Night-vision scope with improved display

Abstract

The invention relates to a night-vision scope (10), comprising: - a camera lens (SL) and a light intensifier device (ILD) comprising a screen (E) on which a so-called amplified image (Iamp) is displayed; - a first optical system (OS1) for transporting and inverting an image, comprising at least one lens, having an optical axis (OA) and configured to produce a curved so-called intermediate image (Iint) of the amplified image, the curved intermediate image being located on a curved image surface (SIC); - a first transparent display (TD1) having an annular peripheral zone (ZPA) arranged in the vicinity of the curved image surface and configured to display information, said information overlapping the intermediate image; - an eyepiece (EP) configured to form a rectified image of the intermediate image, the first optical system and the eyepiece forming the overall optical system of the scope.

Description

DESCRIPTION TITLE: Enhanced Display Night Vision Goggle FIELD OF THE INVENTION

[0001] The present invention relates to the field of night vision goggles (or binoculars) comprising a light intensifier. More specifically, the subject of the invention relates to the display of additional data to the user of the goggles. STATE OF THE ART

[0002] Most night vision goggles rely on light-intensifying technology to provide environmental awareness that supports movement and threat detection in the dark.

[0003] Traditionally, a night vision goggle comprises a lens, a light intensification device that forms an intensified image from the image coming from the lens, and an observation eyepiece. The light intensification device comprises a photocathode that transforms the photons in the image coming from the lens into electrons, a microchannel plate that electronically amplifies these electrons, and a phosphorescent screen that transforms the amplified electrons into photons, the electrons having been accelerated between the microchannel plate and the phosphorescent screen. There are different types of photocathode. Examples include GaAs or multi-alkaline photocathodes. There are also different types of phosphors. P22 or P43 type phosphors emit in the green, P45 type phosphors emit in the white.

[0004] The magnification of night vision goggles (worn on the user's head) is usually unitary, and weapon-mounted scopes for shooting can have magnifications of up to 10.

[0005] The amplified image is observed through an eyepiece. Typically, the field of view has a diameter of around 40 degrees. Its standard focal length is 27 mm, identical to that of the objective. The eye relief is 25 mm.

[0006] If the telescope had only these elements, the image would be seen inverted by the observer. The telescope therefore necessarily includes an optical device allowing the image from the lens to be inverted. There are different types.

[0007] A first type of inverting device consists of using an inverting tube in which a block of inverting fiber is placed at the tube outlet instead of a glass window. The block is then integrated into the tube. The diagram of a telescope of this type is shown in Figure 1. This telescope comprises, in this order, the shooting objective 1, the light intensification device 2 and the eyepiece 4. The light intensification device 2 comprises the photocathode 21 which receives the image from the objective 1, the microchannel plate 22, the phosphorescent screen 23 and a network of inverting fibers 31. The phosphorescent screen is placed at the input of the network of fibers. The observer is symbolized by an eye Y. The object O and its different images through the device are represented by oriented arrows. The path of the light rays is shown in thin lines. Currently, it is possible to have blocks of optical fibers with high resolution.In practice, inverting fiber blocks present a certain number of defects intrinsic to their manufacturing technology and introduce artifacts into the image, thus reducing the intrinsic performance of the intensifier tubes: significant misalignment between the input and output of the intensifier tube, inducing various parallelism defects; loss of MTF ("Modulation Transfer Function") and contrast; losses and defects in luminance uniformity, requiring the eyepiece to be sized in order to exploit rays whose emission indicator diverges from the optical axis of the eyepiece and therefore enlarge the diameters of the eyepiece lenses; increased weight of the telescope.

[0008] A second type of solution for inverting the image is to introduce image transport between the screen and the eyepiece itself. This solution has many advantages, provided that the perceived image is of good quality. As we have seen, the fields of the objectives and eyepieces of night vision goggles are generally large, of the order of 40 degrees. It is therefore essential to maintain good image quality throughout the field. Optical aberration is likely to significantly degrade the quality of this image. is the distortion which increases, as a first approximation, as a function of the third power of the field. Document FR3082318 describes an optical architecture of a telescope illustrated in Figure 2 (lens 1 not shown) making it possible to optimize the optical combination of the inverter device / eyepiece assembly while allowing a distortion aberration compatible with a given resolution at the edge of the field to remain.

