on said layer 310 when the thermoplastic material is still at least partly melted
or softened.
[0058] According to other embodiments of the present invention, the adhesive tape 320 is
previously arranged on the bottom surface 120 of the optical lens 100 and moderate
pressure is applied on the optical lens 100 with said adhesive tape 320 when the thermoplastic
material of layer 310 is at least partly melted or softened. Melting or softening
said thermoplastic material can be achieved by heating it, for example with UV or
IR lamps, or by pouring it when warm on the upper surface 332 of the adhesive tape
330.
[0059] After machining the optical lens, the machined optical lens is deblocked and detached
from the holding unit 200.
[0060] Consecutive deblocking steps are shown on figures 2 to 6 according to an embodiment
of the present invention.
[0061] The holding unit 200 is heated through heating means 400 on figure 2. Heating means
can be for example IR or UV lamps, as well as hot liquids, be provided by contacting
a heated metal part or by other conductive heating means.
[0062] According to an embodiment, only the bottom part of the holding unit 200, as for
an example the lower part 230 of the bottom part, is directly heated by the heating
means and the heat propagates then through the holding unit to the upper part 250
thanks to heat conduction.
[0063] It is thus possible to control precisely the heat amount brought to the layer of
thermoplastic material 310 and to avoid thermal shock on the optical lens 100. Optical
quality of the optical lens can thus be advantageously preserved.
[0064] Heating the holding unit 200 makes possible to deblock the optical lens without significant
heating of the optical lens.
[0065] After heating the bottom surface 314 of the thermoplastic material layer 310 thanks
to conductive heating through the holding unit 200, a zone of thermoplastic material
close to said surface 314 melts or softens and the separation of the thermoplastic
material layer 310 from the adhesive tape 330 is very easy when pulling according
to arrow 510 as shown on figure 3. The holding unit 200 and the first layer consisting
of the adhesive tape 330 remain together.
[0066] The optical lens 100, the third layer consisting of the adhesive tape 320 and the
thermoplastic material layer 310 remain together.
[0067] According to a further step illustrated on figure 4, the third layer consisting of
the adhesive tape 320 is peeled or pulled according to arrow 520 and the third layer
and the thermoplastic material layer remain together after being separated from the
optical lens 100.
[0068] The third layer consisting of the adhesive tape 320 can then be easily removed from
the upper surface 312 of the thermoplastic material layer 310 when said layer is pulled
according to arrow 530 as shown on figure 5. The thermoplastic material can be rapidly
reused to prepare another lens blocking device.
[0069] The first layer consisting of the adhesive tape 330 can be easily removed from the
upper assembling surface 210 of the holding unit 200 by peeling or pulling said adhesive
tape 330 according to arrow 540 as shown on figure 6.
[0070] The holding unit can be rapidly reused to prepare another lens blocking device.
[0071] Thanks to the adhesive tapes the thermoplastic material as well as the holding unit
are not contaminated during the blocking / machining / deblocking steps and are immediately
reusable.
[0072] The invention has been described above with the aid of embodiments without limitation
of the general inventive concept. In particular the present invention provides a method
for blocking and/or deblocking all kinds of optical lenses, particularly ophthalmic
lenses, e.g. single vision (spherical, torical), bi-focal, progressive, aspherical
lenses (etc..), semi-finished optical lenses and/or blanks, blanks for manufacturing
optical lenses.
1. A method for blocking an optical lens (100) on a heat conducting holding unit (200)
comprising a bottom part (220, 230) to be inserted and fixed in a lens machining tool
and an upper part (250) comprising an upper assembling surface (210) comprising the
steps of:
a) providing a first layer consisting of an adhesive tape (330) on the upper assembling
surface (210) of the holding unit;
and characterized in that it further comprises the steps of: b) providing a second layer consisting of a layer
(310) comprising a thermoplastic material arranged on said adhesive tape (330);
c) providing the optical lens (100) with a third layer consisting of an adhesive tape
(320) arranged on the bottom surface (120) of said optical lens;
d) placing the optical lens (100) with the third layer (320) on the second layer (310)
consisting of the layer comprising the thermoplastic material when the thermoplastic
material is softened or melted.
