Patent Description:
References considered to be relevant as background to the presently disclosed subject matter are listed below.

<CIT>, discloses modifying a ship's infra-red appearance by determining the infra-red image of the ships surroundings and reflecting infrared radiation from its surroundings by reflector means pivotable about pivot points to cause the ship to merge into its surroundings. Because the reflector means are pivotable the way in which the ships infra-red appearance is modified can be controlled and the infra-red appearance can be made to correspond to the ships background when viewed along the line of sight of a likely threat, thus making it difficult to detect by a heat-seeking missile. The reflector means may be coated with bands of material translucent to infra-red radiation but opaque to visible radiation, to make it inconspicuous, and may comprise an inflatable envelope with a reflective surface.

<CIT>, discloses an apparatus for altering the IR characteristics of a body comprising a surface having at least two discrete areas possessing different IR characteristics, masking means for masking different portions of the surface, and controlling means for operating the masking means arranged such that operation of the controlling means alters the relative exposures of the two or more areas of the surface such as to impart desirable IR characteristics to an aspect of the body as detected from a remote point. In particular, an IR signaling apparatus comprising an inelastic surface composed of alternating low IR emissivity elements and high emissivity elements. The inner face of the surface is bonded to a body while the outer face is bonded to a polythene core which is divided into individual nitrogen-filled chambers. Masking means in the form of parallel inelastic strips are bonded to the outer face of the core. These strips have an inner side which is composed of low IR emissivity material and an outer side composed of medium to low IR emissivity material also colored in the visible. The apparatus is mounted on a body for signaling to a remote detector. The masking means is located above the surface so as to achieve a desired overall IR characteristic, and relative motion is introduced between the two at a known frequency. The detector is filtered at this frequency.

<CIT>, discloses a means of reflecting and emitting electromagnetic energy in an appropriate wavelength band comprising an arrangement of surfaces which are reflective to energy in that wavelength band and energy emitters having an emission of energy of such intensity that the combined reflection and emission of said surfaces match energy of a background in that wavelength band thereby camouflaging the surfaces. The said emitters comprise strips of material which, upon energizing with an electric current, become heated and radiate energy. The means further comprises at least one radiometer in association with a comparison means to provide an electrical signal which is a function of the difference between the combined reflection and emission and of the background, the electrical signal controlling the energization of the energy emitters.

<CIT>, discloses an infrared camouflage device having a surface structure with two groups of partial areas. Partial areas in the first group are directed downward and form an angle α of between <NUM>° and <NUM>° with vertical; and partial areas in the second group are directed upward and form an angle β of between <NUM>° and <NUM>° with vertical; and α+β<<NUM>°.

<CIT>, discloses a sheet of thermally reflective material having a surface texture comprising a plurality of reflecting elements, wherein each element has a first facet which is substantially reflective at thermal infrared wavelengths and wherein the respective first facets form an angle θ with the plane of the sheet (A-B) (<NUM>°<θ<<NUM>°). Preferably, the first facets are aligned such that, in use, thermal radiation is reflected from a common direction. By orienting the sheet of thermally reflective material to reflect cold regions of the sky, a marking material exhibiting a cold spot in a thermal imager can be provided.

"<NPL>, discloses camouflage techniques corresponding to adaptation strategies to the surrounding environment. In conflict zones, these strategies allow a soldier or a vehicle to gain a decisive advantage over the enemy. In addition to the mimicry in the visible spectrum, we should also able to control the reflected infrared IR radiance (thermal signature), in order not to be detected by observing systems, such as infrared cameras. A solution for this issue is the use of elements with a controlled IR reflection, which allows to mitigate this signature. Liquid crystal materials have compatibilities with this function through its electrooptic properties. The objective is to study the possibilities to control the reflectivity of a liquid crystal cell in the infrared spectrum. Three mechanisms using liquid crystal are identified.

<CIT>, discloses a device for signature adaptation, comprising at least one surface element arranged to assume a determined thermal distribution, wherein said surface element comprises at least one temperature generating element arranged to generate at least one predetermined temperature gradient to a portion of said at least one surface element. Said at least one surface element comprises at least one radar suppressing element, wherein said at least one radar suppressing element is arranged to suppress reflections of incident radio waves. The invention also concerns an object provided with a device for signature adaptation.

<CIT>, discloses camouflage in both the visual spectrum and the infrared spectrum by emulating the infrared radiation of an object's background and the visible radiation of an object's background, effectively cloaking the object from detection. Initially, the temperature and color of the background against which an object appears is determined. The external surface of the object, or alternatively a shield around the object, is then heated or cooled using thermoelectric modules that convert electrical energy into a temperature gradient. The ability of the modules to be either cooled or heated permits the output of the modules to be altered to match the temperature of an object's background. In combination with these thermocouples, the invention utilizes choleric liquid crystals to alter the visible color of an object. Since the visible color of choleric liquid crystals can be changed with temperature, the heating and cooling ability of the thermocouples can be used to adjust the color of the liquid crystals to match the object's background color.

<CIT>, discloses a method for visually adaptively camouflaging objects, the background and/or the surroundings in front of which and/or in which the object is situated are/is detected by means of a camera or a sensor array. The background and/or the surroundings thus detected are/is reproduced as an image in a device for camouflaging the object.

<CIT>, discloses a system for the adaptive camouflage of objects, particularly of vehicles, at least one panel-like layer is provided, which is at least partially air-permeable. The air suctioned in from the surroundings can be controlled, before or while it is fed into the layer, to a temperature that is determined at least almost from the background of the object.

"<NPL>, discloses that camouflage has historically been an important survivability technique for battlefield platforms, installations and personnel. In World War I, camouflage was developed as handcrafted disruptive patterns, unique to each soldier, platform or installation. World War II saw the development of industrially produced patterned camouflage textiles for uniforms and nets. The modern battlefield presents new challenges for the traditional methods of camouflage. Modern sensors are able to resolve very small differences between targets and background, and a traditional static camouflage solution will only maintain a close enough match to its environment if the environment also remains static. To maintain low detectability in a changing environment, camouflage systems must adapt. This research demonstrates concepts of adaptive camouflage for a light armored vehicle (a Canadian Coyote) in a desert environment. Three techniques are investigated. A heat shield cover to reduce thermal signature and solar heat transfer into the vehicle, electro-chromic cells to simulate a chameleon-like behavior in the visual spectrum, and active thermal cells to create dynamic disruptive thermal patterns on the heat shield. The overall objective is to create a system to reduce conspicuity across the visual and infrared spectrum by disrupting the vehicle silhouette and minimizing the difference between the background and vehicle characteristics. This paper presents results from recent proof-of-concept testing.

"<NPL>, discloses that adaptive camouflage in thermal imaging, a form of cloaking technology capable of blending naturally into the surrounding environment, has been a great challenge in the past decades. Emissivity engineering for thermal camouflage is regarded as a more promising way compared to merely temperature controlling that has to dissipate a large amount of excessive heat. However, practical devices with an active modulation of emissivity have yet to be well explored. The publication demonstrates an active cloaking device capable of efficient thermal radiance control, which consists of a vanadium dioxide (VO2) layer, with a negative differential thermal emissivity, coated on a graphene/carbon nanotube (CNT) thin film. A slight joule heating drastically changes the emissivity of the device, achieving rapid switchable thermal camouflage with a low power consumption and excellent reliability.

<CIT>, discloses a camouflage material comprising an electromagnetic energy (EME) absorbing layer comprising an array of carbon nanotubes and a plurality of energy transmitting elements embedded within the absorbing material. The energy transmitting elements are operative to convey energy to at least a portion of an outer surface of the absorbing layer.

Document <CIT> discloses active infrared camouflage structure based on vanadium dioxide, which includes a heat substrate, a vanadium dioxide film and electrode pair. Vanadium dioxide film coats or is vaporized on heating the upper surface of the substrate. Heating substrate changes the temperature of vanadium dioxide film by electric current heating while providing support for vanadium dioxide film. A carbon nanotube graphene film is disclosed as a substrate choice.