[0009] The telescope comprises a light intensifier device, an inverting device 51 / 52 and an eyepiece 53 / 54, the light intensifier device comprising an imager 23. The inverting device is image transport. It comprises a first field optical group 51 arranged in front of the imager mainly configured to correct field aberrations (distortion, astigmatism) and a second aperture optical group 52, forming an inverted intermediate image 11 of the imager I0. The eyepiece comprises a third optical group 53 arranged in the vicinity of this intermediate image and a fourth optical group 54, forming from this intermediate image a corrected image collimated at infinity, visible to the observer Y. The complete optical system of the telescope thus comprises four optical groups 51 / 52 / 53 / 54.At least two diopters of the first optical group 51 or of the third optical group 53 and one diopter of the second optical group 52 comprise aspherical surfaces calculated so as to obtain a distortion of the rectified image compatible with the resolution of the light intensifier device.

[0010] To determine aspherical surfaces, the calculation process involves the following two steps: - calculation of the two third-order and fifth-order distortion coefficients of the rectified image as a function of the radius of the object field, the angular radius of the image field, the paraxial focal length and the tolerated edge-of-field resolution; - optimization of the aspherization coefficients of at least two diopters distributed between the first optical group and the third optical group and one diopter of the second optical group so that the calculated distortion of the rectified image corresponds to the tolerated distortion defined by the two distortion coefficients previously calculated.

[0011] The miniaturization of uncooled thermal imaging cameras offers the possibility of integrating them into night vision goggles. To do this, an image from the thermal imaging camera is superimposed on the intensified image displayed on a display. The combination of light-intensified imaging and thermal imaging through optical fusion provides significantly superior performance for combatant missions in threat detection. Thermal imaging, which is energy-intensive, is used to remove doubts during critical phases of a mission. Light-intensified imaging, which is low-energy, is used throughout a mission to improve mobility in a night environment.

[0012] A schematic of the principle of combining the intensified image from an ILO intensifier tube and an infrared image displayed by a DispO display with a CombO optical combiner is shown in Figure 3. An image of the ILO intensifier screen is formed at infinity towards the user (eyepiece) by the GL20 / GL10 assembly, and an image of the DispO display is formed at infinity towards the user (eyepiece) by the GL30 / GL10 assembly. The CombO combiner is arranged inside the optical combination of the GL20 / GL10 and GL23 / GL10 assemblies and performs the superposition of the two images. These two superimposed images are re-imaged by the eyepiece towards the user.

[0013] An example of such a combination adapted to the telescope of Figure 2 is illustrated in Figure 4 (shooting objective not shown). The architecture of the optical system of the telescope of Figure 3 is well suited to the integration of an optical splitter allowing the injection of an additional optical path which is seen by the user. Indeed, the absence of a block of inverting fibers at the output of the intensifier tube makes it possible to exploit the rays whose emission indicator converges with respect to the optical axis and therefore to minimize the diameter and the optical length of the splitter compared to conventional solutions.

[0014] The optical system of the telescope comprises an additional optical path comprising an optical separator 58 arranged between the first optical group 51 and the second optical group 52, a fifth optical group 55 and a display 57. The group 55 is functionally equivalent to the group 51. An intermediate image of the display 57 is produced by the assembly 55 / 52. This path additional is symbolized by a double arrow. In the case of Figure 4, the optical separator 58 is a separator cube comprising a semi-reflecting surface. It would be possible to replace it with a simple semi-reflecting blade. The image of the display 57 is merged with the image of the imager 23. The user Y therefore sees, superimposed, an intensified image from the light intensifier device and the image of the display from IR vision.

[0015] It is possible, while maintaining this architecture, to add a second additional channel as seen in Figure 4 by using the unused channel of the optical separator 58. This second additional channel is symbolized by a triple arrow. In Figure 4, this second channel comprises a sixth optical group 56 and a matrix of photodetectors 59. It is thus possible to record the image from the light intensifier device.

