FR2916527A1 - Screening device for e.g. military vehicle, has optical elements with light receiver and light remitter with light input and output sides along respective solid angles, where receiver and transposer are connected together by transmitter - Google Patents

Abstract

The device has optical elements with a light receiver (1) whose light input side is along a solid angle (3), and a light transposer whose light output side is along another solid angle (7). The receiver and the transposer are connected together by a transmitter. The transmitters are made from optical fiber strands (11) and the receivers are constituted by one of ends of the strands and terminated by a plane section. The receivers have an elliptical or spherical bulge (9) forming the transposer.

Description

SCREEN DEVICE FOR CAMOUFLAGE

  The present invention relates to the realization of a screen device capable of capturing light from its immediate environment and re-emitting it so that this device is seen as having the appearance of its environment, thereby achieving effective camouflage. A preferred embodiment of the invention uses light receiving and re-emitting elements implanted in a textile or in a rigid panel. These elements are preferably formed by short sections of optical fiber shaped and whose juxtaposition will form a kind of fur. Said optical fiber elements are arranged in such a way that they absorb the incident light and reemit it relatively randomly. This device, of great longevity and practically unalterable, is intended to make light camouflaged combat uniforms and canvases or tarpaulins for military vehicles. The combat suits and tarpaulins of the prior art generally comprise to ensure the concealment of more or less complex patterns but frozen on increasingly sophisticated textiles. The present invention deviates resolutely from these techniques because it constitutes an optical camouflage system that adapts to the environment in real time. It operates according to a passive process of capturing and reflecting light from the image of the surrounding medium. The image reflected by the device then has the hues of the environment and blends in this environment to constitute an ideal camouflage. This device can be made in flexible or rigid form depending on the support used to receive the optical fiber elements. The present invention provides a decisive advantage to its wearer by diverting the visual perception of a human observer or an observation system and leading to an erroneous interpretation of his perception and this day and night, with or without without a light amplification system or infrared vision.

  The invention is equally applicable to individualized camouflage suits or panels for men, vehicles, installations and to new type of insulating textiles. The invention therefore relates to a screen device for camouflage characterized in that it comprises, inserted into a support, optical elements composed of at least a receiver and a light emitter. Embodiments of the invention will be described hereinafter by way of non-limiting examples with reference to the accompanying drawings, in which: FIG. 1 is a schematic diagram of a light receiving and retransmitting element According to the invention, FIG. 2 is a schematic view of a preferred embodiment of an optical element according to the invention. FIGS. 3 and 4 show two variants of the embodiment of the optical element of FIG. FIGS. 5 and 6 show two other variants of the embodiment of the optical element of FIG. 2; FIG. 7 is a view of the optical element of FIG. 2 partially implanted in a fabric frame seen in section, FIGS. 8 and 9 are side views of 3 optical elements of FIG. 2 completely implanted in a tissue frame. FIGS. 10a and 10b are two flat views, inside and outside, of part of the screen according to the invention. 30 showing a first FIGS. 11a and 11b are two plan views, inside and outside, of a part of the screen according to the invention showing a second embodiment of the juxtaposition of the optical elements of FIG. FIGS. 12a and 12b are two plan views, inside and outside, of part of the screen according to the invention showing a third embodiment of the juxtaposition of the optical elements of FIG. 2. FIGS. 13a and 13b are two views flat, inside and outside, of a part of the screen according to the invention showing a fourth embodiment of the juxtaposition of the optical elements of Figure 2. Figure 14 is a flat, external view of a variant of the embodiment of FIG. 12b using optical elements of FIG. 6.

  Figure 15 is a plan view of a variant of the embodiment of a support of the device according to the invention using a flexible sheet material. FIG. 16 is a plan view, external, of a variant of the embodiment of FIG. 15, using a variant of the embodiment of FIG. 13.

  A screen device according to the invention consists of a juxtaposition of optical elements schematically comprising each, as shown in FIG. 1, a light receiver 1 having an input surface 2 and a solid angle of light input 3, also called input cone, said input cone having an axis 54, a light transmitter 4, a light re-transmitter 5 having an output surface 6 and a solid output angle of the light 7 , also called output cone, said output cone having an axis 55, the light transmitter 4 connecting the receiver 1 to the retransmitter 5.

  In the case of the preferred embodiments of the invention where the light receiver 1, the transmitter 4 and the retransmitter 5 are made of transparent optical materials, the optical element operates in both directions and the light can also enter through the surface. 6 of the re-transmitter and out through the surface 2 of the receiver.

