A low-light-level optical system

Abstract

The present application relates to a low-light-level night vision optical system, comprising a right visual system and a left visual system; the right visual system comprises a low-light-level system, a first lens, a double-wedge mirror group, a first turning lens group, a catadioptric lens group and a right eyepiece group arranged in sequence along the same optical axis direction; the double-wedge mirror group receives incident light of the first lens and divides the incident light into right visual light and left visual light, and the right visual light enters the first turning lens group along the optical axis direction; the left visual system comprises the low-light-level system, the first lens, the double-wedge mirror group, a second turning lens group, a first mirror and a left eyepiece group arranged in sequence along the same optical axis direction; the second turning lens group is used for receiving the left visual light. The low-light-level night vision optical system provided by the present application has simple structure, fewer lenses, smaller volume and weight, and compact form; and the double-image problem is solved through a specific wedge angle.

Description

Technical Field

[0001] This invention relates to the field of low-light night vision technology, and more particularly to a low-light night vision optical system. Background Technology

[0002] Helmet-mounted low-light night vision devices are head-mounted devices that improve visibility at night or in low-light conditions through light enhancement technology. However, these devices are complex and heavy. If mounted on a helmet frame in front of the wearer's eyes, it shifts the helmet's center of gravity forward, increasing the load on the neck and subjecting it to a forward tilting torque, leading to fatigue and neck injury. Therefore, developing a lightweight helmet-mounted low-light night vision optical system is crucial to reducing user burden. Summary of the Invention

[0003] In view of this, it is necessary to provide a low-light night vision optical system to solve the problems of complex structure and large weight of existing low-light night vision devices.

[0004] This invention provides a low-light night vision optical system, comprising: a right visual system and a left visual system;

[0005] The right visual system includes a low-light system, a first lens, a double wedge lens group, a first steering lens group, a catadioptric lens group, and a right eyepiece group arranged sequentially along the same optical axis.

[0006] The double wedge lens group receives the incident light from the first lens and divides the incident light into right eye-viewing light and left eye-viewing light. The right eye-viewing light enters the first steering lens group along the optical axis.

[0007] The left visual system includes the low-light system, the first lens, the double wedge lens group, the second steering lens group, the first reflecting mirror, and the left eyepiece group arranged sequentially along the same optical axis.

[0008] The second steering lens group is used to receive the left eye's visual light.

[0009] Furthermore, the low-light system includes a low-light objective lens group and an image intensifier. The low-light objective lens group is used to capture scene images, and the image intensifier is used to enhance and magnify the scene images and perform imaging.

[0010] Furthermore, the low-light objective lens group includes a first low-light lens, a second low-light lens, a first cemented low-light lens, and a third low-light lens. The first low-light lens and the second low-light lens are respectively arranged along the optical axis. The first low-light lens is made of ACRYLIC material, and the convex surface of the second low-light lens near the first low-light lens is an even-order aspherical surface.

[0011] Furthermore, the low-light system also includes a second mirror, which is disposed between the low-light objective lens group and the image intensifier along the optical axis.

[0012] Furthermore, the double wedge lens assembly includes a first wedge lens and a second wedge lens arranged sequentially along the optical axis, with the wedge surfaces of the first wedge lens and the second wedge lens arranged in opposite directions, and the wedge surface of the first wedge lens being close to the first turning lens.

[0013] Furthermore, both the first wedge mirror and the second wedge mirror have a semi-transparent, semi-reflective coating.

[0014] Furthermore, the first steering lens group includes a second lens and a first translucent lens arranged sequentially along the optical axis, with the convex surface of the second lens close to the first translucent lens and the concave surface of the first translucent lens close to the catadioptric lens group.

[0015] Furthermore, the catadioptric lens group includes a third reflecting mirror, a third lens, and a fourth reflecting mirror arranged sequentially along the optical axis. The third reflecting mirror and the fourth reflecting mirror are distributed in parallel. The convex surface of the third lens faces the third reflecting mirror, and the concave surface of the third lens faces the fourth reflecting mirror.

[0016] Furthermore, the second steering lens group includes a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis. The convex surface of the fourth lens is distributed toward the direction of the fifth lens, the concave surface of the fifth lens is distributed toward the direction of the sixth lens, and the convex surface of the sixth lens is distributed toward the first reflecting mirror.

[0017] Furthermore, the projection system includes a projection assembly, the double wedge lens group, the first steering lens group, the catadioptric lens group, and the right eyepiece group arranged sequentially along the optical axis.

