[0001] The present invention relates to an IR illumination device and munitions comprising
the same.
[0002] Conventional IR (dark) illumination flares are typically illumination hand held rockets,
which contain a cool burning flare. The flare compositions are pyrotechnic compositions
which undergo chemical reactions, typically combustion. Whilst every effort is made
to reduce light output in the visible region, due to the nature of the reaction, some
visible light output is usually observed, and there may be smoke or other debris that
are visible.
[0003] According to a first aspect of present invention there is provided an IR illumination
munition device for selective activation where upon activation the device emits IR
radiation in the range of wavelengths of from 600nm to 900nm, the device comprising:
an electrical power source and an array of IR light emitting diodes (IR LEDs), to
emit the IR radiation.
[0004] Preferably, there is a plurality of light emission units each connected to the electrical
power source independently and said light emission units comprise the array of IR
light emitting diodes (IR LEDs), and a power converter unit for driving the array.
[0005] The device optionally further comprising
an operator interface, a control unit independently connected to each light emission
unit, the control unit comprising a processor and being operably connected to the
operator interface.
[0006] In a preferred arrangement, there is provided an IR illumination munition device
for selective activation where upon activation the device emits IR radiation in the
range of wavelengths of from 750nm to 900nm, the device comprising:
an electrical power source;
a plurality of light emission units each connected to the power source independently
and said light emission units comprising:
an array of IR light emitting diodes (IR LEDs), to emit the IR radiation;
a power converter unit for driving the array.
[0007] Further, the independent coupling of the control unit to each light emission unit,
and the provision of a power converter at each light emission unit, tends to provide
the device with redundancy in case a part fails in service.
[0008] The use of an IR LED, an IR light emitting diode, allows for a light source which
is not the product of a pyrotechnic reaction. Pyrotechnic compositions are hazardous,
which introduces logistics problems of storage and handling.
[0009] A yet further issue is that due to decomposition of the pyrotechnic material in conventional
IR flares, often due to moisture ingress, the conventional pyrotechnic IR compositions
may have a finite lifetime.
[0010] The IR LED may be selected to provide very specific wavelengths, with narrow bandwidths.
They have very low power consumption and may be easily integrated onto printed circuits
as parts of larger systems.
[0011] The range of wavelengths may be independently selected in the near IR, mid IR or
Far IR wavelength range. In one arrangement there is provided a first IR LED with
a first IR radiation wavelength, and a second IR LED with a second different IR radiation
wavelength.
[0012] In a further arrangement the array may comprises at least two different wavelength
IR light emitting diodes. The IR light emitting diodes may be specifically selected
to provide specific wavelengths to work with specific night vision optics. The array
and therefore specific IR light emitting diodes may be selectively activated depending
on the specific requirement.
[0013] The array may be any shape or arrangement, such as for example the IR LEDs may be
arranged linearly, random, helical, curved, patterned, within the device. The IR LEDs
may be located on the surface or in recessed portions in a housing, to provide protection.
[0014] The IR LEDs may be further covered with a layer, coating or sheath to provide protection
and/or ruggedness.
[0015] Each light emission unit may comprise a capacitive energy store and/or and inductive
energy store. Such an energy store may be tuned to deliver power in a particularly
responsive manner and so can therefore permit higher switching frequencies of the
light emitting element arrays.
[0016] There may be provided a capacitor charging means electrically interposed between
the power source and each capacitive energy store. The capacitor charging means may
be connected to the control unit.
[0017] The control unit may be configured for driving at least one of the arrays of light
emitting elements in a pulse mode when the device is activated such that in operation
the array of light emitting elements may switch between a high power output condition
and a low power output condition repeatedly. The pulse mode may be such that the array
of light emitting elements may switch between conditions at a predetermined frequency.
The low power output mode may be substantially zero watts.
[0018] Each array of IR LEDs may comprise at least 5, preferably more than 10, preferably
more than 20 IR LEDs.
[0019] The power source may be any electrical power source, such as for example an electrical
cell, fuel cell, capacitor, preferably a lithium ion battery.
[0020] The device may be a hand thrown device, such as a grenade. The device may form part
of a munition, such as for example a controlled descent payload capable of being launched
from a munition. The device may be attached to or form an integral part of a UAV.
The device may form part of an applique for attachment to a body or vehicle.
[0021] According to a further aspect of the invention there is provided an IR illumination
munition comprising a carrier, a fuze, a controlled descent payload, wherein the payload
comprises a device as defined herein.
[0022] The operator interface may be configured to enable selection between initiation modes.