The invention is set out in appended claims.

In accordance with a first aspect of the presently disclosed subject matter, there is provided a thermal signature generating device, the device comprising: at least one thermal radiation emitting element, each of the at least one thermal radiation emitting elements extending between two spaced-apart opposite solid surfaces defined by two opposite electrodes, wherein only opposite ends of the thermal radiation emitting element each contact one of said opposite solid surfaces, and comprising an array of Carbon Nanotubes (CNTs), the array being connected by its two opposite ends to the two opposite electrodes, respectively, and extending along a space between the electrodes, the electrodes providing electrical current through the thermal radiation emitting element, causing the thermal radiation emitting element to emit thermal radiation for generating the thermal signature.

In the invention, a majority of a surface area of the thermal radiation emitting element is not in contact with any solid surface.

In some cases, the array of CNTs is configured with an aspect ratio between cross-sectional dimensions of two surface regions of the two electrodes on which the ends of the array are mounted and a length of the array defined by the space between the electrodes, the cross sectional dimension of each of the two surface regions being larger than the space between the electrodes.

In some cases, the electrical current through the thermal radiation emitting element flows along a direction between the electrodes in alignment with the lengths of fibers of the CNTs.

In some cases, the electrodes are configured to serve as heat sinks for removing heat generated by the thermal radiation emitting element.

In some cases, the device further comprises a control unit configured and operable to generate control signals to control the electrical current through said at least one thermal radiation emitting element in accordance with the thermal signature to be generated, the control signals having a predetermined pattern corresponding to at least a predetermined temporal modulation of the electrical current.

In some cases, the device further comprises a housing comprising the electrodes and the thermal radiation emitting element, and wherein at least part of the housing enables thermal radiation passage therethrough.

In some cases, the housing further comprises at least one heat sink for removing heat generated by the thermal radiation emitting element.

In some cases, the housing provides a vacuumed environment for the thermal radiation emitting element.

In some cases, the at least part of the housing that enables thermal radiation passage therethrough is made of one or more of the following materials: germanium, Teflon, silicon, zinc selenide or polyethylene.

In some cases, a shape of the thermal radiation emitting element is a flat surface, and the housing comprises a marking instructing a user of a connection direction of connecting the housing to a fuse holder for providing thermal radiation at desired directions.

In some cases, the thermal radiation emitting element has one of the following shapes: a spiral, a cylinder, a fiber or a flat surface.

In some cases, the housing is shaped as a fuse enabling detachably connecting the housing to a fuse holder.

In some cases, the housing and the fuse holder meet the DIN <NUM> standard.

In some cases, the fuse holder is capable of providing the electrical current to the electrodes.

In some cases, the fuse holder comprises a reflector for directing the thermal radiation towards desired directions.

In some cases, the fuse holder is connected to a reflective surface for reflecting the thermal radiation towards desired directions.

In some cases, upon connecting the housing to the fuse holder, the housing is located within a substrate of the reflective surface, the substrate being designed to reflect the thermal radiation towards the desired directions.

In some cases, the device further comprises a male connector enabling detachably connecting the device to a female connector irrespective of an angle of rotation of the male connector around an axis of the male connector perpendicular to the female connector.

In some cases, the at least one thermal radiation emitting element is a plurality of thermal radiation emitting elements, wherein each thermal radiation emitting element of the plurality of thermal radiation emitting elements emits thermal radiation in a given direction, so that at least one of the thermal radiation emitting elements emits first thermal radiation in a first direction and at least another one of the thermal radiation emitting elements emits second thermal radiation in a second direction, other than the first direction.

In some cases, the pattern is a pre-defined pattern.

In some cases, the thermal signature is generated for marking one or more objects.

In some non-claimed cases, the device further comprises a thermographic camera capable of determining a heatmap of an area of interest, and the pattern is generated to match the heatmap.

In some non-claimed cases, the pattern is generated in order to camouflage an object located between a viewer and the area of interest.

In accordance with a second aspect of the presently disclosed subject matter, there is provided a thermal signature generating method, the method comprising: providing electrical current through at least one thermal radiation emitting element, causing the at least one thermal radiation emitting element to emit thermal radiation for generating a thermal signature, wherein each of the at least one thermal radiation emitting elements extends between two spaced-apart opposite solid surfaces defined by two opposite electrodes, wherein only opposite ends of the thermal radiation emitting element each contact one of said opposite solid surfaces, and comprises an array of Carbon Nanotubes (CNTs), the array being connected by its two opposite ends to the two opposite electrodes, respectively, and extending along a space between the electrodes, the electrodes providing the electrical current through the thermal radiation emitting element.

In some cases, the method further comprises: generating control signals to control the electrical current through the at least one thermal radiation emitting element in accordance with the thermal signature to be generated, the control signals having a predetermined pattern corresponding to at least a predetermined temporal modulation of the electrical current.

In some cases, the electrodes and the thermal radiation emitting element are included within a housing, and wherein at least part of the housing enables thermal radiation passage therethrough.

In some cases, the method further comprises: removing heat, generated by the thermal radiation emitting element, by at least one heat sink of the housing.

In some cases, the electrical current is provided to the electrodes by the fuse holder.

In some non-claimed cases, a thermographic camera is capable of determining a heatmap of an area of interest, and the pattern is generated to match the heatmap.

In some non-claimed cases, the pattern is generated in order to camouflage an object located between a viewer and the area of interest. There is also provided a non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code, executable by a controller of a computer to perform, at least partly, a thermal signature generating method, the method comprising: providing electrical current through at least one thermal radiation emitting element, causing the at least one thermal radiation emitting element to emit thermal radiation for generating a thermal signature, wherein each of the at least one thermal radiation emitting elements extends between two spaced-apart opposite solid surfaces defined by two opposite electrodes, wherein only opposite ends of the thermal radiation emitting element each contact one of said opposite solid surfaces, and comprises an array of Carbon Nanotubes (CNTs), the array being connected by its two opposite ends to the two opposite electrodes, respectively, and extending along a space between the electrodes, the electrodes providing the electrical current through the thermal radiation emitting element.

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the presently disclosed subject matter. However, it will be understood by those skilled in the art that the presently disclosed subject matter may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the presently disclosed subject matter.

Unless specifically stated otherwise, as apparent from the following discussions, it is appreciated that throughout the specification discussions utilizing terms such as "generating", "receiving", "emitting", "removing", "connecting", "instructing", "directing", "reflecting", "controlling" or the like, include action and/or processes of a computer that manipulate and/or transform data into other data, said data represented as physical quantities, e.g. such as electronic quantities, and/or said data representing the physical objects. The terms "computer", "processor", and "controller" should be expansively construed to cover any kind of electronic device with data processing capabilities, including, by way of non-limiting example, a personal desktop/laptop computer, a server, a computing system, a communication device, a smartphone, a tablet computer, a smart television, a processor (e.g. digital signal processor (DSP), a microcontroller, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), etc.), a group of multiple physical machines sharing performance of various tasks, virtual servers co-residing on a single physical machine, any other electronic computing device, and/or any combination thereof.

The operations in accordance with the teachings herein may be performed by a computer specially constructed for the desired purposes or by a general-purpose computer specially configured for the desired purpose by a computer program stored in a non-transitory computer readable storage medium. The term "non-transitory" is used herein to exclude transitory, propagating signals, but to otherwise include any volatile or non-volatile computer memory technology suitable to the application.

As used herein, the phrase "for example," "such as", "for instance" and variants thereof describe non-limiting embodiments of the presently disclosed subject matter. Reference in the specification to "one case", "some cases", "other cases" or variants thereof means that a particular feature, structure or characteristic described in connection with the embodiment(s) is included in at least one embodiment of the presently disclosed subject matter. Thus, the appearance of the phrase "one case", "some cases", "other cases" or variants thereof does not necessarily refer to the same embodiment(s).

