Optical sighting system with fusion of optical channels in distinct spectral bands without parallax

Abstract

The present invention relates to an optical sighting system (10), which comprises: - a splitting unit (20) capable of spectrally splitting an incident optical signal (FI) into a first optical signal (F1) and a second optical signal (F2); - a first optical channel (22) for conveying the first optical signal (F1); - a second optical channel (24) for capturing the second optical signal (F2); - an image capture and processing unit (26) capable of generating an image, referred to as a captured image, from the second optical signal (F2) captured by the second optical channel (24); and - a unit (28) for generating an image, referred to as a fused image, resulting from the fusion of a rendering of the captured image and an image from the first optical signal (F1) conveyed by the first optical channel (22).

Description

[0001] DESCRIPTION

[0002] TITLE: Optical vision system with fusion of optical paths in distinct spectral bands without parallax

[0003] The present invention relates to an optical aiming system. The present invention also relates to an assembly comprising a firing system and such an optical aiming system.

[0004] This invention falls within the field of firearm sighting instruments, for both civilian and military applications, such as rifles. It particularly addresses the application of optical fusion sighting systems that combine a direct optical path with an infrared path.

[0005] Modern optical and infrared fusion reflex viewfinders have two image capture channels: an infrared channel and a visible channel. These capture channels are spatially offset from each other, resulting in parallax (the two viewing axes being offset from each other).

[0006] In concrete terms, for a target at a finite distance and close, the two infrared images and direct optical vision will be spatially offset at the time of restitution in the case where the parallax related to the spacing of the channels is corrected at long distance.

[0007] When this parallax is corrected to have a short-distance superposition, there will then be a shift for objects located at a long distance.

[0008] There is therefore a need for an optical aiming system that can fuse optical paths in distinct spectral bands, including infrared and direct visible path, while overcoming parallax problems.

[0009] To this end, the invention relates to an optical aiming system comprising:

[0010] - a separation unit capable of spectrally separating an incident optical flux into a first optical flux and a second optical flux, the first optical flux being in a first band of wavelengths, the second optical flux being in a second band of wavelengths,

[0011] - a first optical path for the transmission of the first optical flow,

[0012] - a second optical channel for capturing the second optical flux,

[0013] - an image capture and processing unit capable of generating an image, called the captured image, from the second optical stream captured by the second optical channel, and - an image generation unit, called the fused image, the fused image being viewable by a user of the optical viewing system and resulting from the fusion of a rendering of the captured image and an image from the first optical stream conveyed by the first optical channel.

[0014] According to other advantageous aspects of the invention, the optical sighting system comprises one or more of the following features, taken individually or in all technically possible combinations:

[0015] - The separation unit includes:

[0016] - a subset for separating the incident optical flux into the first optical flux and the second optical flux, and

[0017] - a reflective subset capable of reflecting one of the first optical flux and the second optical flux so that the first optical flux and the second optical flux propagate in substantially parallel directions;

[0018] - the separation subset includes a separating blade or a separating cube;

[0019] - the separation subset includes a central zone suitable for reflecting an optical flux in one of the first and second wavelength bands and a peripheral zone suitable for transmitting an optical flux in the other of the first and second wavelength bands, making it possible to obtain the first optical flux and the second optical flux;

[0020] - the central zone is formed by a mirror reflecting in the first or second band of wavelengths;

[0021] - the reflective subset is formed of a mirror reflecting in the first or second band of wavelengths;

[0022] - the first band of wavelengths is between 380 nanometers and 780 nanometers, the second band of wavelengths being between 380 nanometers and 5 millimeters, preferably between 780 nanometers and 5 millimeters, advantageously between 3 micrometers and 5 millimeters;

[0023] - The generation unit includes:

[0024] - a display specifically designed to show the image captured by the second optical channel,

[0025] - a combining optics of the optical flux from the captured image displayed on the screen with the first optical flux conveyed by the first optical path to obtain a combined optical flux, and

[0026] - an eyepiece to form the fused image from the combined optical flow; - the generation unit includes:

[0027] - an additional image capture and processing unit capable of generating an image, called an additional image, based on the first optical flow transmitted through the first optical path, and

[0028] - a display capable of forming the fused image based on the image captured from the second optical channel and the additional image.

[0029] The invention also relates to an assembly comprising:

[0030] - a firing system, and

[0031] - an optical aiming system as described above.