[0016] To improve the infantryman's perception of the environment, the display of geographical position, orientation and tactical data is essential. For ergonomic reasons, the display of tactical data should preferably be carried out at the periphery of the visual field to maintain a clear and unobstructed view of the immediate environment.

[0017] Thermal imaging and tactical data are displayed by display 57 (e.g., an OLED microdisplay) in the example of Figure 3 and optically mixed with splitter cube 58 with the light-intensified path.

[0018] This poses two significant technical problems, because to display data at the edge of the field, it is necessary to increase the geometric dimensions of the OLED screen and the splitter cube. This results in an increase in mass, cost, and a reduction in the autonomy of the night vision binoculars. In most cases, the designers of these devices limit the field of view of the display to values ​​below 40° and it is then impossible to display tactical data at the periphery of the intensified image.

[0019] Figure 5 illustrates this configuration corresponding to an image perceived by the ENVG-B binocular from L3Harris, which combines a light-intensified binocular and a thermal camera with an optical combiner. The field of view of the light intensification is 40° circular (circle 40). and the field of the thermal camera and tactical information is symbolized by the rectangle 41. The field of the screen displaying the IR image is estimated at 30°. The tactical information 42 is then displayed in the middle of the circle 40 and not on its periphery.

[0020] Another disadvantage of this configuration is that displaying tactical data requires the implementation of complex electronics and a high-resolution, power-hungry OLED display. Therefore, it is not possible to display only tactical data in a low-power manner.

[0021] Another way of superimposing the images from the intensifier and the IR camera is described in document WO03 / 105084 according to an illustrated architecture. The lens 34 images a scene 20 on a light intensifier 14 comprising a photocathode 36, a microchannel plate 38, a phosphor screen 40, which emits an image 10. A block of optical fibers 42 transports the image 10 and a transparent screen 28 is arranged at the output of the block of fibers. This screen 28, transparent and emitting light, is connected to a thermal camera 16 via the electronics 58 (connected to a battery 60). The screen 28 displays the image 12 detected by the camera (lens 48 which images the scene 24 identical to the scene 22 with a slightly offset optical axis). Downstream of the screen 28 we therefore have the combined image 54 (10+12) which is imaged in the eye 55 of the user U by an eyepiece 50.

[0022] This device has the same drawbacks as before. The screen 28 must be large if we want to display tactical data on the periphery, and must be able to display IR images with good resolution (high-resolution pixelated screen) at a video rate. Note that a transparent screen capable of achieving such performance does not currently exist. The binoculars described in this document also have all the drawbacks linked to the use of a fiber optic pad mentioned above.

[0023] An aim of the present invention is to remedy the aforementioned drawbacks by proposing a night vision scope allowing low-power tactical data to be displayed on the periphery of the intensified image field. DESCRIPTION OF THE INVENTION

[0024] The present invention relates to a night vision goggle comprising: - a shooting lens (SL) and a light intensifying device comprising a screen on which an image called an amplified image is displayed, - a first optical image transport and inversion system comprising at least one lens, having an optical axis and configured to produce a so-called curved intermediate image of said amplified image, said curved intermediate image being located on a curved image surface, - a first transparent display having an annular peripheral zone arranged in the vicinity of said curved image surface and configured to display information, said information being superimposed on the intermediate image, - an eyepiece configured to form a rectified image of said intermediate image, the first optical system and the eyepiece forming the overall optical system of the telescope.

[0025] According to one embodiment, the first display comprises a plurality of independently addressed patterns for displaying the information.

[0026] According to one embodiment, the first display is monochrome.

[0027] According to another embodiment, the first display is configured to display information having at least two different colors.

[0028] According to one embodiment, the first display is flat and the information is present only in said annular peripheral zone.

[0029] According to another embodiment, the first display is flexible and has a shape which fits the curved image surface.

[0030] According to one embodiment, the first display has a dimension greater than a dimension of the intermediate image, at least part of said information being located in a part of the peripheral zone of the first display outside the field of the intermediate image.

[0031] According to one embodiment, the overall optical system comprises an optical path comprising an optical combiner, a second optical system and a second display configured so that an image from the second display is confused with the intermediate image.