  The materials constituting the receiver, the transmitter and the repeater are capable of absorbing part of the light received giving the element an absorption coefficient K generally close to 1 but which can be adjusted by a judicious choice of said materials. depending on the final characteristics sought for the screen device.

  The shapes of the plane, concave or convex input and output surfaces 6, as well as those of the receivers and the retransmitters can be chosen to obtain solid angles of entry 3 and exit 7 of the light adapted to the final characteristics. searched for the screen device.

  As shown in FIG. 2, an optical element of one of the preferred embodiments of the invention consists of a strand of optical fiber 8 forming the transmitter 4 and the length of which will be fixed according to the characteristics to be obtained, typically one to four centimeters and having, at one of its ends, a bulge 9, substantially spherical or having the shape of an ellipsoid, forming the retransmitter 5, the other end of said fiber, remained smooth, being terminated by a section substantially flat straight line 10 forming the receiver 1 of the fiber 8. This section can obviously be perpendicular to said fiber 8 or inclined with respect to this fiber. The surface of the section 10 may also be convex or concave as shown in Figures 3 and 4 or take any other form to change the solid input angle of the light.

  The optical fiber used to make the strands is chosen so as to pass the spectrum of visible light, for example from 400 to 800 nm. Its outside diameter will preferably be less than 300 microns.

  The bulge can be obtained by various means and in particular by localized reflow of the fiber at its end. As shown in FIG. 2, the characteristics of the fiber for the entry and exit of the light are different. The entry (or exit) of the light through the face 35 2 is made according to a relatively small aperture angle of aperture 3 if said face is flat and which can be enlarged or decreased depending on whether this face is made convex or concave. In the same way, the exit (or entry) of the light through the bulge 9 is by a cone whose vertex angle 7 will depend on the diameter and the ellipticity of said bulge with respect to the diameter of the core. the fiber.

  To increase the quantity of light received, it is advantageous to use optical elements whose reception surface of the receiver 1 and the solid input angle 3 of the light are increased as shown in FIG. , the light receiver is formed by a bulge having substantially the shape of a cone 52 terminated by a flat or curved face 2 depending on the desired solid angle.

  In the same way, the spherical or ellipsoidal bulge 9 forming the retransmitter may also be replaced by a cone 53 terminated by a flat or curved face 6, FIG.

  Depending on the desired characteristics, the receivers 1 situated at one end of the fiber optic strands may also take the spherical or ellipsoidal shape proposed for the retransmitters 5, and conversely, the retransmiters may take the smooth form with a flat section or curve.

  The fiber itself may be composed of a core of index n1 and a cladding of index n2 with n2> n1 or made of gradient index material. Any other type of optical fiber may also be used.

  The material of the fiber may also be selected depending on the particular mechanical, thermal or other characteristics required of the screen device.

  Thus, the optical fiber strands are incorporated in a support so as to constitute a kind of fur. In a preferred embodiment, this support is a simple fabric web consisting of flexible threads that intersect and the fiber optic strands are installed so that the light receiving portion 1 and the bulge 9 forming the retransmitter 5 lie on the same side of said fabric frame. For this purpose, each fiber strand is threaded, FIG. 7, by its smooth end, through a weft of fabric consisting of weft threads 12 and 13 parallel to the plane of the figure and of weft threads, 14 and 15, substantially perpendicular to the plane of said figure, a strand 11 passing for example in a mesh formed by the weft son 12, 13, 14 and 15. Said fiber strand entering the weft mesh on the side which will be the outer side of the device screen.

  The strand 11 is then folded and re-threaded by its end 19, FIG. 8 in a second stitch, between two weft threads 16 and 17, for example, stitch located at a distance such that, once the finished set, the radius of curvature of the fiber is not less than the limit radius of the fiber, radius below which the optical losses of said fiber become too large. In FIG. 8, two other fiber strands are shown by way of example, one strand 20 entering behind the weft yarn 13 and between two weft yarns 14 and 22 and one strand 21 entering behind another weft yarn, parallel the plane of the figure but not shown because hidden by the weft yarn 12, and between two weft son 22 and 16 and then out through another mesh between two weft son 23 and 24. As the strands are installed and that the weft is filled, it is tightened and the smooth strands are pulled outwards so that the bulges are close to the weft and that said strands are well held by said weft, the bulges serving both stop nodes and light scattering systems. The positioning of the strands is done in such a way that the maximum and preferably all the stitches of the weft are filled, either by a bulge end 9 or by a smooth strand 19, by distributing the bulges and the strands. smooth on the surface of the frame. The angle to be made by the input axis 54 of the receiving portion 1 of the fiber strands relative to the plane of the weft is preferably less than 45. The angle to be made by the fiber portion 18 which carries the bulge 9, with respect to the plane of the weft, is preferably greater than 45 or even better, as shown in FIG. 9, as close as possible to 90 mm. so that the output axis of the light 55 is substantially perpendicular to said plane of the frame.