It is appreciated that, unless specifically stated otherwise, certain features of the presently disclosed subject matter, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the presently disclosed subject matter, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

In embodiments of the presently disclosed subject matter, fewer, more and/or different stages than those shown in <FIG> may be executed. <FIG> illustrate general schematics of the system architecture in accordance with an embodiment of the presently disclosed subject matter. Each module in <FIG> can be made up of any combination of software, hardware and/or firmware that performs the functions as defined and explained herein. The modules in <FIG> may be centralized in one location or dispersed over more than one location. In other embodiments of the presently disclosed subject matter, the system may comprise fewer, more, and/or different modules than those shown in <FIG>.

Any reference in the specification to a method should be applied mutatis mutandis to a system capable of executing the method.

Any reference in the specification to a system should be applied mutatis mutandis to a method that may be executed by the system.

Attention is now drawn to <FIG>, a block diagram schematically illustrating one example of a thermal signature generation unit that constitutes thermal signature generating device <NUM>, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, thermal signature generating device <NUM> can be configured to generate a thermal signature.

Thermal signature generating device <NUM> can be configured to include a thermal radiation emission device <NUM>. Thermal radiation emission device <NUM> can be configured to include at least one thermal radiation emitting element <NUM>. In some cases, thermal radiation emission device <NUM> can be configured to include one thermal radiation emitting element <NUM>, as illustrated in <FIG>. Alternatively, in some cases, thermal radiation emission device <NUM> can include a plurality of thermal radiation emitting elements <NUM>, as detailed further herein, inter alia with reference to <FIG>, <FIG> and <FIG>.

Each of the at least one thermal radiation emitting elements <NUM> can be configured to extend between two spaced-apart opposite solid surfaces defined by two opposite electrodes. Moreover, each of the at least one thermal radiation emitting elements <NUM> can be connected by its two opposite ends to the two opposite electrodes, respectively, and can extend along a space between the electrodes, as detailed further herein, inter alia with reference to <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG> and <FIG>.

In some cases, each of the at least one thermal radiation emitting elements <NUM> can comprise an array of Carbon Nanotubes (CNTs), the array being connected by its two opposite ends to two opposite electrodes, respectively, between which the respective thermal radiation emitting element <NUM> extends, and extending along the space between the electrodes, as detailed further herein, inter alia with reference to <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG> and <FIG>. Additionally, or alternatively, in some cases, each of the at least one thermal radiation emitting elements <NUM> can be manufactured from one or more of: stainless steel, aluminum or nickel. In some cases, each of the at least one thermal radiation emitting elements <NUM> can be one or more resistors. In some cases, each of the at least one thermal radiation emitting elements <NUM> can be configured to have one of the following shapes: a spiral, a cylinder, a fiber or a flat surface.

In the invention, a majority of a surface area of each of the at least one thermal radiation emitting elements <NUM> is not in contact with any solid surface, as detailed further herein, inter alia with reference to <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG> and <FIG>.

In some cases, as detailed further herein, inter alia with reference to <FIG>, <FIG>, <FIG>, <FIG> and <FIG>, the array of CNTs can be configured with an aspect ratio between cross-sectional dimensions of two surface regions of the two electrodes on which the ends of the array are mounted and a length of the array defined by the space between the electrodes, the cross sectional dimension of each of the two surface regions being larger than the space between the electrodes.

Thermal radiation emission device <NUM> can be further configured to include a housing <NUM> that holds one or more of the thermal radiation emitting elements <NUM>, as detailed further herein, inter alia with reference to <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG> and <FIG>. In some cases, thermal radiation emitting elements <NUM> can be included within housing <NUM>, as detailed further herein, inter alia with reference to <FIG> and <FIG>.

Housing <NUM> can be configured to include an electrical interface <NUM>. Electrical interface <NUM> can be configured to include, for each of the at least one thermal radiation emitting elements <NUM>, the two opposite electrodes between which the respective thermal radiation emitting element <NUM> extends and two electrical connections that are connected to the two opposite electrodes, respectively. Non-limiting examples of an electrical interface <NUM> are provided further herein, inter alia with reference to <FIG>, <FIG>, <FIG>, <FIG> and <FIG>. Electrical interface <NUM> can be configured to receive an electrical current. The electrodes of the electrical interface <NUM> that are associated with a respective thermal radiation emitting element <NUM> can provide electrical current through the thermal radiation emitting element <NUM>, causing the thermal radiation emitting element <NUM> to emit thermal radiation for generating the thermal signature.

In some cases, in which each of the at least one thermal radiation emitting elements <NUM> comprises an array of CNTs, the electrical current through a respective thermal radiation emitting element <NUM> can flow along a direction between the electrodes associated with the respective thermal radiation emitting element <NUM>, in alignment with the lengths of fibers of the CNTs.

In some cases, housing <NUM> can be further configured to include at least one thermally transparent body <NUM>, being at least part of the housing <NUM> and enabling thermal radiation passage therethrough. In some cases, the at least one thermally transparent body <NUM> can be made of one or more of the following materials: germanium, Teflon, silicon, zinc selenide or polyethylene. A non-limiting example of the at least one thermally transparent body <NUM> is a thermally transparent sleeve, as detailed further herein, inter alia with reference to <FIG>.

In some cases, housing <NUM> can also be configured to include at least one heat sink <NUM> for removing heat generated by thermal radiation emitting element <NUM>. In some cases, the at least one heat sink <NUM> can include a first pair of heat sinks and a second pair of heat sinks, as detailed further herein, inter alia with reference to <FIG>. In some cases, the electrodes can be configured to serve as heat sinks for removing heat generated by the thermal radiation emitting element, as detailed further herein, inter alia with reference to <FIG>, <FIG>, <FIG> and <FIG>.

In some cases, housing <NUM> can be configured to surround thermal radiation emitting element <NUM>, as detailed further herein, inter alia with reference to <FIG>. Additionally, in some cases, housing <NUM> can be configured to provide a vacuumed environment for thermal radiation emitting element <NUM>.

In some cases, housing <NUM> can be shaped as a cylindrical fuse (such a housing <NUM> is referred to hereinafter as a "fuse-shaped housing"). A non-limiting example of a fuse-shaped housing <NUM> is detailed further herein, inter alia with reference to <FIG>. By shaping the housing as a cylindrical fuse, the housing can be detachably connected to a fuse holder <NUM>, as detailed below.

Thermal signature generating device <NUM> can be configured to include a control unit <NUM>. Control unit <NUM> can be configured and operable to generate control signals to control the electrical current through the at least one thermal radiation emitting element <NUM> in accordance with the thermal signature to be generated, the control signals having a predetermined pattern corresponding to at least a predetermined temporal modulation of the electrical current.

In some cases, thermal radiation emission device <NUM> can be configured to include a control unit <NUM>, as detailed further herein, inter alia with reference to <FIG>, <FIG>, <FIG>, <FIG> and <FIG>. Alternatively, in some cases, in which thermal signature generating device <NUM> is configured to include a plurality of thermal radiation emission devices <NUM>, thermal signature generating device <NUM> can be configured to include a control unit <NUM> that is associated with the plurality of thermal radiation emission devices <NUM>.

In some cases in which thermal signature generating device <NUM> includes a plurality of thermal radiation emitting devices <NUM>, and accordingly a corresponding plurality of thermal radiation emitting elements <NUM>, each thermal radiation emitting element <NUM> of the plurality of thermal radiation emitting elements <NUM> can be configured to emit thermal radiation in a given direction, so that at least one of the thermal radiation emitting elements <NUM> emits first thermal radiation in a first direction and at least another one of the thermal radiation emitting elements <NUM> emits second thermal radiation in a second direction, other than the first direction.

In some cases, the generation of the control signals to control the electrical current through the at least one thermal radiation emitting element <NUM> can be performed by a user of the thermal signature generation unit <NUM>, for example, by the user manually opening and closing a switch.