[0018] Compared with existing technologies, the low-light night vision optical system adopted in this invention splits the scene image transmitted from the low-light system and the first lens into right and left visual light by setting up a double wedge lens group. This allows the right visual light to enter the right eye for observation through the first steering lens group, the catadioptric mirror group, and the right eyepiece group, while the left visual light enters the left eye for observation through the second steering lens group, the first reflector, and the left eyepiece group, thus achieving binocular vision. At the same time, the catadioptric mirror group changes the right visual light path, making the low-light night vision optical system device simple and compact in structure, reducing the device size, and making it more convenient to wear.

[0019] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of an embodiment of the low-light night vision optical system provided by the present invention. Detailed Implementation

[0021] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0022] This invention provides a low-light night vision optical system; please refer to [link / reference]. Figure 1 This includes: the right visual system and the left visual system;

[0023] The right visual system includes a low-light system 1, a first lens 2, a double wedge lens group 3, a first steering lens group 4, a catadioptric lens group 5, and a right eyepiece group 6 arranged sequentially along the same optical axis.

[0024] The double wedge lens group 3 receives the incident light from the first lens 2 and divides the incident light into right eye-viewing light and left eye-viewing light. The right eye-viewing light enters the first steering lens group 4 along the optical axis.

[0025] The left visual system includes the low-light system 1, the first lens 2, the double wedge lens group 3, the second steering lens group 7, the first reflecting mirror 8 and the left eyepiece group 9 arranged sequentially along the same optical axis.

[0026] The second steering lens group 7 is used to receive the left eye's vision light.

[0027] In this embodiment, by setting up a double wedge lens group 3, the scene image transmitted from the low-light system 1 and the first lens 2 is divided into right eye vision light and left eye vision light. This allows the right eye vision light to enter the right eye for observation through the first steering lens group 4, the catadioptric mirror group and the right eyepiece group 6, and also allows the left eye vision light to enter the left eye for observation through the second steering lens group 7, the first reflector 8 and the left eyepiece group 9, thus realizing binocular vision. At the same time, the catadioptric mirror group changes the right eye vision light path, making the low-light night vision optical system device simple and compact in structure, reducing the size of the device, and making it easier to wear.

[0028] It should be noted that when traditional designs need to meet the requirements of a 60-degree field of view, 65mm interpupillary distance, 10mm exit pupil diameter, and 20mm exit pupil distance, they generally use five to six lenses or only aspherical lenses, resulting in a complex structure and a large size and weight. In this embodiment, the right eyepiece group 6 is sequentially provided with an eyepiece first lens, an eyepiece second lens, and an eyepiece third lens along the optical axis. The structure of the right eyepiece group 6 and the left eyepiece group 9 is the same, the difference being the coating requirements. The right eyepiece group 6 is coated with an anti-reflection coating of 500nm-650nm, while the left eyepiece group 9 is coated with an anti-reflection coating of 500nm-600nm and a cutoff coating of 610nm-650nm to prevent the left eyepiece group 9 from seeing the projected image and producing double images or ghosting. The second eyepiece lens is made of ACRYLIC material, and the convex surface facing the eye is designed with an even-order aspherical surface. While meeting the requirements of a system field of view of 60 degrees, interpupillary distance of 65mm, exit pupil diameter of 10mm, and exit pupil distance of 20mm, the number of lenses is reduced, the structure is simplified, and the size and weight of the eyepiece system are reduced.

[0029] In some embodiments, the low-light system 1 includes a low-light objective lens group 11 and an image intensifier 12. The low-light objective lens group is used to capture scene images, and the image intensifier is used to enhance and magnify the scene images and perform imaging.

[0030] In this embodiment, the function of the low-light system 1 is to bring the natural light from the external scene into the low-light objective lens group and onto the image intensifier. The image intensifier outputs the image through 1x photoelectric conversion, so that the observer can observe a clearer image through the left eyepiece group 9 and the right eyepiece.

[0031] In one specific embodiment, the field of view of the low-light objective lens group is 60 degrees and the relative aperture is 1. It is understood that in other embodiments, the field of view and the relative aperture may be other values.

[0032] In some embodiments, the low-light objective lens group 11 includes a first low-light lens 111, a second low-light lens 112, a first cemented low-light lens 113, and a third low-light lens 114. The first low-light lens 111 and the second low-light lens 112 are respectively arranged along the optical axis. The first low-light lens 111 is made of ACRYLIC material, and the convex surface of the second low-light lens 112 near the first low-light lens 111 is an even-order aspherical surface.

[0033] It should be noted that when traditional low-light objective lens groups need to meet the requirements of a large field of view and a large relative aperture, they generally use eight to ten lenses or only aspherical lenses, resulting in a complex structure and a large size and weight.