[0032] According to one embodiment, the first optical system comprises a first field optical group arranged in front of the first display and a second aperture optical group forming said intermediate image, and the eyepiece comprises a third optical group arranged in the vicinity of said intermediate image and a fourth optical group.

[0033] According to one embodiment, the overall optical system comprises an optical path comprising an optical combiner arranged between the first optical group and the second optical group, a second optical system and a second display, the image of the second display produced by the second optical system, the optical combiner and the second optical group being merged with said intermediate image.

[0034] According to one embodiment, the bezel further comprises a third transparent display having a central area arranged in the vicinity of said curved image surface and configured to display information.

[0035] The following description presents several exemplary embodiments of the device of the invention: these examples are not limiting of the scope of the invention. These exemplary embodiments present both the essential characteristics of the invention as well as additional characteristics linked to the embodiments considered.

[0036] The invention will be better understood and other characteristics, aims and advantages thereof will appear during the detailed description which follows and with reference to the appended drawings given as non-limiting examples and in which:

[0037] Figure 1 already cited illustrates a telescope according to the state of the art with a first type of reversing device consisting of placing a block of reversing optical fibers against the phosphorescent screen.

[0038] Figure 2 already cited illustrates a telescope according to the state of the art with a second type of reversing device comprising an image transport between the screen and the eyepiece.

[0039] Figure 3 already cited illustrates an optical combination of an image from a screen of a light intensification device with an image from a thermal camera.

[0040] Figure 4 already cited illustrates a telescope according to Figure 2 comprising an additional channel comprising an optical separator and a display, and a second channel comprising a matrix of photo detectors.

[0041] Figure 5 already cited illustrates an image perceived by binoculars according to the state of the art which combine a light-intensifying binocular and a thermal camera with an optical combiner.

[0042] Figure 6 already cited illustrates another example of binoculars according to the state of the art carrying out an optical intensifier / thermal imaging combination, in which a block of optical fibers transports the image from a phosphorescent screen and which includes a transparent screen arranged at the output of the block of fibers.

[0043] Figure 7 illustrates an embodiment of a telescope 10 according to the invention.

[0044] Figure 8 illustrates another embodiment of a telescope 10 according to the invention.

[0045] Figure 9 illustrates the case where the display covers a field larger than that of the intermediate image, at least part of the information being located in the area of ​​the display outside the intermediate image.

[0046] Figure 10 illustrates the case where the annular peripheral display area of ​​TD1 is located completely outside the intermediate image.

[0047] Figure 11 illustrates a bezel 10 according to the invention based on the bezel architecture described in Figure 2.

[0048] Figure 12 illustrates a telescope according to the invention integrating a combination with an IR image as described in Figure 4.

[0049] Figure 13 illustrates an embodiment in which the display TD1 is planar and the bezel according to the invention further comprises a third planar transparent display which has a central zone arranged in the vicinity of the curved image surface SIC and configured to display information. DETAILED DESCRIPTION OF THE INVENTION

[0050] The idea of ​​the invention is to display tactical information, typically but not limited to symbols, numbers, etc., with a dedicated transparent screen associated with a suitable optical system.

[0051] The telescope 10 according to the invention is illustrated in Figure 7. It comprises a shooting objective SL configured to form an image of a scene Sc at the input of a light intensifier device ILD. It also comprises a light intensifier device ILD comprising a screen E on which is displayed an image called a lamp amplified image. The screen E is typically a phosphor screen. The telescope 10 also comprises a first optical system OS1 for image transport and inversion comprising at least one lens and which has an optical axis OA. This system is therefore not a block of optical fibers. The optical system OS1 is configured to produce a so-called intermediate curved lint image of the amplified image, which is located on a curved image surface SIC. In other words, the image plane of the optical system OS1 has a curvature. The lint image is therefore in focus on this surface SIC.The PC plane tangent to SIC and perpendicular to OA is shown in Figure 7. The central part of the intermediate image is located in the vicinity of PC. As lint is curved the peripheral part of lint is located around a plane called the annular image plane of lint, which is located at a different location on the optical axis than PC.

[0052] To produce a curved image, the OS1 optical system therefore has a field curvature that is not fully corrected, unlike a conventional imaging system. The curvature can be concave (as illustrated in Figure 7) or convex depending on the characteristics of OS1.