In some cases, thermal signature generating device <NUM> can be configured to include a holder <NUM> for holding thermal radiation emission device <NUM>, as detailed further herein, inter alia with reference to <FIG> and <FIG>. In some cases, holder <NUM> can be configured to include a reflector <NUM>, as detailed further herein, inter alia with reference to <FIG> and <FIG>.

In some cases, the thermal signature to be generated by thermal signature generating device <NUM> can be a pattern. Moreover, in some cases, control unit <NUM> can be configured and operable to generate the control signals to control the electric current through the at least one thermal radiation emitting element <NUM> in accordance with the pattern. In some cases, the pattern can be a pre-defined pattern.

In some cases, the thermal signature can be generated for marking one or more objects, e.g. in accordance with a pre-defined pattern. In some cases, due to the capability of the at least one thermal radiation emitting elements <NUM> to cool off rapidly, in accordance with the structure of the one or more thermal radiation emission devices <NUM> that include the at least one thermal radiation emitting elements <NUM>, as detailed further herein, inter alia with respect to <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG> and <FIG>, the at least one thermal radiation emitting elements <NUM> can be configured to alternate between conducting electrical current (i.e., being turned on) and not conducting electrical current (i.e., resting) at a high rate. This can enable the thermal signature generating device <NUM> to emit thermal radiation at a high pulse rate for marking the one or more objects. For example, in order to mark the one or more objects with a maximum energy efficiency, the at least one thermal radiation emitting element <NUM> can conduct electrical current for about one one-hundredth of a second at a temperature of about <NUM> and not conduct electrical current for about one second. It is to be noted that the thermal radiation emitting element <NUM> can be capable of cooling off from <NUM> in as little time as <NUM>/<NUM> of a second.

In some non-claimed cases, thermal signature generating device <NUM> can be configured to further include a thermographic camera (not shown in <FIG>) that is capable of determining a heatmap of an area of interest, and wherein the pattern (i.e., the thermal signature) is generated to match the heatmap. In some non-claimed cases, the pattern can be generated to match the heatmap in order to camouflage an object located between a viewer and the area of interest. In some non-claimed cases, at least one thermal radiation emitting element <NUM> can be heated continuously at a temperature between approximately <NUM> and <NUM> in order to camouflage an object.

Attention is now drawn to <FIG>, a schematic illustration of one example of components of a fuse-shaped housing <NUM> configured to hold thermal radiation emitting element <NUM>, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, the components of the fuse-shaped housing <NUM> can be configured to include (non-limiting): a first cap <NUM>, a second cap <NUM>, a first pair of heat sinks <NUM>, a second pair of heat sinks <NUM>, and a thermally transparent sleeve <NUM>.

In some cases, first cap <NUM> can be of a cylindrical shape and configured to seal the fuse-shaped housing <NUM> at a first longitudinal end thereof. In some cases, first cap <NUM> can also be configured to include a first electrical contact constituting a first electrode of electrical interface <NUM>, the first electrical contact and first electrode being manufactured from at least one electrically conductive material.

In some cases, second cap <NUM> can also be of a cylindrical shape and configured to seal the fuse-shaped housing <NUM> at a second longitudinal end thereof that is opposite the first longitudinal end of the fuse-shaped housing <NUM>. In some cases, second cap <NUM> can also be configured to include a second electrical contact constituting a second electrode of electrical interface <NUM>, the second electrical contact and second electrode being manufactured from at least one electrically conductive material.

The first pair of heat sinks <NUM> can be configured to include a first heat sink <NUM> and a second heat sink <NUM>. In some cases, as illustrated in <FIG>, the first heat sink <NUM> and the second heat sink <NUM> can each be shaped as a semicircle or as a semi-oval.

The second pair of heat sinks <NUM> can be configured to include a third heat sink <NUM> and a fourth heat sink <NUM>. In some cases, as illustrated in <FIG>, the third heat sink <NUM> and the fourth heat sink <NUM> can each be shaped as a semicircle or as a semi-oval.

Thermally transparent sleeve <NUM> can be a cylindrical sleeve. In some cases, the thermally transparent sleeve <NUM> can be made of one or more of the following materials: germanium, Teflon, silicon, zinc selenide or polyethylene.

Attention is now drawn to <FIG>, a schematic illustration of one example of thermal radiation emission device <NUM>, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, in some cases, thermal radiation emission device <NUM> can be configured to include thermal radiation emitting element <NUM> and a fuse-shaped housing <NUM>, the components of which are detailed earlier herein, inter alia with reference to <FIG>.

In some cases, the first cap <NUM> of the fuse-shaped housing <NUM> can be configured to include a first electrical contact and first electrode of electrical interface <NUM> that contacts thermal radiation emitting element <NUM> at a first end thereof.

In some cases, the second cap <NUM> of the fuse-shaped housing <NUM> can be configured to include a second electrical contact and second electrode of electrical interface <NUM> that contacts thermal radiation emitting element <NUM> at a second end thereof opposite the first end of thermal radiation emitting element <NUM>. That is, the thermal radiation emitting element <NUM>, e.g. including an array of CNTs, extends along a space between two spaced-apart opposite solid surfaces defined by two opposite electrodes. Upon application of a voltage across the first and second electrical contacts of electrical interface <NUM>, an electrical current can be made to flow through the first electrical contact, thermal radiation emitting element <NUM> and the second electrical contact (in this order, or in the opposite order), thereby causing thermal radiation emitting element <NUM> to emit thermal radiation for generating part or all of the thermal signature.

In some cases, as illustrated in <FIG>, the first pair of heat sinks <NUM> can be connected to the first cap <NUM>. Moreover, in some cases, as illustrated in <FIG>, part of thermal radiation emitting element <NUM> can be situated between the first heat sink <NUM> and the second heat sink <NUM> (shown in <FIG>).

In some cases, as illustrated in <FIG>, the second pair of heat sinks <NUM> can be connected to the second cap <NUM>. Moreover, in some cases, as illustrated in <FIG>, part of thermal radiation emitting element <NUM> can be situated between the third heat sink <NUM> and the fourth heat sink <NUM> (shown in <FIG>).

In some cases, as illustrated in <FIG>, a first longitudinal end of thermally transparent sleeve <NUM> can be connected to first cap <NUM>, and a second longitudinal end of thermally transparent sleeve <NUM>, opposite the first longitudinal end of thermally transparent sleeve <NUM>, can be connected to second cap <NUM>. In this manner, thermally transparent sleeve <NUM> can be configured to surround the components of thermal radiation emission device <NUM> that are situated longitudinally between the first cap <NUM> and the second cap <NUM>. It is to be noted that in some cases (not as illustrated in <FIG>), the first electrode and the second electrode of electrical interface <NUM> can extend along a length of the thermal radiation emitting element <NUM>. In some cases, as illustrated in <FIG>, thermally transparent sleeve <NUM> can be configured to surround the following components of thermal radiation emission device <NUM>: thermal radiation emitting element <NUM>, at least part of first heat sink <NUM>, at least part of second heat sink <NUM>, at least part of third heat sink <NUM>, and at least part of fourth heat sink <NUM>. By surrounding thermal radiation emitting element <NUM>, thermally transparent sleeve <NUM> can isolate thermal radiation emitting element <NUM> from the environment external to thermal radiation emission device <NUM>, and thereby protect thermal radiation emitting element <NUM> from being damaged. It is to be noted that according to the invention only the ends of the thermal radiation emitting element <NUM> contact a solid surface, such that a majority of a surface area of the thermal radiation emitting element <NUM> is not in contact with any solid surface.

In some cases, thermally transparent sleeve <NUM> can be configured to provide a vacuumed environment for thermal radiation emitting element <NUM>, thereby improving a durability of thermal radiation emitting element <NUM> and preventing structural failure of thermal radiation emitting element <NUM> relative to a thermal radiation emitting element <NUM> in a non-vacuumed environment.

In some cases, thermal radiation emitting element <NUM> can be configured to comprise an array of CNTs, the array being connected by its two opposite ends to the two opposite electrodes in first cap <NUM> and second cap <NUM>, respectively, and extending along a space between the electrodes.