[0032] The invention will become clearer upon reading the following description, given solely by way of non-limiting example, and made with reference to the drawings in which: [Fig. 1] Figure 1 is a schematic view of an example of an optical aiming system, the optical aiming system comprising a separation unit, a first optical channel, a second optical channel, an image capture and processing unit, and a unit for generating a fused image,

[0033] [Fig. 2] Figure 2 is a schematic view of an example of a first embodiment of the separation unit of the optical sighting system of Figure 1,

[0034] [Fig. 3] Figure 3 is a schematic view of an example of a second embodiment of the separation unit of the optical sighting system of Figure 1,

[0035] [Fig. 4] Figure 4 is a schematic view of an example of a portion of the optical sighting system, the unit for generating a fused image being, according to a first example embodiment, and

[0036] [Fig. 5] Figure 5 is a schematic view of another example of a portion of the optical sighting system, the unit for generating a fused image being according to a second embodiment.

[0037] An example of an optical sighting system 10 is illustrated by Figure 1.

[0038] Such an optical sighting system (or sight) is designed to be mounted or integrated into a firing system. The firing system is designed to fire projectiles, such as bullets. The firing system is, for example, a weapon such as a handgun or a rifle. The firing system has a firing axis, also called the barrel axis.

[0039] The optical sighting system 10 is designed to assist a user of the firing system in aiming. For example, the optical sighting system 10 can display indications of the anticipated point of impact of a projectile fired by the firing system or additional information about the scene observed by the user in direct vision (e.g., displaying thermal images superimposed on the direct view of the scene). The scene is the portion of space within the field of vision of a user of the optical sighting system 10.

[0040] As illustrated by Figure 1, the optical sighting system 10 comprises a separation unit 20, a first optical path 22, a second optical path 24, an image capture and processing unit 26, and a unit 28 for generating a fused image.

[0041] The separation unit 20 is designed to receive an incident optical flux Fl, and to spectrally separate this incident optical flux Fl into a first optical flux F1 and a second optical flux F2. The first optical flux F1 is in a first band of wavelengths. The second optical flux F2 is in a second band of wavelengths.

[0042] Due to spectral separation, the first and second wavelength bands are distinct. However, it is not impossible that the first and second wavelength bands share some wavelengths, or even overlap.

[0043] In one example, the first band of wavelengths is between 380 nanometers and 780 nanometers (visible range), and the second band of wavelengths is between 380 nanometers and 5 millimeters (visible and infrared range).

[0044] Preferably, the second wavelength band is between 780 nm and 5 millimeters (infrared range). Advantageously, the second wavelength band is in the mid-infrared (3 pm to 50 pm) and / or in the far-infrared (50 pm to 5 mm), which allows for the formation of a thermal image of the scene.

[0045] In one example embodiment, the separation unit 20 comprises:

[0046] - a subset of separation 30 of the incident optical flux Fl into the first optical flux F1 and the second optical flux F2, and

[0047] - a reflective subset 32 ​​suitable for reflecting one of the first optical fluxes

[0048] F1 and the second optical flux F2 so that the first optical flux F1 and the second optical flux F2 propagate in substantially parallel directions.

[0049] In a first embodiment, as illustrated in Figure 2, the separation sub-assembly 30 comprises a separating blade 40 (e.g., a glass blade). Alternatively, the separating blade 40 is replaced by a separating cube.

[0050] In this example, the first band of wavelengths is in the visible spectrum, and the second band of wavelengths is in the infrared (preferably mid-infrared and / or far-infrared). The beam splitter 40 is designed to transmit the first optical flux F1 in the visible spectrum and to reflect the second optical flux F2 in the infrared. In this example, the reflective subassembly 32 is optimized for infrared reflection. Alternatively, the beam splitter 40 is designed to reflect the first optical flux F1 in the visible spectrum and to transmit the second optical flux F2 in the infrared. In this case, the reflective subassembly 32 is optimized for visible reflection.

[0051] In a second embodiment, as illustrated by Figure 3, the separation subset 30 comprises a central zone 42 suitable for reflecting an optical flux in one of the first and second wavelength bands and a peripheral zone 44, surrounding the central zone 42, suitable for transmitting an optical flux in the other of the first and second wavelength bands, making it possible to obtain the first optical flux F1 and the second optical flux F2.

[0052] As illustrated in Figure 3, the central zone 42 is, for example, formed by a reflecting mirror 46 in the first or second wavelength band. The peripheral zone 44 is formed by the absence of any component. The reflecting mirror 46 is, for example, held in the central zone 42 of the incident optical flux Fl by a supporting structure 48 so that the central portion of the incident optical flux Fl is reflected by the reflecting mirror 46 and the peripheral portion of the incident optical flux Fl is directly captured by one of the optical paths.