The initiation modes may comprise any combination of: an instant initiation, a delayed
initiation, a wirelessly controlled initiation, such as for example, RF, NFC, Bluetooth,
or mechanical force, such as, for example from high-g forces from set-back or high
spin rates, which are well known in the art. For launched munitions, such as mortar,
shells our under gun launched grenades, the munition may comprise a fuze, which may
be set to determine the point of deployment of the payload comprising the device.
[0023] The operator interface may be configured to enable selection between activation modes.
The activation modes may comprise: a pulse mode where the IR light emitting elements
may switch between a high power output condition and a low power output condition
repeatedly or a continuous power output mode where the power output is substantially
constant. The pulse output may be used to provide a signal or basic communications,
instructions.
[0024] The device may also further comprise at least one LED or an array of LEDs whose output
is outside of the near IR and far IR regions, such as for example the visible light
region or UV.
[0025] So that the invention may be well understood, embodiments thereof shall now be described
with reference to the following figures, of which:
Figures 1 show an exploded side view of a shell comprising a device according to the
invention.
Figure 2 shows a cross section of the illumination payload device
Figure 3 shows a cross section along the axis of the shell in figure 1
Figure 4 shows the release sequence of the main parachute
Figure 5 shows the deployed and activated illumination device.
Figure 6 shows a three-dimensional representation of a device according to the present
invention;
Figure 7 shows a schematic diagram of a first embodiment of a device according to
the present invention;
Figure 8 shows a schematic diagram of a second embodiment of a device according to
the present invention;
[0026] Turning to figure 1 there is provided a shell 1, with a main body 5, which is manufactured
from a steel alloy. Located around the circumference of the main body 5 is a copper
driving band 4, which allows engagement with the rifling on the bore of a barrel,
so as to impart spin. A tail unit 2 is located at the aft of the main body 5. The
tail unit 2 is made from aluminium and contains a male threaded portion 3, which engages
with a reciprocal female threaded portion (not shown) located in the aft of the main
body 5. The illumination payload device 100 (see Fig 2), when located in the payload
cavity 10a, inside the main body, is retained in place by use of a locking ring 6,
which screws into the forward end of main body 5. The frangible ogive element 7 has
a frangible link 7a, in the form of an aluminium thread. The frangible ogive element
7 may be secured to the locking ring 6 or directly to the main body 5. The frangible
ogive element receives the expulsion charge 8 and fuze 9. Upon operation of the fuze
9, the expulsion charge 8 builds up pressure within the frangible ogive element and
at the bursting pressure the thread 3 shears and the illumination payload device 100
is expelled from the aft of the main body 5.
[0027] Figure 2 shows a modular illumination unit 10, comprising the illumination payload
assembly 100, with an electronic switch(or receiver for remote control) 11. The switch
after a predetermined period activates the device 29 (shown as 100 in Figure 6). When
the payload 100 is ejected the drogue parachute 27 functions and the parachute delay
device 21 causes the main parachute 28 to be deployed.
[0028] Figure 3 shows an illumination shell 20, with a main body 24 formed from a steel
alloy, with a driving band 26 located thereupon. A tail unit 12 is located at the
aft of the main body 24. The tail unit 12 is made from aluminium and contains a male
threaded portion 13, which engages with a reciprocal female threaded portion 14 located
at the aft of the main body 24.
[0029] The illumination payload device 100 is located in the payload cavity 15, and is retained
in place by use of a locking ring 16, which screws into the forward end of main body
24.
[0030] The frangible ogive element 17 has a frangible link 17a, in the form of an aluminium
thread, which is fastened to the locking ring 16. The frangible ogive element receives
the expulsion charge 18 and fuze 19. Upon operation of the fuze 19, the expulsion
charge 18 builds up pressure within the frangible ogive element and at the bursting
pressure the thread 13 shears and the illumination payload device 100 is expelled
from the aft of the main body 24.
[0031] The illumination payload device 100 is a modular illumination unit 10, which slides
into the payload cavity 15.
[0032] Figure 4 shows a drogue parachute 64 attached to the main parachute carrier 66 by
the carrier tether 65. The drogue parachute 64 is then discarded. The main parachute
63 remains attached to the payload apparatus 61, by means of the payload tether 67,
and the illumination payload device 100 is activated.
[0033] Figure 5, shows the controlled descent 70 of the illumination payload device 100,
under the control of the main parachute 74. The device during its descent illuminates
72 the target area of interest with IR LEDS, whilst ensuring that the payload device
100 remains intact and under the control of the main parachute, such that it mitigates
against collateral damage.