2. An optical lens blocking device comprising:
- a heat conducting holding unit (200) comprising a bottom part (220, 230) to be inserted
and fixed in a lens machining tool and an upper part (250) comprising an upper assembling
surface (210);
- a first layer consisting of an adhesive tape (330) placed on the upper assembling
surface (210) of the holding unit;
and
characterized in that it further comprises:
- a second layer consisting of a layer (310) comprising a thermoplastic.material stacked
on the first layer (330);
- a third layer consisting of an adhesive tape (320) stacked on the second layer (310).
3. The optical lens blocking device of preceding claim wherein the upper assembling surface
(210) of the holding unit is a spherical surface.
4. The optical lens blocking device of claims 2 or 3 wherein the melting or softening
point of the thermoplastic material of the second layer (310) is between 45°C and
75°C.
5. The optical lens blocking device of claims 2 to 4 wherein the adhesive tapes (320,
330) have a pressure-sensitive adhesive surface (322, 334) arranged to contact a bottom
surface (120) of an optical lens or the upper assembling surface (210) of the holding
unit and a tack-free adhesion promoting surface (324, 332) arranged to contact the
surfaces (312, 314) of the second layer (310).
6. The optical lens blocking device of claims 2 to 5 wherein the thickness of the second
layer (310) is between 0.5 mm and 2 mm, as for an example equal or less to 1 mm.
7. A method for deblocking an optical lens (100) which bottom surface (120) is secured
on an optical lens blocking device according to any of claims 2 to 6 or blocked according
to claim 1 comprising the steps of:
a) heating the holding unit (200) so as to soften or melt the thermoplastic material
of the second layer (310);
b) separating the bottom surface (314) of the second layer (310) from the upper surface
(332) of the adhesive tape (330) of the first layer;
c) separating the bottom surface (120) of the optical lens (100) from the upper surface
(322) of the adhesive tape (320) of the third layer.
8. The deblocking method of preceding claim further comprising the steps of:
d) separating the bottom surface (324) of the adhesive tape (320) of the third layer
from the upper surface (312) of the second layer;
e) separating the bottom surface (334) of the adhesive tape (330) of the first layer
from the upper assembling surface (210) of the holding unit.
9. The deblocking method of claims 7 or 8 wherein step a) of the deblocking method consists
in heating only the bottom part (220, 230) of the holding unit (200).
10. A method of machining an optical lens (100) comprising the steps of:
- blocking the bottom surface (120) of the optical lens (100) on an optical lens blocking
device of any of claims 2 to 6 or blocking according to claim 1;
- inserting and fixing the bottom part (220, 230) of the holding unit (200) in a lens
machining tool;
- machining the upper surface (110) of the optical lens (100) and/or edging said optical
lens (100);
- deblocking the machined optical lens according to any of claims 7 or 9.
1. Verfahren zum Halten einer optischen Linse (100) auf einer wärmeleitenden Halteeinheit
(200), welche ein Unterteil (220, 230), das in ein Linsenbearbeitungsgerät einzusetzen
und dort zu fixieren ist, und ein Oberteil (250) umfasst, welches eine obere Montagefläche
(210) umfasst, umfassend die Schritte:
a) Bereitstellen einer aus einem Klebeband (330) bestehenden ersten Schicht auf der
oberen Montagefläche (210) der Halteeinheit,
und dadurch gekennzeichnet, dass es ferner die Schritte umfasst:
b) Bereitstellen einer zweiten Schicht, welche aus einer ein thermoplastisches Material
umfassenden Schicht (310) besteht, die auf dem Klebeband (330) angeordnet ist,
c) Versehen der optischen Linse (100) mit einer aus einem Klebeband (320) bestehenden
dritten Schicht, welche an der unteren Fläche (120) der optischen Linse angeordnet
ist,
d) Anordnen der optischen Linse (100) mit der dritten Schicht (320) auf der zweiten
Schicht (310), die aus der Schicht besteht, welche das thermoplastische Material umfasst,
wenn das thermoplastische Material erweicht oder geschmolzen ist.
2. Halteeinrichtung für eine optische Linse, umfassend:
- eine wärmeleitende Halteeinheit (200), welche ein Unterteil (220, 230) umfasst,
welches in ein Linsenbearbeitungsgerät einzusetzen und dort zu fixieren ist, und ein
Oberteil (250) umfasst, welches eine obere Montagefläche (210) umfasst,
- eine aus einem Klebeband (330) bestehende erste Schicht, welche auf der oberen Montagefläche
(210) der Halteeinheit angeordnet ist,
und
dadurch gekennzeichnet, dass sie ferner umfasst:
- eine zweite Schicht, die aus einer ein thermoplastisches Material umfassenden Schicht
(310) besteht, welche auf die erste Schicht (330) gestapelt ist,
- eine aus einem Klebeband (320) bestehende dritte Schicht, welche auf die zweite
Schicht (310) gestapelt ist.