[0053] The bezel 10 also comprises a first transparent display TD1, which has an annular peripheral zone ZPA arranged in the vicinity of the curved image surface SIC and which is configured to display information. The display TD1 is integrated in the optical path where the intermediate image is formed. The information displayed on TD1 is superimposed on the intermediate image lint at the periphery. The intermediate image augmented with the information displayed by TD1 is called an enriched intermediate image. information displayed by TD1 is thus located in the vicinity of or in the area in which the periphery of the intermediate image is in focus. The TD1 display cuts the peripheral part of the SIC surface for the case of a flat TD1 screen, or follows the peripheral part or even the entirety of SIC for the case of a curved TD1 screen (see below).

[0054] As this TD1 display is dedicated to the display of simple information, for example of the symbol type, it preferably has a low resolution, with passive or direct addressing. According to one embodiment the screen is pixelated and according to another preferred embodiment the screen comprises a plurality of PAT patterns addressed independently to display said information.

[0055] The screen is transparent and emits light (emissive screen). For example, the emissive patterns are designed with an inorganic electroluminescent material deposited on a glass or plastic substrate. According to one embodiment, the patterns can be of different colors.

[0056] The telescope also comprises an eyepiece EP configured to form a rectified image of the intermediate image. The first optical system OS1 and the eyepiece EP form the overall optical system of the telescope 10 according to the invention. The eyepiece EP is configured to correct the curvature introduced by the optical system OS1, and more generally, it is sought to compensate by the eyepiece for the aberrations introduced by OS1, so that the user sees at infinity a clear image at all points of the screen E and peripheral information.

[0057] Preferably, the first optical system OS1 is configured for annular optimization (i.e. on its periphery) of the intermediate image. Indeed, the information displayed by TD1 and superimposed on this directory part of lint must appear clear to the user. Thus, only the peripheral part of the intermediate image must be of good optical quality.

[0058] Creating a curved image is optically easier than creating a flat image, and the design of the OS1 system is therefore simplified, resulting in a less complex and lighter system. In addition, it is also optically simpler to send a curved image to infinity rather than than a plane image, and the optical design of the eyepiece is also simplified, certain constraints of the EP eyepiece being lifted compared to a conventional eyepiece. In addition, as explained above, the eyepiece must be optimized only at the edge of the field and not at the center of the intermediate image, which makes it possible to reduce the dimensions of the eyepiece and thus to lighten its weight. Thus, the use of a curved intermediate image, i.e. not optimized in the plane, makes it possible to reduce the dimensions and the mass of the night vision scope / binoculars according to the invention.

[0059] The telescope 10 according to the invention makes it possible to display information on the periphery, or even outside the intermediate image (i.e. outside the field of the intermediate image). The displayed information being arranged in the vicinity of SIC, it is in the right position to be imaged by the eyepiece while appearing clear to the user.

[0060] The use of a low-power screen allows the display of symbology while maintaining the autonomy of the scope.

[0061] The scope according to the invention allows for a wide field of view. In fact, the information displayed by TD1 can extend beyond the lint frame, unlike the example of the binoculars illustrated in Figure 5 in which the field of the OLED display screen is included in the field of the light intensifier screen.

[0062] According to one embodiment, the screen is planar (flat) and arranged in a plane PD, as illustrated in Figure 7. The plane PD intersects the SIC surface at the periphery of the field. Only the annular peripheral zone of TD1 comprises patterns to be displayed; its central part is not used. Indeed, information displayed in this central part of TD1 would be seen blurred by the user. For the case of a concave intermediate image, the planar display TD1 is arranged upstream of the plane PC, and for the convex case, the display TD1 is arranged downstream of the plane PC.

[0063] According to another embodiment of the bezel 10 according to the invention illustrated in Figure 8, the display TD1 is flexible and has a shape which fits the SIC surface. In this case the entire display can be used for displaying information. For example, an electroluminescent material is deposited on a curved substrate, made of glass or plastic. In this case, a reticle can be displayed in the center of the TD1 screen, which is clear to the user.