In some cases, as illustrated in <FIG>, thermal radiation emitting element <NUM> can be configured to have a flat surface. In some cases in which thermal radiation emitting element <NUM> has a flat surface, fuse-shaped housing <NUM> can be configured to comprise a marking (not shown), for example a vertical mark along an external surface of first cap <NUM> or an external surface of second cap <NUM>, the marking instructing a user of the thermal signature generating device <NUM> of a connection direction of connecting fuse-shaped housing <NUM> to holder <NUM>. In this manner, thermal radiation emitting element <NUM> can be situated within thermal signature generation unit <NUM> at an orientation that enables thermal signature generation unit <NUM> to direct thermal radiation towards desired directions.

Attention is now drawn to <FIG>, a schematic illustration of one example of components of a holder <NUM> that is configured to hold thermal radiation emission device <NUM>, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, in some cases, and as illustrated in <FIG>, holder <NUM> can be configured as a fuse holder <NUM>, being a holder <NUM> that is capable of holding a fuse-shaped housing <NUM>, which is described earlier herein, inter alia with reference to <FIG>.

In some cases, as illustrated in <FIG>, fuse holder <NUM> can be configured to include a reflector <NUM> for directing the thermal radiation that is emitted by thermal radiation emitting element <NUM> towards desired directions.

In some cases, as illustrated in <FIG>, fuse holder <NUM> can be further configured to include a first mounting bracket <NUM> and a second mounting bracket <NUM>. Moreover, reflector <NUM> can be configured to be mounted on the first mounting bracket <NUM> and the second mounting bracket <NUM>, as detailed further herein, inter alia with reference to the present figure and <FIG>.

In some cases, as illustrated in <FIG>, fuse holder <NUM> can also be configured to include a mount <NUM>. Moreover, in some cases, reflector <NUM> can be configured to be mounted on the first mounting bracket <NUM>, the second mounting bracket <NUM> and the mount <NUM>, as detailed further herein, inter alia with reference to <FIG>.

In some cases, as illustrated in <FIG>, reflector <NUM> can be configured to have a planar section <NUM>, a first angled section <NUM> and a second angled section <NUM>. In some cases, as illustrated in <FIG>, the planar section <NUM> can be connected between the first angled section <NUM> and the second angled section <NUM>, such that each of the first angled section <NUM> and the second angled section <NUM> are connected to the planar section <NUM> at an obtuse angle with respect to the planar section <NUM>.

In some cases, as illustrated in <FIG>, reflector <NUM> can be configured to include a first continuous cut-out section <NUM> and a second continuous cut-out section <NUM>. Each of the first continuous cut-out section <NUM> and the second continuous cut-out section <NUM> can span part of the first angled section <NUM>, the planar section <NUM>, and part of the second angled section <NUM>, thereby enabling the reflector <NUM> to be mounted on the first mounting bracket <NUM> and the second mounting bracket <NUM>, as detailed further herein, inter alia with reference to <FIG>.

In some cases, as illustrated in <FIG>, first reflector mounting bracket <NUM> can be configured to include a first upright component <NUM>, a second upright component <NUM> and a first planar component <NUM>. Part of the first planar component <NUM> can be present between the first upright component <NUM> and the second upright component <NUM> (e.g., between a bottom end of the first upright component <NUM> and a bottom end of the second upright component <NUM>, as illustrated in <FIG>). The first upright component <NUM> and the second upright component <NUM> can be connected substantially perpendicularly to the first planar component <NUM> and opposite to one another along a first traversal planar axis 'y'.

In some cases, fuse holder <NUM> can be configured to provide electrical current to electrical interface <NUM> of fuse-shaped housing <NUM>. In some cases, at least part of the first reflector mounting bracket <NUM> can be electrically conductive, enabling providing an electrical current to electrical interface <NUM> of fuse-shaped housing <NUM> via first reflector mounting bracket <NUM>, e.g. based on control signals generated by control unit <NUM>.

Moreover, in some cases, as illustrated in <FIG>, second reflector mounting bracket <NUM> can be configured to include a third upright component <NUM>, a fourth upright component <NUM> and a second planar component <NUM>. Part of the second planar component <NUM> can be present between the third upright component <NUM> and the fourth upright component <NUM> (e.g., between a bottom end of the third upright component <NUM> and a bottom end of the fourth upright component <NUM>, as illustrated in <FIG>). The third upright component <NUM> and the fourth upright component <NUM> can be connected substantially perpendicularly to the second planar component <NUM> and opposite to one another along the first traversal planar axis 'y'.

In some cases, at least part of the second reflector mounting bracket <NUM> can be electrically conductive, enabling providing an electrical current to electrical interface <NUM> of fuse-shaped housing <NUM> via second reflector mounting bracket <NUM>, e.g. based on control signals generated by control unit <NUM>.

In some cases, mount <NUM> can be configured to enable the first reflector mounting bracket <NUM> and the second reflector mounting bracket <NUM> to be detachably connected thereto. Moreover, in some cases, mount <NUM> can be configured to enable part of reflector <NUM> to be mounted thereon, as discussed earlier herein, and as detailed further herein, inter alia with reference to <FIG>. The illustration of the mount <NUM> in <FIG> is provided for illustrative purposes only. The mount <NUM> can be manufactured in any manner that is consistent with the present disclosure.

Attention is now drawn to <FIG>, a schematic illustration of one example of a thermal signature generating device <NUM>, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, and as detailed earlier herein, inter alia with reference to <FIG>, in some cases, thermal signature generating device <NUM> can be configured to include thermal radiation emission device <NUM> and holder <NUM>, the thermal radiation emission device <NUM> being configured to include a housing <NUM> and a thermal radiation emitting element <NUM> (not illustrated in <FIG>) held by the housing <NUM>.

In some cases, as detailed earlier herein, inter alia with reference to <FIG>, and as illustrated in <FIG>, the housing <NUM> of the thermal radiation emission device <NUM> can be a fuse-shaped housing <NUM>.

In some cases, as detailed earlier herein, inter alia with reference to <FIG>, and as illustrated in <FIG>, holder <NUM> can be a fuse holder <NUM> that is capable of holding a fuse-shaped housing <NUM>.

In some cases, as detailed earlier herein, inter alia with reference to <FIG>, and as illustrated in <FIG>, fuse holder <NUM> can be configured to include a reflector <NUM>, first reflector mounting bracket <NUM>, second reflector mounting bracket <NUM>, and mount <NUM>. In some cases, as illustrated in <FIG>, each of first reflector mounting bracket <NUM> and second reflector mounting bracket <NUM> can be detachably connected to mount <NUM>. Moreover, in some cases, as illustrated in <FIG>, reflector <NUM> can be mounted on the following: first planar component <NUM> of first reflector mounting bracket <NUM>, first backstop <NUM> and second backstop <NUM> of mount <NUM>, and second planar component <NUM> of second reflector mounting bracket <NUM>. In addition, in some cases, as illustrated in <FIG>, reflector <NUM> can be mounted by lowering the first continuous cut-out section <NUM> (illustrated in <FIG>) of reflector <NUM> over first reflector mounting bracket <NUM> and lowering the second continuous cut-out section <NUM> (illustrated in <FIG>) of reflector <NUM> over second reflector mounting bracket <NUM>.

In some cases, as illustrated in <FIG>, fuse-shaped housing <NUM> can be detachably connected to the fuse holder <NUM>. Moreover, in some cases, as illustrated in <FIG>, fuse-shaped housing <NUM> can be detachably connected to the fuse holder <NUM> such that the fuse-shaped housing <NUM> is connected between first reflector mounting bracket <NUM> and second reflector mounting bracket <NUM>; a first longitudinal end of fuse-shaped housing <NUM> is positioned between first upright component <NUM> of first reflector mounting bracket <NUM> and second upright component <NUM> of first reflector mounting bracket <NUM>; and a second longitudinal end of fuse-shaped housing <NUM>, opposite the first longitudinal end of fuse-shaped housing <NUM>, is positioned between third upright component <NUM> of second reflector mounting bracket <NUM> and fourth upright component <NUM> of second reflector mounting bracket <NUM>.