[0034] With reference to Figure 6 there is shown generally at 100 a handheld device. The
device 100 comprises a substantially cylindrical housing 130 which accommodates a
plurality of IR LEDs 102 arranged as IR LED arrays 120a, 120b. The housing 130 further
accommodates a power source 106, a means for adjusting its standing position 108,
a transceiver 110 for wireless control of the device, an array of ultracapacitors
114 (which may be arranged as a plurality of arrays), a power converter unit 116 (which
may be arranged as a plurality of converter units) for driving the IR LEDs, and a
control unit 118.
[0035] The housing 130 has a substantially circular front and back face which are substantially
parallel and separated by an interconnecting side wall surface. Incorporated into
the interconnecting side wall, the housing 130 has facets arranged to extend axially
between the substantially circular faces of the cylindrical housing 130. Each of these
facets has arranged at it an array of IR LEDs, such as IR LED array 120a. Further,
each facet is provided with a PIR sensor 124.
[0036] A manual switch 122 is provided at the back face of the housing for selectively switching
the device 100 between and 'on' mode (where the device 100 may emit IR light if so
instructed) and an 'off' mode (where the device 100 may not emit light).
[0037] Also provided at the back face of the housing 130 is an access panel or port 104
whereby either the power source 106 can be removed (and replaced), or a recharging
energy source can be coupled into the source 106 to recharge it.
[0038] In operation, the handheld device 100 may be picked up by an operator, switched manually
from the 'off' mode to the 'on' mode using switch 122 and subsequently thrown into
an environment. A subsequent instruction received from the wireless transceiver 110
(which may be delivered by a remote control retained by the operator) causes the battery
106 to transfer energy, via the power converter units 116 and/or ultracapacitors 114
to the IR LED arrays 120a and 120b, which then emit IR light to illuminate a scene
proximate to the device 100.
[0039] Figure 7 shows schematically a device 200, similar to device 100, where components
similar to components in device 100 are incremented by 100. For instance the IR LED
array 120a of the device 100 in Figure 6 is similar to the IR LED array 220a of device
200.
[0040] With reference to Figure 7, there is shown a device 200 provided with a plurality
of IR light emission units 201. Each of the light IR emission units 201 comprises
an ultracapacitor array 214, a power converter unit 216 and the IR LED array 220.
The ultracapacitor array 214 is connected to the power converter unit 216 which is
in turn connected to the IR LED array 220.
[0041] For instance, an IR light emission unit 201a comprises ultracapacitor array 214a,
connected to power converter unit 216a connected to IR LED array 220a.
[0042] The device 200 is further provided with an ultracapacitor charger 215 connected to
each of the arrays of ultracapacitors 214a, 214b and 214c. The ultracapacitor charger
215 is connected to a power source 206 such that the ultracapacitor charger 215 can
receive and manage power from the source 206. The ultracapacitor charger 215 is further
connected to a control unit 218 such that it may send and receive signals from the
control unit 218.
[0043] The control unit 218 is additionally connected to each of the power converter units
216a, 216b and 216 c such that it can send and receive signals to and from these units.
[0044] Still further, the control unit 218 is connected to various interface units, such
as a PIR sensor unit 224 and a wireless control unit 210 (which may be provided as
part of a broader operator interface including also a manual remote control unit)
such that the control unit 218 may act in dependence on signals received from these.
[0045] The control unit 218 comprises a signal generator (not shown) and/or clock for generating
a periodic signal that varies between an upper value and a lower value at a predetermined
frequency.
[0046] Each ultracapacitor array 214a, 214b, and 214c is driven by the ultracapacitor charger
215, under instruction from the control unit 218 such that the charging of the ultracapacitor
array is regulated such that should the IR LED array need activation at a predetermined
time, the ultracapacitor array is able to discharge through the power converter unit
216 into the IR LED array 220 (and thereby put the device 200 is a high power output
mode) in a predetermined manner.
[0047] In particular the ultracapacitor arrays may be driven to charge during one phase
of a cycle of the periodic signal generated at the control unit 218 and then may be
driven to discharge during the second phase of a cycle of the periodic signal.
[0048] Accordingly the IR LED arrays may be switched between a high power mode (i.e. as
the ultracapacitor array 214 discharges into the IR LED array 220) and a low power
mode (i.e. as the ultracapacitor array 214 is charged).
