Low-light night vision device optical structure with single objective lens

Abstract

The utility model provides a low-light night vision device optical structure with a single objective lens, and the structure comprises an objective lens barrel which is internally provided with a first limiting barrel body, a second limiting barrel body, a third limiting barrel body, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens in sequence from the object side to the image side in the optical axis direction. The fifth lens is attached to the sixth lens; and the first mounting groove, the second mounting groove, the third mounting groove, the fourth mounting groove and the fifth mounting groove share the same central axis. The optical path difference of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens is reduced, so that when light enters the lenses at the same incident angle, the light passes through the lenses along similar paths, the phase difference is reduced, and the imaging quality is improved; and meanwhile, light rays can be ensured to irradiate on the lens in a coaxial manner, so that the illumination of the surface of the lens is more uniform, and the imaging quality is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of low-light night vision, and particularly relates to a low-light night vision optical structure with a single objective lens. BACKGROUND

[0002] Low-light night vision refers to an instrument for observing at night by using natural night light such as moonlight, starlight, atmospheric glow and galaxy light as illumination, amplifying and converting weak photons reflected by a target into visible images by means of an image intensifier, so as to realize night observation. Low-light night vision is not easy to expose itself because it does not use infrared searchlights and other active illumination targets during work, and has lower power consumption than low-illumination CMOS devices, so it is more suitable for field reconnaissance observation and is mainly applied to military operations, special police operations and customs anti-smuggling.

[0003] At present, low-light night vision can be divided into single-tube monocular, single-tube binocular and double-tube binocular night vision according to structure, and generally includes an objective lens, an image intensifier system, an eyepiece and a collimating system arranged between the image intensifier system and the eyepiece. The coaxial alignment of lenses is crucial in the installation of low-light night vision because it is directly related to the imaging quality and stability of the system. If the lenses are not accurately aligned on the same optical axis, the light will be offset when passing through, thereby affecting the clarity and accuracy of the image. Therefore, an optical structure for coaxial alignment of a low-light night vision instrument with a single objective lens is proposed to improve the imaging effect. CONTENT OF THE INVENTION

[0004] Therefore, the main purpose of the application is to provide a low-light night vision optical structure with a single objective lens.

[0005] The technical solution adopted by the application is as follows: a low-light night vision optical structure with a single objective lens, comprising an objective lens barrel, wherein a first limiting barrel, a second limiting barrel and a third limiting barrel are sequentially arranged along the optical axis direction from the object side to the image side in the objective lens barrel;

[0006] A first installation groove is formed in the inner circumferential surface of the first limiting barrel, and a first lens is installed in the first installation groove;

[0007] A second installation groove is formed in the inner circumferential surface of the second limiting barrel, and a second lens is installed in the second installation groove;

[0008] The third limiting barrel is arranged in a spaced manner with the second limiting barrel and forms a third installation groove with the inner end surface of the objective lens barrel, and a third lens is installed in the third installation groove;

[0009] A fourth installation groove is formed in the tail end inner wall of the objective lens barrel, and a fourth lens is installed in the fourth installation groove;

[0010] The fourth installation slot forms a fifth installation slot with the third limiting cylinder and the inner wall of the objective lens cylinder, and the fifth lens and the sixth lens are installed in the fifth installation slot.

[0011] The first installation slot, the second installation slot, the third installation slot, the fourth installation slot, and the fifth installation slot share the same central axis.

[0012] Further, the first lens is convex near the optical axis on the object side and concave near the optical axis on the image side.

[0013] The second lens is concave near the optical axis on the object side and convex near the optical axis on the image side.

[0014] The third lens is convex near the optical axis on the object side and planar near the optical axis on the image side.

[0015] The fourth lens is convex near the optical axis on the object side and convex near the optical axis on the image side.

[0016] The fifth lens is convex near the optical axis on the object side and planar near the optical axis on the image side.

[0017] The sixth lens is planar near the optical axis on the object side and concave near the optical axis on the image side.

[0018] Further, the fifth lens and the sixth lens are of the same height.

[0019] Further, the inner wall of the second limiting cylinder forms a slope away from the second installation slot and towards the third limiting cylinder, and the height of the slope gradually decreases as it approaches the third limiting cylinder.

[0020] Further, the inner diameter of the third cylinder gradually decreases from the third lens to the fifth lens.