3. Halteeinrichtung für eine optische Linse nach dem vorhergehenden Anspruch, wobei die
obere Montagefläche (210) der Halteeinheit eine sphärische Fläche ist.
4. Halteeinrichtung für eine optische Linse nach Ansprüchen 2 oder 3, wobei der Schmelz-
oder Erweichungspunkt des thermoplastischen Materials der zweiten Schicht (310) zwischen
45 °C und 75 °C liegt.
5. Halteeinrichtung für eine optische Linse nach Ansprüchen 2 bis 4, wobei die Klebebänder
(320, 330) jeweils eine druckempfindliche Klebefläche (322, 334) aufweisen, die so
angeordnet sind, dass sie eine untere Fläche (120) einer optischen Linse oder die
obere Montagefläche (210) der Halteeinheit kontaktieren, und jeweils eine klebefreie,
Adhäsions-unterstützende Fläche (324, 332) aufweisen, die so angeordnet sind, dass
sie die Flächen (312, 314) der zweiten Schicht (310) kontaktieren.
6. Halteeinrichtung für eine optische Linse nach Ansprüchen 2 bis 5, wobei die Dicke
der zweiten Schicht (310) zwischen 0,5 und 2 mm liegt, beispielsweise kleiner oder
gleich 1 mm ist.
7. Verfahren zum Lösen einer optischen Linse (100), deren untere Fläche (120) an einer
Halteeinrichtung für eine optische Linse nach einem der Ansprüche 2 bis 6 angebracht
ist, oder die gemäß Anspruch 1 gehalten wird, umfassend die Schritte:
a) Heizen der Halteeinheit (200) um das thermoplastische Material der zweiten Schicht
(310) zu erweichen oder zu schmelzen,
b) Trennen der unteren Fläche (314) der zweiten Schicht (310) von der oberen Fläche
(332) des Klebebandes (330) der ersten Schicht,
c) Trennen der unteren Fläche (120) der optischen Linse (100) von der oberen Fläche
(322) des Klebebandes (320) der dritten Schicht.
8. Verfahren zum Lösen nach dem vorhergehenden Anspruch, ferner umfassend die Schritte:
d) Trennen der unteren Fläche (324) des Klebebandes (320) der dritten Schicht von
der oberen Fläche (312) der zweiten Schicht,
e) Trennen der unteren Fläche (334) des Klebebandes (330) der ersten Schicht von der
oberen Montagefläche (210) der Halteeinheit.
9. Verfahren zum Lösen nach Ansprüchen 7 oder 8, wobei Schritt a) des Verfahrens zum
Lösen darin besteht, nur das Unterteil (220, 230) der Halteeinheit (200) zu heizen.
10. Verfahren zum Bearbeiten einer optischen Linse (100) umfassend die Schritte:
- Halten der unteren Fläche (120) der optischen Linse (100) an einer Halteeinrichtung
für eine optische Linse gemäß einem der Ansprüche 2 bis 6, oder Halten nach Anspruch
1,
- Einsetzen und Fixieren des Unterteils (220, 230) der Halteeinheit (200) in ein Linsenbearbeitungsgerät,
- Bearbeiten der oberen Fläche (110) der optischen Linse (100) und/oder Schleifen
der optischen Linse (100),
- Lösen der bearbeiteten optischen Linse gemäß einem der Ansprüche 7 oder 9.
1. Procédé de blocage d'une lentille optique (100) sur une unité de maintien thermoconductrice
(200) comprenant une partie inférieure (220, 230) à insérer et à fixer dans un outil
d'usinage de lentille et une partie supérieure (250) comprenant une surface d'assemblage
supérieure (210) comprenant les étapes de :
a) la fourniture d'une première couche se composant d'un ruban adhésif (330) sur la
surface d'assemblage supérieure (210) de l'unité de maintien ;
et caractérisé en ce qu'il comprend en outre les étapes de :
b) la fourniture d'une deuxième couche se composant d'une couche (310) comprenant
un matériau thermoplastique agencé sur ledit ruban adhésif (330) ;
c) la fourniture à la lentille optique (100) d'une troisième couche se composant d'un
ruban adhésif (320) agencé sur la surface inférieure (120) de ladite lentille optique
;
d) le placement de la lentille optique (100) avec la troisième couche (320) sur la
deuxième couche (310) se composant de la couche comprenant le matériau thermoplastique
lorsque le matériau thermoplastique est assoupli ou fondu.