  In this FIG. 9, the screen is placed vertically and the smooth ends 19 of the fiber strands, forming a light receiver 1, are oriented downwards and thus receive by their solid input angles 3 of axis 54 the light which comes from of the ground. The bulges 9, because of the orientation substantially perpendicular to the weft of the fiber portions 18 which carry them, return the light transmitted by the fiber in solid angles 7 whose axis 55 is substantially horizontal. Thus, the bulges 9 are seen from a distance with a shade corresponding to that of the ground which illuminated the receivers 1 and thus constitute a camouflaging element that adapts effectively to the environment.

  To obtain a maximum filling of the frame by the optical elements or fiber strands, many arrangements of said optical elements are possible. Figures 10 to 13 show the principle of four preferred embodiments of the arrangement of optical elements made in the form of the fiber strands of Figure 2 in a fabric frame.

  In the first embodiment and as shown in FIG. 10a, which shows the internal part of the camouflage device, the optical elements are arranged in chevrons on a frame composed of vertical wires 31 to 39 and horizontal wires 25 to 30. A first strand of fiber 40 enters the frame by a mesh formed of two horizontal son 25 and 26 and two vertical son 31 and 32. Said first strand outwards by a staggered mesh two columns to the right and two rows below, mesh formed of two horizontal yarns 27 and 28 and two vertical yarns 33 and 34. A second yarn 41 enters the weft with a mesh located three columns to the left and on the same row as the input mesh of the first strand 40, formed of four son 25, 26, 34 and 35, and out of a mesh located two columns to the left and two rows below the point of entry, mesh formed of four other son 27, 28, 32 and 33 passing through- above the first strand 40. A third strand 42 enters the weft by a mesh located below the mesh of entry of the first strand 40, mesh formed of four other son 26, 27, 31 and 32, and leaves by a mesh located below the output mesh of said first strand 40, mesh formed of four other son 28, 29, 33 and 34, passing over the second strand 41 and so on.

  Figure 10b shows the outer part of the device where the bulges 9 are aligned vertically and separated by the smooth portions 19 of the fiber strands oriented downwards, to the left or to the right. For clarity of the drawing, these smooth strands are represented very short but it is obvious that they can have any length depending on the desired effect.

  For the second embodiment of the device according to the invention, FIG. 11a, the optical elements are grouped by four. A first strand 44 enters by a stitch, 25, 26, 31, 32 and out of a mesh 27, 28, 32, 33 shifted one row to the right and two rows below. A second strand 45 enters by a mesh just to the right of the mesh of entry of the first strand 44, mesh 25, 26, 32, 33 and leaves by a mesh located to the left of the point of exit of this first strand 44, mesh 27, 28, 31, 32, passing over said first strand 44. A third strand 46 enters by a mesh below the input mesh of the first strand 44, mesh 26, 27, 31, 32, and spring by a mesh 28, 29, 32, 33, located below the output mesh of said first strand 44, passing over the second strand 45. A fourth strand 47 enters by a mesh located below the stitch d input of the second strand 45, mesh 26, 27, 32, 33, and spring by a mesh 28, 29, 31, 32, located below the output mesh of said strand 45, passing over the first strand 44 and the second strand 46.

  Figure 11b shows the outer portion of the device where the bulges 9 are grouped in double rows alternating with double rows of smooth portions 19 of the fiber strands 44 to 47 facing downwards.

  For the third embodiment, FIG. 12a, the fiber strands are placed parallel to one another and inclined relative to the weft. The entry points of the strands are placed on the same column, between two son 32 and 33 for example, and the exit points are placed on the immediately adjacent column, between the son 31 and 32 for example and staggered at least two rows.

  Viewed from the outside, FIG. 12b, the bulges 9 are aligned in columns separated by the smooth strands 19.