[0021] Further, a reflecting mirror is provided behind the fourth lens in the objective lens cylinder in the direction of incoming light, and an enhancement element is connected behind the reflecting mirror.

[0022] Further, the first limiting cylinder, the second limiting cylinder, and the third limiting cylinder are respectively detachably connected with the objective lens cylinder.

[0023] Compared with the prior art, the application has the beneficial effects that: by sharing the same central axis by the first mounting groove, the second mounting groove, the third mounting groove, the fourth mounting groove and the fifth mounting groove, the optical path difference of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens is reduced, so that when the light rays enter the lens at the same incidence angle, they will pass through the lens along similar paths, thereby reducing the phase difference and improving the imaging quality; meanwhile, the light rays can be ensured to irradiate the lens in a coaxial manner, so that the illumination of the lens surface is more uniform, thereby improving the imaging quality. BRIEF DESCRIPTION OF DRAWINGS

[0024] The following drawings only schematically illustrate and explain the application and do not serve to limit the scope of the application, in which:

[0025] Figure 1 It is a schematic diagram of the cross-sectional structure of the application.

[0026] The reference signs are as follows: 10. objective lens barrel; 11. first limiting barrel; 12. second limiting barrel; 12a. slope surface; 13. third limiting barrel; 14. first mounting groove; 15. first lens; 16. second mounting groove; 17. second lens; 18. third mounting groove; 19. third lens; 20. fourth mounting groove; 21. fourth lens; 22. fifth mounting groove; 23. fifth lens; 24. sixth lens. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme, design method and advantages of the application more clear and understandable, the application is further described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the application and do not serve to limit the application.

[0028] Reference Figure 1 The application provides a kind of low-light night vision optical structure with single objective, including objective lens barrel 10, the first limiting barrel 11, second limiting barrel 12 and third limiting barrel 13 are sequentially installed in the objective lens barrel 10 along the optical axis direction from object side to image side;

[0029] In the above, the first limiting barrel 11 inner wall surface is provided with first mounting groove 14, and the first mounting groove 14 is provided with first lens 15; the first lens 15 is convex on the object side near the optical axis, and is concave on the image side near the optical axis;

[0030] In the above, the second limiting barrel 12 inner wall surface is provided with second mounting groove 16, and the second mounting groove 16 is provided with second lens 17; the second lens 17 is concave on the object side near the optical axis, and is convex on the image side near the optical axis;

[0031] In the above, the third limiting cylinder 13 is arranged apart from the second limiting cylinder 12 and forms a third mounting groove 18 with the inner end face of the objective lens barrel 10, and the third lens 19 is mounted in the third mounting groove 18; the third lens 19 is convex on the object side near the optical axis and is flat on the image side near the optical axis;

[0032] In the above, the tail end inner wall of the objective lens barrel 10 is provided with a fourth mounting groove 20, and the fourth lens 21 is mounted in the fourth mounting groove 20; the fourth lens 21 is convex on the object side near the optical axis and is convex on the image side near the optical axis, and a reflecting mirror 30 is arranged behind the fourth lens 21 in the objective lens barrel 10 along the direction of light entering, and an enhancer is connected behind the reflecting mirror 30, which is an image enhancer and is a product in the prior art; the reflecting mirror 30 is a right-angle prism, which can make the light path from the object side to the image side turn and achieve the purpose of reducing the size of the night vision device;

[0033] In the above, the outer wall of the fourth mounting groove 20 towards the third limiting cylinder 13 forms a fifth mounting groove 22 with the third limiting cylinder 13 and the inner wall of the objective lens barrel 10, and the fifth lens 23 and the sixth lens 24 are mounted in the fifth mounting groove 22, and the fifth lens 23 is in contact with the sixth lens 24; the fifth lens 23 is convex on the object side near the optical axis and is flat on the image side near the optical axis; the sixth lens 24 is flat on the object side near the optical axis and is concave on the image side near the optical axis, and the fifth lens 23 and the sixth lens 24 are of the same height.