In some cases, fuse-shaped housing <NUM> and fuse holder <NUM> can be configured to meet the DIN <NUM> standard.

In some cases, fuse holder <NUM> can be connected to a reflective surface (not shown) for reflecting the thermal radiation towards desired directions, as an alternative to the fuse holder <NUM> comprising a reflector <NUM>. Specifically, fuse holder <NUM> can be located within a substrate of the reflective surface, the substrate being designed to reflect thermal radiation towards the desired directions. Accordingly, upon connecting thermal radiation emission device <NUM> to the fuse holder <NUM>, the thermal radiation emission device <NUM> is located within the substrate of the reflective surface, resulting in the thermal radiation emitted by thermal radiation emission device <NUM> being reflected towards desired directions.

Attention is now drawn to <FIG>, schematic illustrations of one example of a front-end view and a back-end view, respectively, of a thermal radiation emission device <NUM> having a thermal radiation emitting element <NUM>, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, in some cases, thermal radiation emission device <NUM> can be configured to include a thermal radiation emitting element <NUM> that is attached to a housing <NUM>, being, for example, a printed circuit board (PCB). The thermal radiation emitting element <NUM> can be at an angle between <NUM>° and <NUM>° from vertical axis 'z'.

In some cases, the thermal radiation emitting element <NUM> can comprise an array of CNTs.

Thermal radiation emitting element <NUM> can extend between two spaced-apart opposite solid surfaces defined by two opposite electrodes <NUM>-a and <NUM>-b, respectively. The thermal radiation emitting element <NUM> can be connected by its two opposite ends to the two opposite electrodes <NUM>-a and <NUM>-b, respectively, and can extend along the space between the electrodes <NUM>-a and <NUM>-b, as illustrated in <FIG>. In some cases in which the thermal radiation emitting element <NUM> comprises an array of CNTs, the array of CNTs can be connected by its two opposite ends to the two opposite electrodes <NUM>-a and <NUM>-b, respectively, and can extend along the space between the electrodes <NUM>-a and <NUM>-b.

In some cases, as illustrated in <FIG>, a majority of a surface area of the thermal radiation emitting element <NUM> is not in contact with any solid surface.

In some cases, as illustrated in <FIG>, the thermal radiation emitting element <NUM> can be configured with an aspect ratio between cross-sectional dimensions of two surface regions of the two electrodes <NUM>-a and <NUM>-b on which the ends of the thermal radiation emitting element <NUM> are mounted and lengths of the thermal radiation emitting element <NUM> defined by the space between the electrodes <NUM>-a and <NUM>-b, the cross sectional dimension 'x' of each of the two surface regions being larger than the space 'y' between the electrodes <NUM>-a and <NUM>-b. In some cases in which the thermal radiation emitting element <NUM> comprises an array of CNTs, the array of CNTs can be configured with an aspect ratio between cross-sectional dimensions of the two surface regions of the two electrodes <NUM>-a and <NUM>-b on which the ends of the array are mounted and a length of the array defined by the space between the electrodes <NUM>-a and <NUM>-b, the cross sectional dimension 'x' of each of said two surface regions being larger than the space 'y' between the electrodes <NUM>-a and <NUM>-b.

Thermal radiation emission device <NUM> can be configured to include a first electrical connector <NUM>-a that connects to the electrode <NUM>-a, and a second electrical connector <NUM>-b that connects to the electrode <NUM>-b.

In some cases in which the thermal radiation emitting element <NUM> comprises an array of CNTs, the electrical current through the thermal radiation emitting element <NUM> can flow along a direction 'y' between the electrodes <NUM>-a and <NUM>-b in alignment with the lengths of fibers of the CNTs.

As illustrated in <FIG>, in some cases, the electrodes <NUM>-a and <NUM>-b can be configured to serve as heat sinks for removing heat generated by the thermal radiation emitting element <NUM>.

In some cases, in which the aspect ratio between cross sectional dimensions 'x' of each of the two surface regions of the electrodes <NUM>-a and <NUM>-b is larger than the space 'y' between the electrodes <NUM>-a and <NUM>-b, as illustrated in <FIG>, this aspect ratio enables the thermal radiation emitting element <NUM> to optimally use the electrical energy that it is provided for heating thermal radiation emitting element <NUM>, since it allows for a maximum surface area for the electrodes <NUM>-a and <NUM>-b while limiting energy loss. Moreover, thermal radiation emitting element <NUM> can be cooled off more quickly than if the space 'y' is greater than the cross sectional dimension 'x'. Additionally, the thermal radiation emitting element <NUM> illustrated in <FIG> can be cooled off more quickly since the space 'y' between the electrodes is not in contact with any solid uncooled surface. This aspect ratio ('x' > 'y') can also enable the at least one thermal radiation emitting element <NUM> to emit thermal radiation at a higher pulse rate than if the aspect ratio was such that the cross-sectional dimension 'x' is less than the space 'y'.

In some cases, thermal signature generating device <NUM> can be configured to include one thermal radiation emission device <NUM> having one thermal radiation emitting element <NUM>. In such cases, thermal radiation emission device <NUM> can be configured to include control unit <NUM>, configured and operable to generate control signals to control the electric current through the thermal radiation emitting element <NUM> in accordance with the thermal signature to be generated.

Alternatively, in some cases, thermal signature generating device <NUM> can be configured to include a plurality of thermal radiation emission devices <NUM> having a corresponding plurality of thermal radiation emitting elements <NUM>. In such cases, thermal signature generating device <NUM> can be configured to include the control unit <NUM>, configured and operable to generate control signals to control the electric current through the plurality of thermal radiation emitting elements <NUM> in accordance with the thermal signature to be generated.

Attention is now drawn to <FIG>, schematic illustrations of another example of a front-end view and a back-end view, respectively, of another thermal radiation emission device <NUM> having a thermal radiation emitting element <NUM>, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, in some cases, thermal radiation emission device <NUM> can be configured to include a thermal radiation emitting element <NUM> that is attached to a housing <NUM>, being, for example, a printed circuit board (PCB). In some cases, the housing <NUM> can be configured to include a male connector <NUM> enabling detachably connecting the thermal radiation emission device <NUM> to a female connector irrespective of an angle of rotation of the male connector <NUM> around an axis of the male connector <NUM> perpendicular to the female connector.

In some cases, the thermal radiation emitting element <NUM> can be configured to include an array of CNTs.

In some cases, as illustrated in <FIG>, the thermal radiation emitting element <NUM> can be configured with an aspect ratio between cross-sectional dimensions of two surface regions of the two electrodes <NUM>-a and <NUM>-b on which the ends of the thermal radiation emitting element <NUM> are mounted and a length of the thermal radiation emitting element <NUM> defined by the space between the electrodes <NUM>-a and <NUM>-b, the cross sectional dimension 'x' of each of the two surface regions being larger than the space 'y' between the electrodes <NUM>-a and <NUM>-b. In some cases in which the thermal radiation emitting element <NUM> comprises an array of CNTs, the array of CNTs can be configured with an aspect ratio between cross-sectional dimensions of the two surface regions of the two electrodes <NUM>-a and <NUM>-b on which the ends of the array are mounted and lengths of the array defined by the space between the electrodes <NUM>-a and <NUM>-b, the cross sectional dimension 'x' of each of the two surface regions being larger than the space 'y' between the electrodes <NUM>-a and <NUM>-b.

Moreover, in some cases in which the thermal radiation emitting element <NUM> comprises an array of CNTs, the electrical current through the thermal radiation emitting element <NUM> can flow along a direction 'y' between the electrodes <NUM>-a and <NUM>-b in alignment with the lengths of fibers of the CNTs.