[0034] Furthermore, in this embodiment, the first bonded micro-light lens is formed by bonding two micro-light lenses together. It is understood that in other embodiments, the first bonded micro-light lens may also be formed by bonding other numbers of micro-light lenses together, and the specific configuration can be set according to actual needs.

[0035] In this embodiment, the first low-light lens 111 is made of ACRYLIC material, and the convex surface facing the object in the second low-light lens 112 is designed as an even-order aspherical surface. While satisfying the system field of view of 60 degrees and the relative aperture of 1, the number of lenses is reduced, the structure is simple, and the volume and weight of the low-light system 1 are small.

[0036] It should be noted that ACRYLIC material is a polymer material, commonly known as acrylic, plexiglass, or PMMA (polymethyl methacrylate). ACRYLIC is a colorless, transparent, high-hardness, heat-resistant, UV-resistant, and chemically resistant polymer. It possesses excellent mechanical and processing properties, is easy to cut, drill, and bend, and can be manufactured into components and products of various shapes and sizes. ACRYLIC has excellent light transmittance; compared to glass, it is lighter, more impact-resistant, and less prone to breakage, thus it is widely used in high-end merchandise displays and advertising. In this embodiment, the first micro-light lens uses ACRYLIC material, which possesses the characteristics of good light transmittance, light weight, durability, and ease of processing.

[0037] In some embodiments, the low-light system 1 further includes a second mirror 13, which is disposed between the low-light objective lens group and the image intensifier along the optical axis.

[0038] It should be noted that by designing the second reflector 13 to increase the number of reflectors in the low-light night vision optical system, multiple reflections can be made in the light path, resulting in a smaller interpupillary distance between the left and right eyepiece groups and a more compact system configuration.

[0039] In some embodiments, the double wedge lens group 3 includes a first wedge lens 31 and a second wedge lens 32 arranged sequentially along the optical axis. The wedge surfaces of the first wedge lens 31 and the second wedge lens 32 are arranged in opposite directions, and the wedge surface of the first wedge lens 31 is close to the first turning lens.

[0040] It should be noted that traditional beam splitting methods generally use right-angle prisms or beam splitters. Right-angle prisms are relatively heavy and bulky, while beam splitters can easily cause double images to appear in the left visual system.

[0041] In this embodiment, the dual wedge mirror group 3 consists of a first wedge mirror 31 and a second wedge mirror 32 arranged sequentially along the optical axis. The first wedge mirror 31 reflects the incident light at a 90-degree angle, with the wedge angle of the first wedge mirror 31 pointing upwards and the wedge angle of the second wedge mirror 32 pointing downwards, with a wedge angle of 3.25 degrees. The coating of the first wedge mirror 31 and the second wedge mirror 32 is 500nm-650nm semi-transparent and semi-reflective. 50% of the green light is reflected by the first wedge mirror 31 to the right visual system, 50% of the green light is transmitted through the first wedge mirror 31 and the second wedge mirror 32 to the left visual system, and 50% of the red light is transmitted through the first wedge mirror 31 and the second wedge mirror 32 to the right projection system. By using dual wedge mirrors for beam splitting, not only is the size and weight reduced, but the problem of double projection is also solved by the specific wedge angle.

[0042] In some embodiments, the first steering lens group 4 includes a second lens 41 and a first translucent lens 42 arranged sequentially along the optical axis, wherein the convex surface of the second lens 41 is close to the first translucent lens 42, and the concave surface of the first translucent lens 42 is close to the catadioptric lens group 5.

[0043] In this embodiment, by setting the second lens 41 and the first translucent lens 42 to form the first steering lens group 4, aberration compensation can be performed on the light of the double wedge lens group 3.

[0044] In some embodiments, the catadioptric lens group 5 includes a third reflecting mirror 51, a third lens 52, and a fourth reflecting mirror 53 arranged sequentially along the optical axis. The third reflecting mirror 51 and the fourth reflecting mirror 53 are distributed in parallel. The convex surface of the third lens 52 faces the third reflecting mirror 51, and the concave surface of the third lens 52 faces the fourth reflecting mirror 53.

[0045] In this embodiment, the function of the catadioptric lens group 5 is to refract the incident light rays, shorten the eyepiece interpupillary distance, and make the system structure compact;

[0046] It should be noted that traditional methods for shortening interpupillary distance generally use prisms to refract light rays, and prisms are relatively heavy and bulky.