[0034] In the above, as shown in Figure 1 , the first limiting cylinder 11, the second limiting cylinder 12 and the third limiting cylinder 13 are respectively detachably connected with the objective lens barrel 10, and the first mounting groove 14, the second mounting groove 16, the third mounting groove 18, the fourth mounting groove 20 and the fifth mounting groove 22 share the same central axis, which reduces the light path difference of the first lens 15, the second lens 17, the third lens 19, the fourth lens 21, the fifth lens 23 and the sixth lens 24, so that when the light enters the lenses at the same incidence angle, they will pass through the lenses along similar paths, thereby reducing the phase difference and improving the imaging quality; at the same time, it can ensure that the light irradiates the lenses in a coaxial manner, so that the illumination of the lens surface is more uniform, thereby improving the imaging quality.

[0035] As an embodiment of the present application, as shown in Figure 1 , in the optical structure of the low-light-level night vision device with a single objective lens, the inner wall surface of the second limiting cylinder 12 gradually decreases in height as it moves away from the second mounting groove 16 and approaches the third limiting cylinder to form a slope surface 12a.

[0036] As an embodiment of the present application, referring to Figure 1 As shown in the optical structure of the low-light-level night vision device with a single objective, the inner diameter of the third barrel 13 gradually decreases from the third lens 19 to the fifth lens 23.

[0037] The above has described various embodiments of the present application, the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles, practical applications, or technical improvements in the market of the embodiments, or to enable other ordinary skilled in the art to understand the embodiments disclosed herein.

Claims

1. An optical structure for a low-light night vision device with a single objective lens, characterized in that, Includes an objective lens tube (10), in which a first limiting tube (11), a second limiting tube (12) and a third limiting tube (13) are installed sequentially from the object side to the image side along the optical axis; The first limiting cylinder (11) has a first mounting groove (14) on its inner circumferential surface, and a first lens (15) is installed in the first mounting groove (14). The second limiting cylinder (12) has a second mounting groove (16) on its inner circumferential surface, and a second lens (17) is installed in the second mounting groove (16); The third limiting cylinder (13) is spaced apart from the second limiting cylinder (12) and forms a third mounting groove (18) with the inner end face of the objective lens cylinder (10). A third lens (19) is installed in the third mounting groove (18). The inner wall of the tail end of the objective lens tube (10) is provided with a fourth mounting groove (20), and a fourth lens (21) is installed in the fourth mounting groove (20). The fourth mounting groove (20) forms a fifth mounting groove (22) with the outer wall of the third limiting cylinder (13) and the inner wall of the objective lens tube (10). A fifth lens (23) and a sixth lens (24) are installed in the fifth mounting groove (22). The fifth lens (23) and the sixth lens (24) are in contact with each other. The first mounting slot (14), the second mounting slot (16), the third mounting slot (18), the fourth mounting slot (20), and the fifth mounting slot (22) share the same central axis.

2. The optical structure of a low-light night vision device with a single objective lens according to claim 1, characterized in that, The first lens (15) has a convex surface on the object side near the optical axis and a concave surface on the image side near the optical axis; The second lens (17) has a concave surface on the object side near the optical axis and a convex surface on the image side near the optical axis; The third lens (19) is convex on the object side near the optical axis and flat on the image side near the optical axis; The fourth lens (21) is convex on the object side near the optical axis and on the image side near the optical axis; The fifth lens (23) is convex on the object side near the optical axis and flat on the image side near the optical axis; The sixth lens (24) is a plane on the object side near the optical axis and a concave surface on the image side near the optical axis.

3. The optical structure of a low-light night vision device with a single objective lens according to claim 1 or 2, characterized in that, The fifth lens (23) is at the same height as the sixth lens (24).

4. The optical structure of a low-light night vision device with a single objective lens according to claim 1, characterized in that, The inner wall surface of the second limiting cylinder (12) forms a slope (12a) as it moves away from the second mounting groove (16) and closer to the third limiting cylinder (13), and the height of the slope (12a) gradually decreases as it moves closer to the third limiting cylinder (13).

5. The optical structure of a low-light night vision device with a single objective lens according to claim 1, characterized in that, The inner diameter of the third limiting cylinder (13) gradually decreases from the third lens (19) toward the fifth lens (23).

6. The optical structure of a low-light night vision device with a single objective lens according to claim 1, characterized in that, Along the direction of light entry, a reflector (30) is provided behind the fourth lens (21) in the objective lens tube (10), and an enhancement member is connected behind the reflector (30).

7. The optical structure of a low-light night vision device with a single objective lens according to claim 1, characterized in that, The first limiting cylinder (11), the second limiting cylinder (12) and the third limiting cylinder (13) are detachably connected to the objective lens tube (10).

Images