In some cases, in which the aspect ratio between cross sectional dimensions 'x' of each of the two surface regions is larger than the space 'y' between the electrodes <NUM>-a and <NUM>-b, as illustrated in <FIG>, this aspect ratio enables the thermal radiation emitting element <NUM> to optimally use the electrical energy that it is provided for heating thermal radiation emitting element <NUM>, since it allows for a maximum surface area for the electrodes <NUM>-a and <NUM>-b while limiting energy loss. Moreover, thermal radiation emitting element <NUM> can be cooled off more quickly than if the space 'y' is greater than the cross sectional dimension 'x'. Additionally, the thermal radiation emitting element <NUM> illustrated in <FIG> can be cooled off more quickly since the space 'y' between the electrodes is not in contact with any solid uncooled surface. This aspect ratio ('x' > 'y') can also enable the at least one thermal radiation emitting element <NUM> to emit thermal radiation at a higher pulse rate than if the aspect ratio was such that the cross-sectional dimensions 'x' are less than the space 'y'.

Attention is now drawn to <FIG>, schematic illustrations of one example of a front-end view and a back-end view, respectively, of a thermal radiation emission device <NUM> having a series of thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d), in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, in some cases, thermal radiation emission device <NUM> can be configured to include a series of thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) and a housing <NUM>. Each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) can be connected between a respective two solid surfaces of the housing <NUM>, as detailed below. In some cases, housing <NUM> can be a printed circuit board (PCB).

Each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) can be configured to extend between two spaced-apart opposite solid surfaces defined by two opposite electrodes. To illustrate this, attention is drawn to <FIG>, which illustrates thermal radiation emitting element <NUM>-a extending between two spaced-apart opposite solid surfaces defined by two opposite electrodes <NUM>-a and <NUM>-b. As is illustrated in <FIG>, all remaining thermal radiation emitting elements (e.g., <NUM>-b, <NUM>-c, <NUM>-d) in the thermal radiation emission device <NUM> also extend between two spaced-apart opposite solid surfaces defined by two opposite electrodes, each electrode of the opposite electrodes being illustrated in <FIG> by two parallel and closely-spaced dashed lines.

As illustrated in <FIG>, each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) can be connected by its two opposite ends to its associated two opposite electrodes, respectively, and can extend along a space between the electrodes (e.g., being of a length 'y').

In some cases, each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) can comprise an array of CNTs, the array being connected by its two opposite ends to respective two opposite electrodes, respectively, and extending along a space between the electrodes (e.g., being of a length 'y').

In some cases, as illustrated in <FIG>, a majority of a surface area of each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) is not in contact with any solid surface.

In some cases, as illustrated in <FIG>, each thermal radiation emitting element (e.g., <NUM>-a) can be configured with an aspect ratio between cross-sectional dimensions of two surface regions of the two electrodes (e.g., <NUM>-a and <NUM>-b) on which the ends of the respective thermal radiation emitting element (e.g., <NUM>-a) is mounted and a length of the respective thermal radiation emitting element (e.g., <NUM>-a) defined by the space between the electrodes (e.g., <NUM>-a and <NUM>-b), the cross sectional dimension 'x' of each of said two surface regions being larger than the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b). In some cases in which each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) comprises an array of CNTs, the array of CNTs of each respective thermal radiation emitting element (e.g., <NUM>-a) can be configured with an aspect ratio between cross-sectional dimensions of the two surface regions of the two electrodes (e.g., <NUM>-a and <NUM>-b) on which the ends of the array are mounted and a length of the array defined by the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b), the cross sectional dimension 'x' of each of the two surface regions being larger than the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b).

Moreover, in some cases in which each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) comprises an array of CNTs, the electrical current through a respective thermal radiation emitting element (e.g., <NUM>-a) can flow along a direction 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b) to which the respective thermal radiation emitting element (e.g., <NUM>-a) is affixed, in alignment with the lengths of fibers of the CNTs.

As illustrated in <FIG>, in some cases, the electrodes (e.g., <NUM>-a and <NUM>-b) to which each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) is affixed can be configured to serve as heat sinks for removing heat generated by their associated thermal radiation emitting element (e.g., <NUM>-a).

In some cases, in which the aspect ratio for each thermal radiation emitting element (e.g., <NUM>-a) between cross sectional dimensions 'x' of each of the two surface regions of the electrodes (e.g., <NUM>-a and <NUM>-b) is larger than the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b), as illustrated in <FIG>, each thermal radiation emitting element (e.g., <NUM>-a) can optimally use the electrical energy that it is provided for heating the respective thermal radiation emitting element (e.g., <NUM>-a), since it allows for a maximum surface area for the electrodes (e.g., <NUM>-a and <NUM>-b) while limiting energy loss. Moreover, each thermal radiation emitting element (e.g., <NUM>-a) can be cooled off more quickly than if the space 'y' is greater than the cross sectional dimension 'x'. The space 'y' being less than the cross sectional dimension 'x' for each thermal radiation emitting element (e.g., <NUM>-a) is made possible by providing a thermal radiation emission device <NUM> that include a series of thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d), each thermal radiation emitting element of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) extending between two spaced-apart opposite solid surfaces defined by two opposite electrodes, instead of providing a thermal radiation emission device <NUM> that includes one large thermal radiation emitting element. Moreover, the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) can be cooled off more quickly since the space 'y' between the electrodes associated with each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) is not in contact with any solid uncooled surface. In addition, by providing an aspect ratio for each thermal radiation emitting element (e.g., <NUM>-a) between cross sectional dimensions 'x' of each of the two surface regions of the electrodes (e.g., <NUM>-a and <NUM>-b) that is larger than the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b), the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) can emit thermal radiation at a higher pulse rate than if the aspect ratio was such that the cross-sectional dimensions 'x' are less than the space 'y'.

As illustrated in <FIG>, the two opposite electrodes that are connected to each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) can be connected to respective electrical connections. For example, in the illustration of <FIG>, a front-end of the housing <NUM> includes electrical connections <NUM>, <NUM>, <NUM> and <NUM>. Moreover, in the illustration of <FIG>, a back-end of the housing <NUM> includes electrical connections <NUM>, <NUM>, <NUM> and <NUM>. The opposite electrodes of thermal radiation emitting element <NUM>-a are connected to electrical connections <NUM> and <NUM>, respectively; the opposite electrodes of thermal radiation emitting element <NUM>-b are connected to electrical connections <NUM> and <NUM>, respectively; the opposite electrodes of thermal radiation emitting element <NUM>-c are connected to electrical connections <NUM> and <NUM>, respectively; and the opposite electrodes of thermal radiation emitting element <NUM>-d are connected to electrical connections <NUM> and <NUM>, respectively.

Control unit <NUM> (not illustrated in <FIG>) can be configured and operable to generate control signals to control the electrical current through each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d), in accordance with the thermal signature to be generated.

Attention is now drawn to <FIG> and <FIG>, schematic illustrations of one example of a front-end view and a back-end view, respectively, of a thermal radiation emission device <NUM> having a plurality of thermal radiation emitting elements <NUM> in a disk configuration, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, in some cases, thermal radiation emission device <NUM> can be configured to include a plurality of thermal radiation emitting elements <NUM>, wherein at least one thermal radiation emitting element (e.g., <NUM>-a) of the thermal radiation emitting elements <NUM> faces a first direction and is operable to emit first thermal radiation in the first direction, and at least another thermal radiation emitting element (e.g., <NUM>-e) of the thermal radiation emitting elements <NUM> faces a second direction, other than the first direction, and is operable to emit second thermal radiation in the second direction.