[0053] In this example, the first band of wavelengths is in the visible spectrum, and the second band of wavelengths is in the visible and infrared (preferably mid-infrared and / or far-infrared). The reflecting mirror 46 is designed to reflect the first optical flux F1 in the visible spectrum. The peripheral optical flux in the visible and infrared spectrum is directly captured by the second optical path 24. The first optical flux F1 reflected by the reflecting mirror 46 is then reflected again by the reflecting sub-assembly 32. In this example, the reflecting sub-assembly 32 is optimized for reflection in the visible spectrum (e.g., a mirror with a metallic coating).

[0054] Alternatively, the reflecting mirror 46 is designed to reflect the second optical flux F2 in the infrared. The peripheral optical flux in the visible and infrared ranges is directly captured by the second optical path 24. The second optical flux F2 reflected by the reflecting mirror 46 is then reflected again by the reflecting sub-assembly 32. In this example, the reflecting sub-assembly 32 is optimized for infrared reflection.

[0055] The reflecting sub-assembly 32 is designed to reflect one of the first optical fluxes F1 and the second optical fluxes F2, such that the first optical fluxes F1 and F2 propagate in substantially parallel directions. The reflecting sub-assembly 32 is, for example, formed by a mirror 42 reflecting light in the considered wavelength band (first or second wavelength band).

[0056] Alternatively, the separation unit 20 only performs the separation function, and is for example formed of a separating blade or a separating cube.

[0057] The first optical path 22 is designed to carry the first optical flux F1. When the first optical flux F1 is carried to form an image on a sensor, the carrying process is similar to image capture. When the image is displayed via an eyepiece, the carrying process is similar to image display.

[0058] As can be seen in Figures 4 and 5, the first optical path 22 includes an objective 50 formed from an assembly of one or more optics, such as lenses.

[0059] In one embodiment, as illustrated by figures 4 and 5, the optical axis of the first optical channel 22 forms the aiming axis of the optical aiming system 10. Other configurations are nevertheless possible with a aiming axis different from the optical axis of the first optical channel 22 and the second optical channel 24. In one embodiment, a reticle R (see figure 4) is positioned on the optical path of the first optical channel 22, preferably in a focal plane, making it possible to materialize the aiming axis.

[0060] The second optical path 24 is designed to capture the second optical flux F2. As seen in figures 4 and 5, the second optical path 24 comprises an objective 52 formed from an assembly of one or more optics, such as lenses.

[0061] The image capture and processing unit 26 is designed to generate an image, called the captured image, from the second optical flow F2 captured by the second optical channel 24.

[0062] As illustrated in the examples in Figures 4 and 5, the image capture and processing unit 26 includes an optical assembly 60 for focusing the second beam onto a sensor 62 equipped with processing electronics 64. The optical assembly 60 is formed from an assembly of one or more optics, such as lenses

[0063] The image generation unit 28 is designed to generate an image, known as a fused image. The fused image can be viewed by a user of the optical viewing system 10 and results from the fusion of a reproduction of the captured image and an image from the first optical stream F1 carried by the first optical channel 22.

[0064] In an example implementation, illustrated by Figure 4, the merged image generation unit 28 comprises:

[0065] - a display 70 suitable for displaying the image captured by the second optical channel 24.

[0066] - a combining optic 72 of the optical flux from the captured image displayed on the display 70 with the first optical flux F1 routed (here restored) by the first optical channel 22 to obtain a combined optical flux. The combining optic 72 is, for example, a beam splitter cube (as in Figure 4) or a beam splitter plate.

[0067] - a 74 eyepiece to form the fused image from the combined optical flow.

[0068] In this example, the user observes the restored image of the second optical flow F2 (captured image) superimposed on the direct view of the scene.

[0069] In an example implementation, illustrated in Figure 5, the generation unit 28 comprises:

[0070] - an additional image capture and processing unit 76 capable of generating an image, called an additional image, based on the first optical flux F1 conveyed (here captured) by the first optical channel 22. The additional unit 76 includes, for example, an optical assembly 80 capable of focusing the first optical flux F1 onto a sensor 82 equipped with processing electronics 84. The optical assembly 80 consists of an assembly of one or more optics, such as lenses

[0071] - a display 90 suitable for forming the fused image according to the image captured from the second optical channel 24 and the additional image.

[0072] In this example, the user observes the image displayed by display 90.

[0073] As an optional complement, the additional unit 76 includes an image intensifier tube designed to amplify the first optical flux F1, so that the additional image is an amplified image of the first optical flux F1.