[0049] Figure 8 shows schematically a device 300, similar to device 100, where components
similar to components in device 100 are incremented by 200. For instance the IR LED
array 120a of the device 100 in Figure 1 is similar to the IR LED array 320a of device
300.
[0050] As such, with reference Figure 8 there is shown generally at 300 a further schematic
embodiment of a device. As compared with the Figure 7 embodiment, this device 300
tends to do away with the ultracapacitor arrays 214a, 214b, 214c and the associated
charger 215.
[0051] Thus in this Figure 8 embodiment, the light emission units 301 comprise a power converter
unit 316 connected to an IR LED array 320.
[0052] A power source 306 is connected to each of the power converters 316a, 316b and 316c.
A control unit 318 is connected to each of the power converters 316a, 316b and 316c.
The control unit 318 is also connected to various interface units, such as a PIR sensor
unit 324 and a wireless control unit 310 (which may be provided as part of a broader
operator interface including also a manual remote control unit) such that the control
unit 318 may act in dependence on signals received from these.
[0053] In operation, the device 300 activates at least one of the IR LED arrays 320a, 320b,
and 320c when the associated power converter unit 316a, 316b, or 316c is instructed
by a signal from the control unit 318 to pass electrical energy from the power source
306 to its associated IR LED array. With energy being transferred from the power source
306 to an IR LED array 302, the device 300 is placed in a high power mode of operation.
[0054] The instruction to pass energy between the power source 306 and some or all of the
IR LED arrays 320a, 320b, 320c may be in the form of a periodic signal having a first
phase of a cycle and a second phase of a cycle such that the first phase of the cycle
causes activation of the IR LED arrays 320a, 320b, 320c (i.e. electrical energy is
supplied to the IR LED arrays 320a, 320b, 320c) and the second portion of the cycle
causes deactivation (i.e. not electrical energy supplied to the arrays).
[0055] In general operation any of the devices 100, 200 or 300 may be used as follows.
[0056] An operator firstly identifies an enclosure, particularly a building, or an open
area containing targets.
[0057] The operator then throws or otherwise deploys the device into the building or open
area (having first set the device into the 'on' mode).
[0058] The operator then selects that the device be activated. This selection may be by
means of an instruction to the device issued, via an operator-held remote control
device, to the wireless transceiver. Alternatively this instruction may have been
made prior to deployment of the device by setting a countdown timer (using a clock
in the control unit) such that at the end of the countdown, the device is activated.
[0059] Upon activation the IR LED arrays are illuminated with IR radiation.
1. An IR illumination munition device for selective activation where upon activation
the device emits IR radiation in the range of wavelengths of from 750nm to 900nm,
the device comprising:
an electrical power source; an array of IR light emitting diodes to emit the IR radiation.
2. A device according to claim 1, wherein there are a plurality of light emission units
each connected to the electrical power source independently and said light emission
units comprise:
the array of IR light emitting diodes,
a power converter unit for driving the array.
3. A device according to claim 1 wherein the range of wavelengths is in the range of
from 750 to 800nm.
4. A device according to claim 1 or claim 2, wherein the array comprises at least two
different wavelength IR light emitting diodes.
5. A device according to any one of claims 2 to 4, further comprising an operator interface,
a control unit independently connected to each light emission unit, the control unit
comprising a processor and being operably connected to the operator interface.
6. A device according to any one of claims 2 to 5, wherein each light emission unit comprises
a capacitive and/or inductive energy store.
7. A device according to claim 5 or claim 6 wherein the control unit is configured for
driving at least one of the arrays of light emitting diodes in a pulse mode when the
device is activated such that in operation the array of IR light emitting diodes may
switch between a high power output condition and a low power output condition repeatedly.
8. A device according to claim 7 wherein the pulse mode is such that the array of IR
light emitting diodes may switch between conditions at a predetermined frequency.
9. A device according to any of the preceding claims wherein the power source is a lithium
ion battery.
10. A device according to claims 5 to 9, wherein the operator interface is configured
to enable selection between initiation modes.
11. A device according to claim 10 wherein the initiation modes comprise any combination
of: an instant initiation, a delayed initiation, a wirelessly controlled initiation,
or mechanical initiation.
12. A device according to any one of claims 10 to 11 wherein the operator interface is
configured to enable selection between activation modes.
13. A device according to any one of the preceding claims wherein the device is a hand
thrown device, a controlled descent payload capable of being launched from a munition,
a UAV, an applique for attachment to a body.
14. An IR illumination munition comprising a carrier, a fuze, a controlled descent payload,
wherein the payload comprises a device according to any one of the preceding claims.