[0047] In some embodiments, the second steering lens group 7 includes a fourth lens 71, a fifth lens 72, and a sixth lens 73 arranged sequentially along the optical axis. The convex surface of the fourth lens 71 is distributed toward the direction of the fifth lens, the concave surface of the fifth lens is distributed toward the direction of the sixth lens, and the convex surface of the sixth lens is distributed toward the first reflecting mirror 8.

[0048] In this embodiment, the function of the second steering lens group 7 is to compensate for aberrations in the light entering the left eye; the fourth lens 71 and the sixth lens 73 are made of ACRYLIC material, which reduces the number of lenses and simplifies the structure, making the second steering lens group 7 smaller in size and weight, and further reducing the weight of the optical system.

[0049] In some embodiments, a projection system is also included, which includes a projection assembly 10, the double wedge lens group 3, the first steering lens group 4, the catadioptric lens group 5, and the right eyepiece group 6 arranged sequentially along the optical axis.

[0050] In this embodiment, the projection system provides the image on the projection component to the right eye for observation. The projection component includes an OLED screen and a first projection lens arranged sequentially along the optical axis, with the concave surface of the first projection lens facing the OLED screen. The projection component enables the right eye to observe the image on the OLED screen. The first projection lens is made of ACRYLIC material, and its concave surface facing the double wedge lens group 3 adopts an even-order aspherical design, reducing the number of lenses in the projection component and simplifying the structure.

[0051] Furthermore, given the limited size, the system design incorporates projection capabilities, thereby increasing the high functional density of the optical system.

[0052] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A low-light night vision optical system, characterized in that, include: Right visual system and left visual system; The right visual system includes a low-light system, a first lens, a double wedge lens group, a first steering lens group, a catadioptric lens group, and a right eyepiece group arranged sequentially along the same optical axis. The double wedge lens group includes a first wedge lens and a second wedge lens arranged sequentially along the optical axis. The wedge surfaces of the first wedge lens and the second wedge lens are arranged in opposite directions, and the wedge surface of the first wedge lens is close to the first steering lens group. Both the first wedge lens and the second wedge lens have a semi-transparent and semi-reflective coating. The wedge angle of the first wedge lens faces upward, and the wedge angle of the second wedge lens faces downward, with a wedge angle of 3.25 degrees. The double wedge lens group receives the incident light from the first lens and divides the incident light into right eye-viewing light and left eye-viewing light. The right eye-viewing light enters the first steering lens group along the optical axis. The left visual system includes the low-light system, the first lens, the double wedge lens group, the second steering lens group, the first reflecting mirror, and the left eyepiece group arranged sequentially along the same optical axis. The second steering lens group is used to receive the left eye's visual light.

2. The low-light night vision optical system according to claim 1, characterized in that, The low-light system includes a low-light objective lens group and an image intensifier. The low-light objective lens group is used to capture scene images, and the image intensifier is used to enhance and magnify the scene images and perform imaging.

3. The low-light night vision optical system according to claim 2, characterized in that, The low-light objective lens group includes a first low-light lens, a second low-light lens, a first cemented low-light lens, and a third low-light lens. The first low-light lens and the second low-light lens are respectively arranged along the optical axis. The first low-light lens is made of ACRYLIC material, and the convex surface of the second low-light lens near the first low-light lens is an even-order aspherical surface.

4. The low-light night vision optical system according to claim 2, characterized in that, The low-light system also includes a second mirror, which is disposed between the low-light objective lens group and the image intensifier along the optical axis.

5. The low-light night vision optical system according to claim 1, characterized in that, The first steering lens group includes a second lens and a first cemented lens arranged sequentially along the optical axis. The convex surface of the second lens is close to the first cemented lens, and the concave surface of the first cemented lens is close to the catadioptric lens group.

6. The low-light night vision optical system according to claim 1, characterized in that, The catadioptric lens group includes a third reflecting mirror, a third lens, and a fourth reflecting mirror arranged sequentially along the optical axis. The third reflecting mirror and the fourth reflecting mirror are distributed in parallel. The convex surface of the third lens faces the third reflecting mirror, and the concave surface of the third lens faces the fourth reflecting mirror.

7. The low-light night vision optical system according to claim 1, characterized in that, The second steering lens group includes a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis. The convex surface of the fourth lens is distributed toward the direction of the fifth lens, the concave surface of the fifth lens is distributed toward the direction of the sixth lens, and the convex surface of the sixth lens is distributed toward the first reflecting mirror.

8. The low-light night vision optical system according to claim 1, characterized in that, It also includes a projection system, which comprises a projection assembly, the double wedge lens group, the first steering lens group, the catadioptric lens group, and the right eyepiece group arranged sequentially along the optical axis.

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