[0064] The display can of course be square in size, what matters is that an annular peripheral area of ​​the screen is arranged in the vicinity of the SIC surface.

[0065] According to one embodiment, the first display TD1 is monochrome, which promotes annular optimization of the intermediate image by the first optical system OS1.

[0066] According to another embodiment, the display TD1 is configured to display information having at least two different colors. For example, different types of information can thus receive different color coding.

[0067] The display TD1 can cover a field larger than that of the lint image. Thus, according to one embodiment, the first display TD1 has a dimension larger than the dimension of the intermediate image (typically a diameter or a diagonal), at least part of the information being located in the area of ​​the first display outside the intermediate image (outside the lint field). This case is illustrated in Figure 9. The display TD1 has a diameter larger than the lint diameter. Symbols materialized by PAT patterns are displayed on TD1 in a crown (ZPA), one part of which is opposite the peripheral zone 80 of lint and the other part is outside it.

[0068] The annular peripheral display zone ZPA of TD1 can also be located completely outside the intermediate image, as illustrated in figure 10. In this case the PD plane intersects the SIC surface in a SIC zone adjacent to that on which lint is located (see figure on the right). Zone 70 in the PD plane corresponds to an area where the intermediate image is slightly defocused. The numbers are displayed using segment-shaped patterns. Such a configuration makes it possible not to obscure any point of the scene displayed on the screen E.

[0069] An example of a design of a telescope according to the invention is an intermediate image of diameter 16 mm, and a display TD1 of diameter 18 mm. The distance Pt between the plane PC and the plane PE (edge ​​of TD1 corresponding to the end of ZPA) is 6 mm. The curvature of the intermediate image, measured by the distance Pim between the PC and PP planes (end of the intermediate image), is 5 mm. This lint curvature corresponds to a radius of curvature of 9 mm.

[0070] It has been established that taking into account the dimensions of the screen E and the parameters of OS1 and EP typical of a telescope, preferably the desired radius of curvature of the lint image is between 8 and 30 mm.

[0071] The telescope 10 according to the invention is compatible with a telescope architecture described in document FR3082318 and illustrated in figure 2. Such a telescope according to the invention is illustrated in figure 11 (lens SL not shown). The first optical system OS1 comprises a first optical group GO1 of field arranged in front of the first display and a second optical group GO2 of aperture forming the intermediate image lint symbolized by an arrow, and the eyepiece EP comprises a third optical group GO3 arranged in the vicinity of the intermediate image and a fourth optical group GO4 forming the rectified image of this intermediate image. The different groups of lenses are here configured to have a distortion as described in document FR3082318 (see above), and the groups GO1 / GO2 of the first optical system OS1 are further configured to generate a curved image surface according to the invention.In this non-limiting example, the display TD1 is flat and arranged downstream of the plane PC, between the plane PC and the first lens of the group GO3, corresponding to the case of a convex curvature of lint.

[0072] Of course, the invention is compatible with less specific systems (OS1, EP) allowing image transport according to the invention.

[0073] According to one embodiment, the enhanced intermediate image is combined with an image from a second display Disp connected to a camera, typically a thermal camera. The overall optical system of the telescope comprises an optical path comprising an optical combiner, a second optical system and a second display configured so that an image from the second display I2 is merged with the intermediate image. The display Disp is typically a high-resolution matrix display (for example 1280x1024) capable of operating at the video rate, for example a micro OLED display.

[0074] The combination is carried out, for example, according to the diagram in Figure 3.

[0075] An example of such a combination is illustrated in Figure 9, the rectangle 81 corresponding to the image I2 which is not in focus in the plane of the display TD1.

[0076] This hybrid solution with two displays TD1 and Disp (in addition to the E screen of the intensifier tube) combines the best of two technologies: Micro-Oled technology allows to display the video image of a camera or a mapping system with excellent resolution and infinite graphic possibilities, the transparent screen technology (passive or direct addressing, with much fewer pixels or segments) allows to display symbols with reduced consumption.