An example of such a thermal radiation emission device <NUM> is illustrated in <FIG> and <FIG>. In the illustrations of <FIG> and <FIG>, thermal radiation emission device <NUM> includes a housing <NUM> having a disk configuration, the housing <NUM> including three sides (e.g., <NUM>-a, <NUM>-b, <NUM>-c). Each side of the sides (e.g., <NUM>-a, <NUM>-b, <NUM>-c) includes a plurality of thermal radiation emitting elements <NUM> that face a given direction, wherein the thermal radiation emitting elements <NUM> that are housed in each side of the sides (e.g., <NUM>-a, <NUM>-b, <NUM>-c) face a different direction than the thermal radiation emitting elements <NUM> that are housed in other sides of the sides (e.g., <NUM>-a, <NUM>-b, <NUM>-c). In the illustrations of <FIG> and <FIG>, a first side <NUM>-a of the housing <NUM> includes thermal radiation emitting elements <NUM>-a, <NUM>-b, <NUM>-c and <NUM>-d that face a first direction and are operable to emit thermal radiation in the first direction. Moreover, a second side <NUM>-b of the housing <NUM> includes thermal radiation emitting elements <NUM>-e, <NUM>-f, <NUM>-g and <NUM>-h that face a second direction, other than the first direction, and are operable to emit thermal radiation in the second direction. In addition, a third side <NUM>-c of the housing <NUM> includes thermal radiation emitting elements <NUM>-i, <NUM>-j, <NUM>-k and <NUM>-l that face a third direction, other than the first direction and the second direction, and are operable to emit thermal radiation in the third direction.

Each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) can be connected between a respective two solid surfaces of the housing <NUM>, as detailed below. In some cases, housing <NUM> can be a printed circuit board (PCB).

Each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) can extend between two spaced-apart opposite solid surfaces defined by two opposite electrodes, as detailed earlier herein, inter alia with reference to <FIG>.

Moreover, each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) can be connected by its two opposite ends to its associated two opposite electrodes, respectively, and can extend along a space between the electrodes (e.g., being of a length 'y').

In some cases, each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) can comprise an array of CNTs, the array being connected by its two opposite ends to respective two opposite electrodes, respectively, and extending along a space between the electrodes (e.g., being of a length 'y').

In some cases, as illustrated in <FIG> and <FIG>, a majority of a surface area of each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) is not in contact with any solid surface.

In some cases, as illustrated in <FIG>, each thermal radiation emitting element (e.g., <NUM>-d) can be configured with an aspect ratio between cross-sectional dimensions of two surface regions of the two electrodes (e.g., <NUM>-a and <NUM>-b) on which the ends of the respective thermal radiation emitting element (e.g., <NUM>-d) is mounted and a length of the respective thermal radiation emitting element (e.g., <NUM>-d) defined by the space between the electrodes (e.g., <NUM>-a and <NUM>-b), the cross sectional dimension 'x' of each of said two surface regions being larger than the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b). In some cases in which each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) comprises an array of CNTs, the array of CNTs of each respective thermal radiation emitting element (e.g., <NUM>-d) can be configured with an aspect ratio between cross-sectional dimensions of the two surface regions of the two electrodes (e.g., <NUM>-a and <NUM>-b) on which the ends of the array are mounted and a length of the array defined by the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b), the cross sectional dimension 'x' of each of the two surface regions 'x' being larger than the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b).

Moreover, in some cases in which each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) comprises an array of CNTs, the electrical current through a respective thermal radiation emitting element (e.g., <NUM>-d) can flow along a direction 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b) to which the respective thermal radiation emitting element (e.g., <NUM>-d) is affixed, in alignment with the lengths of fibers of the CNTs.

As illustrated in <FIG>, in some cases, the electrodes (e.g., <NUM>-a and <NUM>-b) to which each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) is affixed can be configured to serve as heat sinks for removing heat generated by their associated thermal radiation emitting element (e.g., <NUM>-d).

In some cases, in which the aspect ratio for each thermal radiation emitting element (e.g., <NUM>-a) between cross sectional dimensions 'x' of each of the two surface regions of the electrodes (e.g., <NUM>-a and <NUM>-b) is larger than the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b), each thermal radiation emitting element (e.g., <NUM>-d) can optimally use the electrical energy that it is provided for heating the respective thermal radiation emitting element (e.g., <NUM>-d), since it allows for a maximum surface area for the electrodes (e.g., <NUM>-a and <NUM>-b) while limiting energy loss. Moreover, each thermal radiation emitting element (e.g., <NUM>-d) can be cooled off more quickly than if the space 'y' is greater than the cross sectional dimension 'x'. The space 'y' being less than the cross sectional dimension 'x' for each thermal radiation emitting element (e.g., <NUM>-a) is made possible by providing a thermal radiation emission device <NUM> that include a plurality of series of thermal radiation emitting elements (e.g., series of thermal radiation emitting elements <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d), each thermal radiation emitting element of the thermal radiation emitting elements in each series (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d) extending between two spaced-apart opposite solid surfaces defined by two opposite electrodes, instead of providing a thermal radiation emission device <NUM> that includes one large thermal radiation emitting element at each side of the housing <NUM> have the disk configuration. Moreover, the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) can be cooled off more quickly since the space 'y' between the electrodes associated with each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) is not in contact with any solid uncooled surface. In addition, by providing an aspect ratio for each thermal radiation emitting element (e.g., <NUM>-a) between cross sectional dimensions 'x' of each of the two surface regions of the electrodes (e.g., <NUM>-a and <NUM>-b) that is larger than the space 'y' between the electrodes (e.g., <NUM>-a and <NUM>-b), the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) can emit thermal radiation at a higher pulse rate than if the aspect ratio was such that the cross-sectional dimensions 'x' are less than the space 'y'.

The two opposite electrodes that are connected to each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l) can be connected to respective electrical connections (not shown in <FIG> and <FIG>).

Control unit <NUM> (not illustrated in <FIG> and <FIG>) can be configured and operable to generate control signals to control the electrical current through each of the thermal radiation emitting elements (e.g., <NUM>-a, <NUM>-b, <NUM>-c, <NUM>-d, <NUM>-e, <NUM>-f, <NUM>-g, <NUM>-h, <NUM>-i, <NUM>-j, <NUM>-k, <NUM>-l), in accordance with the thermal signature to be generated.

Attention is now drawn to <FIG>, a flowchart illustrating an example of a method <NUM> for generating a thermal signature, in accordance with the presently disclosed subject matter.

In accordance with the presently disclosed subject matter, two opposite electrodes of an electrical interface <NUM> of housing <NUM> can be configured to provide electrical current through at least one thermal radiation emitting element <NUM>, causing the at least one thermal radiation emitting element <NUM> to emit thermal radiation for generating the thermal signature, wherein each of the at least one thermal radiation emitting elements <NUM> extends between two spaced-apart opposite solid surfaces defined by two opposite electrodes and comprises an array of Carbon Nanotubes (CNTs), the array being connected by its two opposite ends to said two opposite electrodes, respectively, and extending along a space between the electrodes, the electrodes providing the electrical current through the thermal radiation emitting element <NUM> (block <NUM>).

It is to be noted that, with reference to <FIG>, the block can be broken down to a few blocks and/or other blocks may be added. Furthermore, whilst the flowchart is described also with reference to the system elements that realizes them, this is by no means binding, and the block can be performed by elements other than those described herein.

Claim 1:
A thermal signature generating device (<NUM>), the device (<NUM>) comprising:
at least one thermal radiation emitting element (<NUM>), each of the at least one thermal radiation emitting elements (<NUM>): (i) extending between two spaced-apart opposite solid surfaces defined by two opposite electrodes (<NUM>-a, <NUM>-b, <NUM>-a, <NUM>-b, <NUM>-a, <NUM>-b), wherein only opposite ends of the thermal radiation emitting element (<NUM>) each contact one of said opposite solid surfaces, and (ii) comprising an array of Carbon Nanotubes (CNTs), the array being connected by its two opposite ends to said two opposite electrodes (<NUM>-a, <NUM>-b, <NUM>-a, <NUM>-b, <NUM>-a, <NUM>-b), respectively, and extending along a space between the electrodes (<NUM>-a, <NUM>-b, <NUM>-a, <NUM>-b, <NUM>-a, <NUM>-b), the electrodes providing electrical current through the thermal radiation emitting element (<NUM>), causing the thermal radiation emitting element (<NUM>) to emit thermal radiation for generating the thermal signature.