  Finally, for the fourth embodiment, FIG. 13a, the fiber strands are placed alternately at 45 relative to the field wires or parallel to a main direction of the frame, the middle of each strand covering a point of entry or exit. exit of the previous strand. A first strand 48 enters through a mesh 25, 26, 31, 32 and leaves by a mesh 27, 28, 33, 34 located two rows lower and two columns to the right for example. A second strand 49 enters by a stitch 26, 27, 33, 34 located above the point of exit of the strand 49 and leaves two rows lower on the same column by a stitch 28, 29, 33, 34. A third strand 50 enters by a mesh 27, 28, 32, 33 located to the right of the exit point of the first strand 48 and leaves by a mesh 29, 30, 34, 35 located two rows lower and two columns further to the right. being parallel to said strand 48. A fourth strand 51 enters by a mesh 28, 29, 34, 35 located to the right of the point of exit of the second strand 49 and leaves two stitches lower, being parallel to said second strand 49 and so on.

  Seen from the outside, Figure 13b, the receivers constituted by the bulges 9 are grouped vertically two by two and alternate with the receivers constituted by the smooth strands, also grouped vertically two by two. These receivers are oriented alternately down and to the left in this embodiment.

  The fabric frame can be made in any type of material. It can in particular be made itself fiber optic. The color of the frame will preferably be neutral, for example a gray of RGB components 149.149.149. The same screen device can combine by zones, preferably random, several of the weaving modes described above to vary the effects produced.

  Thus produced, the screen device according to the invention operates as follows. The smooth strands 19, which are all outside, are downwardly facing the floor at an angle that depends on the weave and is generally less than 60. These smooth strands 19 capture the light coming from the ground and send it back to the bulges 9 which reemit it in their solid angles whose axes are close to the horizontal plane. All of these bulges are therefore seen from afar as having the color of the ground at the location where the wearer is. In the case where several types of weaving are used on one and the same screen, each of the weaving zones may take on a particular hue depending on the orientation of its receiving strands 19. All the types of weaving described above and their possible variants can use any of the optical elements from those of FIGS. 2 to 6 or any variant that could be made of them.

  FIG. 14 shows, for example, the outside face of the device of FIG. 12 corresponding to the third weaving mode described above and produced with the optical sensors of FIG. 6.

  To achieve the screen device according to the invention, it is possible to replace the fabric frame by any other support capable of holding in place the optical elements of the device. In a variant of the invention, FIG. 15, the support of the optical elements consists of a sheet of a material 56 which is preferably flexible and which is pierced with holes 57 arranged in substantially perpendicular lines and columns, so that that the optical elements can be installed in a manner similar to that used for the weaves of Figures 8 to 11.

  The holes 57 can also be arranged in substantially equilateral triangles and thus form lines 58, 59 and 60 which intersect at 60, Figure 16. In this type of drilling, variants of the previously described weaves can be easily implanted. In said Figure 16, a weave derived from that of Figure 13 is shown. On this weave, each fiber strand 61 is introduced by alternately making an angle of + or - 30 with respect to a weaving axis 62 and covering the exit point of the fiber strand previously introduced.

  In another variant, the support may be made of a nonwoven material during the manufacture of which the optical elements are inserted in a suitable position. The support may also be made by molding a material which may be rigid, preferably flexible, a resin for example, material in which the optical elements will be included, or by any other means for placing the optical elements. in such a position that they can receive the light from their environment and send it back to deceive an observer.

Claims (12)