[0077] The telescope according to the invention integrating the combination with an IR image is compatible with the telescope architecture described in document FR3082318 and figure 4, and is illustrated in figure 12 (lens SL not shown). The overall optical system of the telescope 10 comprises an optical path comprising an optical combiner Comb arranged between the first optical group GO1 and the second optical group GO, a second optical system OS2 and a second display Disp. This additional path is symbolized by a double arrow. The combiner Comb is for example a splitter cube comprising a semi-reflecting plate, or a simple optical plate. The image of Disp given by the second optical system OS2, the combiner and the second group OG2 is merged with the curved intermediate image of the screen of the light intensifier device symbolized by an arrow.In the non-limiting example of figure 12 the image surface is convex and the flat display TD1 is arranged downstream of the plane PC.

[0078] According to an illustrated embodiment the display TD1 and plan and the bezel 10 according to the invention further comprises a third transparent display TD2 plan which has a central zone arranged in the vicinity of the curved image surface SIC and configured to display information. As the lint image is curved, the central zone of the display TD2, arranged in the vicinity of SIC around the optical axis OA, i.e. in the vicinity of PC, is at a position on the optical axis different from that of the first display TD1. The display TD2 allows the display of information in the central part of the image intermediate. In this case the optical system OS1 must also be optimized over the entire field of the intermediate image. According to one embodiment the information displayed is a reticle. According to another embodiment the information displayed corresponds to the IR image.

[0079] According to one embodiment, the telescope according to the invention is a pair of binoculars. In this case, there is one IL / OS1 / EP channel per eye. There can be a transparent display on each channel, displaying different information, or only on one channel. The binoculars can be stereo binoculars.

[0080] For example, the glasses according to the invention can be: - an HHTI (Hand-Held Thermal Imager) observation scope, these binoculars sometimes being equipped with a zoom and presenting a magnification of 1 to 10. - a sensor vision shooting scope.

Claims

CLAIMS 1. Night vision goggle (10) comprising: - a shooting lens (SL) and a light intensifying device (ILD) comprising a screen (E) on which an image called an amplified image (lamp) is displayed, - a first optical system (OS1) for image transport and inversion comprising at least one lens, having an optical axis (OA) and configured to produce a so-called intermediate (lint) curved image of said amplified image, said intermediate curved image being located on a curved image surface (SIC), - a first transparent display (TD1) having an annular peripheral zone (ZPA) arranged in the vicinity of said curved image surface and configured to display information, said information being superimposed on the intermediate image, - an eyepiece (EP) configured to form a rectified image of said intermediate image, the first optical system and the eyepiece forming the overall optical system of the telescope.

2. Glasses according to the preceding claim in which the first display comprises a plurality of patterns (PAT) addressed independently to display said information.

3. Glasses according to one of the preceding claims in which the first display is monochrome.

4. Glasses according to one of claims 1 or 2 wherein the first display is configured to display information having at least two different colors.

5. Glasses according to one of the preceding claims in which the first display is flat and said information is present only in said annular peripheral zone.

6. Glasses according to one of claims 1 to 4 in which the first display is flexible and has a shape which fits the curved image surface.

7. Glasses according to one of the preceding claims in which the first display has a dimension greater than a dimension of the intermediate image, at least part of said information being located in a part of the peripheral zone of the first display outside the field of the intermediate image.

8. Glasses according to one of the preceding claims in which the overall optical system comprises an optical path comprising an optical combiner (Comb), a second optical system (SO2) and a second display (Disp) configured so that an image of the second display (I2) is merged with the intermediate image.

9. Glasses according to one of the preceding claims in which the first optical system (OS1) comprises a first optical group (GO1) of field arranged in front of the first display and a second optical group (GO2) of aperture forming said intermediate image, and in which the eyepiece comprises a third optical group (GO3) arranged in the vicinity of said intermediate image and a fourth optical group (GO4).

10. Glasses according to the preceding claim in which the overall optical system comprises an optical path comprising an optical combiner (Comb) arranged between the first optical group and the second optical group, a second optical system (OS2) and a second display (Disp), the image of the second display produced by the second optical system, the optical combiner and the second optical group being merged with said intermediate image.

11. Glasses according to one of the preceding claims further comprising a third transparent display (TD2) having a central zone (ZC) arranged in the vicinity of said curved image surface and configured to display information.

Images