2. Dispositif de blocage de lentille optique comprenant :
- une unité de maintien thermoconductrice (200) comprenant une partie inférieure (220,
230) à insérer et à fixer dans un outil d'usinage de lentille et une partie supérieure
(250) comprenant une surface d'assemblage supérieure (210) ;
- une première couche se composant d'un ruban adhésif (330) placé sur la surface d'assemblage
supérieure (210) de l'unité de maintien ;
et
caractérisé en ce qu'il comprend en outre :
- une deuxième couche se composant d'une couche (310) comprenant un matériau thermoplastique
empilé sur la première couche (330) ;
- une troisième couche se composant d'un ruban adhésif (320) empilé sur la deuxième
couche (310).
3. Dispositif de blocage de lentille optique selon la revendication précédente, dans
lequel la surface d'assemblage supérieure (210) de l'unité de maintien est une surface
sphérique.
4. Dispositif de blocage de lentille optique selon la revendication 2 ou 3, dans lequel
le point de fusion ou d'assouplissement du matériau thermoplastique de la deuxième
couche (310) est entre 45°C et 75°C.
5. Dispositif de blocage de lentille optique selon l'une quelconque des revendications
2 à 4, dans lequel les rubans adhésifs (320, 330) ont une surface adhésive sensible
à la pression (322, 334) agencée pour entrer en contact avec une surface inférieure
(120) d'une lentille optique ou la surface d'assemblage supérieure (210) de l'unité
de maintien et une surface de promotion d'adhésion non collante (324, 332) agencée
pour entrer en contact avec les surfaces (312, 314) de la deuxième couche (310).
6. Dispositif de blocage de lentille optique selon l'une quelconque des revendications
2 à 5, dans lequel l'épaisseur de la deuxième couche (310) est entre 0,5 mm et 2 mm,
par exemple inférieure ou égale à 1 mm.
7. Procédé de déblocage d'une lentille optique (100) dont la surface inférieure (120)
est fixée sur un dispositif de blocage de lentille optique selon l'une quelconque
des revendications 2 à 6 ou bloquée selon la revendication 1, comprenant les étapes
de :
a) le chauffage de l'unité de maintien (200) afin d'assouplir ou de fondre le matériau
thermoplastique de la deuxième couche (310) ;
b) la séparation de la surface inférieure (314) de la deuxième couche (310) à partir
de la surface supérieure (332) du ruban adhésif (330) de la première couche ;
c) la séparation de la surface inférieure (120) de la lentille optique (100) à partir
de la surface supérieure (322) du ruban adhésif (320) de la troisième couche.
8. Procédé de déblocage selon la revendication précédente, comprenant en outre les étapes
de :
d) la séparation de la surface inférieure (324) du ruban adhésif (320) de la troisième
couche à partir de la surface supérieure (312) de la deuxième couche ;
e) la séparation de la surface inférieure (334) du ruban adhésif (330) de la première
couche à partir de la surface d'assemblage supérieure (210) de l'unité de maintien.
9. Procédé de déblocage selon la revendication 7 ou 8, dans lequel l'étape a) du procédé
de déblocage se compose du chauffage uniquement de la partie inférieure (220, 230)
de l'unité de maintien (200).
10. Procédé d'usinage d'une lentille optique (100) comprenant les étapes de :
- le blocage de la surface inférieure (120) de la lentille optique (100) sur un dispositif
de blocage de lentille optique selon l'une quelconque des revendications 2 à 6 ou
le blocage selon la revendication 1 ;
- l'insertion et la fixation de la partie inférieure (220, 230) de l'unité de maintien
(200) dans un outil d'usinage de lentille ;
- l'usinage de la surface supérieure (110) de la lentille optique (100) et/ou le détourage
de ladite lentille optique (100) ;
- le déblocage de la lentille optique usinée selon la revendication 7 ou 9.