  1. A screen device for camouflage characterized in that it comprises, inserted in a support, optical elements 5 each composed of at least one receiver and a light emitter.   2. A camouflage screen device according to claim 1 characterized in that the optical elements comprise a light receiver (1) having a light input face (2) at a solid angle (3) and a retransmitter light source (5) having a light-emitting exit face (6) at a solid angle (7), said light receiver and light-emitter being preferably interconnected by a transmitter (4). 15   3. Screening device for camouflage according to claim 2 characterized in that the transmitters (4) are made from strands of optical fiber (8) and in that the receptors (1) are constituted by one end of the 20 strands optical fiber (8) left smooth and terminated by a substantially flat section (10) and which can also take any other form.   4. Screening device for camouflage according to one of claims 1 or 2 characterized in that the emitters (5) are constituted by bulges (9) substantially spherical and which can also be elliptical.   5. Screening device for camouflage according to one of claims 2 or 3 characterized in that the receivers (1) consist of substantially conical bulges (9) (52) terminated by an inlet face (2) substantially flat but which can also be curved. 35   6. Camouflage screen device according to the preceding claims, characterized in that the emitters and the light receivers of the optical elements are each produced according to any one of the forms proposed for receivers, flat-face smooth (10). ), with spherical bulges (9), with conical bulges (53).   7. Screening device for camouflage according to one of the preceding claims characterized in that the optical elements are incorporated in a flexible support, preferably a frame of flexible son (12, 13, 14, 15) which intersect forming meshes in which optical fiber strands (11) constituting optical elements are threaded.   8. Screening device for camouflage according to one of the preceding claims, characterized in that the light receivers (1) are preferably oriented downwards, so that they receive light from their close environment and that the light re-emitters (5) are oriented substantially horizontally so that they send light to distant areas.   9. Screening device for camouflage according to one of the preceding claims characterized in that the optical elements are arranged in chevrons on a frame composed of vertical son (31 to 39) and horizontal son (25 to 30), a first fiber strand (40) entering the weft by a mesh formed of two horizontal son (25 and 26) and two vertical son (31 and 32), said first strand emerging outwardly by a staggered stitch of two columns to straight and two rows below, formed of two horizontal son (27 and 28) and two vertical son (33 and 34), a second strand (41) entering the frame by a mesh located three columns to the left and on the same rank as the input mesh of the first strand (40), formed of four son (25, 26, 34 and 35), and emerging by a mesh located two columns to the left and two rows below the point of entry, formed of four other threads (27, 28, 32 and 33) passing over the first strand (40), a third strand (42) entering the weft by a stitch located below the first strand (40) input mesh, formed of four further strands (26, 27, 31 and 32), and emerging by a mesh located below the output mesh of said first strand (40), formed of four further yarns (28, 29, 33 and 34), passing over the second strand (41) and so subsequently, the light emitters formed for example by bulges (9) being aligned vertically and separated by the receivers formed for example by the smooth portions (19) of the fiber strands oriented downwards and alternatively to the left and to the right .   10. Screening device for camouflage according to one of claims 1 to 8 characterized in that the optical elements are grouped by four, a first strand (44) entering by a mesh, 25, 26, 31, 32) and emerging by a stitch (27, 28, 32, 33) shifted one row to the right and two rows below, a second strand (45) returning by a stitch just to the right of the stitch of the first strand ( 44), stitch (25, 26, 32, 33) and emerging from a stitch to the left of the exit point of the first strand (44), stitch (27, 28, 31, 32), passing over said strand (44), a third strand (46) returning through a mesh located below the mesh of entry of the first strand (44), mesh (26, 27, 31, 32), and emerging by a mesh (28, 29). , 32, 33), located below the output mesh of said first strand (44), passing over the second strand (45), a fourth strand (47) returning through a mesh located below the stitch (d). entry of the two th strand (45), mesh (26, 27, 32, 33), and emerging by a mesh (28, 29, 31, 32) located below the output mesh of said strand (45), passing over the first strand (44) and the second strand (46) are light emitters consisting of bulges (9) being arranged in double rows alternating with double rows of receivers formed by the smooth portions (19) of the fiber strands (44). 47) facing downwards.   11. Screening device for camouflage according to one of claims 1 to 8 characterized in that the fiber strands are placed parallel to each other and inclined relative to the frame, the entry points of the strands being placed on the same column, between two son (32 and 33) for example, and the exit points being placed on the immediately adjacent column, between the son (31 and 32) for example and shifted by at least two rows, the receptors formed by the bulges 9 being aligned in columns separated by the receivers formed by the smooth strands (19).   12. camouflage screen device according to one of claims 1 to 8 characterized in that the fiber strands are placed alternately at 45 relative to the frame son or parallel to a main direction of the frame, the middle of each strand covering an entry or exit point of the preceding strand, a first strand (48) entering through a stitch (25, 26, 31, 32) and emerging by a stitch (27, 28, 33, 34) located in two rows lower and two columns to the right for example, a second strand (49) returning by a mesh (26, 27, 33, 34) located above the point of exit of the strand (49) and emerging two rows lower on the same column by a mesh (28, 29, 33, 34), a third strand 50 entering by a mesh (27, 28, 32, 33) located to the right of the exit point of the first strand (48) and emerging by a mesh (29, 30, 34, 35) located two rows lower and two columns further to the right parallel to said strand (48), a fourth strand (5) 1) entering through a mesh (28, 29, 34, 35) located to the right of the second strand exit point (49) and emerging two meshes lower parallel to said second strand (49) and so on.