[0074] In one embodiment, the different blocks are modular. For example, the second optical channel 24 and the image capture and processing unit 26 can be detached from the other blocks, allowing the optical aiming system 10 to be used only with a flux in the first wavelength band.

[0075] An example of the operation of the optical sighting system 10 will now be described.

[0076] The optical separation unit 20 receives an incident optical flux Fl which it spectrally separates into a first optical flux F1 and a second optical flux F2.

[0077] The first optical flow F1 is routed (captured or returned) by the first optical channel 22.

[0078] The second optical flux F2 is captured by the second optical channel 24.

[0079] The image capture and processing unit 26 generates an image, called the captured image, from the second optical stream F2 captured by the second optical channel 24.

[0080] The image generation unit 28 generates a fused image viewable by a user of the optical viewing system 10. This image results from the fusion of a rendered image from the second optical channel 24 and an image from the first optical stream F1, which is routed through the first optical channel 22. In a first embodiment illustrated in Figure 4, the fused image results from the superimposition of a rendered image from the second optical channel 24 in the direct view of the scene. In a second embodiment illustrated in Figure 5, the fused image results from the digital superimposition of an image from the first optical channel 22 and an image from the second optical channel 24.

[0081] Thus, the optical viewing system 10 uses a spectral splitter to capture a scene in distinct spectral bands, including infrared and direct visible light, along the same viewing axis. This eliminates the parallax problem.

[0082] Furthermore, optical fusion between the different spectral bands allows for perfect image superposition regardless of the distance at which the target is observed.

[0083] A person skilled in the art will understand that the embodiments and variants previously described can be combined to form new embodiments provided they are technically compatible.

Claims

9 DEMANDS 1. Optical sighting system (10) comprising: - a separation unit (20) suitable for spectrally separating an incident optical flux (Fl) into a first optical flux (F1) and a second optical flux (F2), the first optical flux (F1) being in a first band of wavelengths, the second optical flux (F2) being in a second band of wavelengths, - a first optical path (22) for the routing of the first optical flux (F1), - a second optical channel (24) for capturing the second optical flux (F2), - an image capture and processing unit (26) capable of generating an image, called the captured image, from the second optical stream (F2) captured by the second optical channel (24), and - a unit (28) for generating an image, called a fused image, the fused image being viewable by a user of the optical viewing system (10) and resulting from the fusion of a rendering of the captured image and an image from the first optical flow (F1) routed by the first optical path (22).

2. System according to claim 1, wherein the separation unit (20) comprises: - a subset of separation (30) of the incident optical flux (Fl) into the first optical flux (F1) and the second optical flux (F2), and - a reflective subset (32) suitable for reflecting one of the first optical flux (F1) and the second optical flux (F2) so that the first optical flux (F1) and the second optical flux (F2) propagate in substantially parallel directions.

3. System according to claim 2, wherein the separation subassembly (30) comprises a separating blade (40) or a separating cube.

4. System according to claim 2, wherein the separation sub-assembly (30) comprises a central zone (42) adapted to reflect an optical flux in one of the first and second wavelength bands and a peripheral zone (44) adapted to transmit an optical flux in the other of the first and second wavelength bands, making it possible to obtain the first optical flux (F1) and the second optical flux (F2).

5. System according to claim 4, wherein the central area (42) is formed of a reflective mirror (46) in the first or second band of wavelengths.

6. System according to any one of claims 2 to 5, wherein the reflecting subassembly (32) is formed of a reflecting mirror (42) in the first or second band of wavelengths.

7. System according to any one of claims 1 to 6, wherein the first wavelength band is between 380 nanometers and 780 nanometers, the second wavelength band being between 380 nanometers and 5 millimeters, preferably between 780 nanometers and 5 millimeters, advantageously between 3 micrometers and 5 millimeters.

8. A system according to any one of claims 1 to 7, wherein the generation unit (28) comprises: - a display (70) suitable for displaying the image captured by the second optical channel (24), - a combining optics (72) of the optical flux from the captured image displayed on the display (70) with the first optical flux (F1) routed through the first optical path (22) to obtain a combined optical flux, and - an eyepiece (74) to form the fused image from the combined optical flow.

9. A system according to any one of claims 1 to 8, wherein the generation unit (28) comprises: - an additional image capture and processing unit (76) capable of generating an image, called an additional image, as a function of the first optical flux (F1) conveyed by the first optical path (22), and - a display (90) suitable for forming the fused image according to the captured image from the second optical channel (24) and the additional image.

10. Set comprising: - a firing system, and - an optical sighting system (10) according to any one of claims 1 to 9.

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