Wide field of view low light level scope optical system

Abstract

The application discloses a wide-visual-range low-illumination sighting telescope optical system, which comprises an objective optical system and an ocular optical system; wherein the objective optical system comprises, in sequence from the light incidence direction to the light emission direction, an objective first lens, an objective first cemented lens, an objective fourth lens, an objective fifth lens and an objective second cemented lens; and the ocular optical system comprises, in sequence from the light incidence direction to the light emission direction, an ocular first cemented lens, an ocular third lens, an ocular fourth lens and an ocular fifth lens.

Description

Technical Field

[0001] This invention relates to the field of optical system design, and more specifically to a wide-range, low-illuminance aiming scope optical system. Background Technology

[0002] Low-light digital rifle sights enable clear target observation in daylight, nighttime, and low-light environments. Suitable for individual combat firearms, they are applied in various specialized industries such as the military, drug enforcement, night surveillance, security, and hunting. Equipped with a low-light, high dynamic range CMOS sensor, the target image is projected onto the CMOS sensor via an optical system. After processing by the control circuit, the image is input into memory. The image is then read from memory to form a video signal, displayed on a screen, and finally magnified by the eyepiece for reception by the human eye.

[0003] Existing low-light digital rifle sights typically employ Pittsval objectives, using a negative lens group as the focusing assembly. This negative lens group allows for focusing on objects at varying distances, ensuring the image remains in a fixed position. However, this focusing system is limited by factors such as a wide operating wavelength, wide viewing distance, high image quality requirements during focusing, and weight constraints, making it difficult to achieve high-quality, clear images within a viewing distance range of 7m to 50m. Traditional Pittsval objectives use a front positive lens group with a low air gap combination of a positive lens and a cemented doublet. This means the front lens group has a large glass diameter, making it difficult to limit the weight of the objective group. Furthermore, the heavy weight of the front positive lens group shifts the center of gravity of the objective optical system forward, complicating weight distribution and hindering product lightweighting.

[0004] Prior art 1 relates to a low-light objective lens optical system with an 85mm focal length, but the total length of the optical system reaches 143mm. Prior art 2 relates to a digital glow-in-the-dark night vision sight objective lens, which uses not only ED glass but also aspherical glass, and has a large number of large-diameter glass elements in the front group, making weight reduction impossible. Prior art 3 relates to an optical system for a low-light digital rifle sight, but does not disclose the focusing range or focusing image quality. Prior art 4 uses glass or plastic aspherical lenses, leading to increased costs and higher requirements for product assembly precision. Summary of the Invention

[0005] The purpose of this invention is to provide a wide-range, low-light aiming scope optical system to simplify the structure of the aiming scope optical system and enable the objective lens to have a wide range of vision.

[0006] To solve the above-mentioned technical problems, the present invention provides a technical solution: a wide-range, low-illuminance aiming scope optical system, the optical system comprising an objective lens optical system and an eyepiece optical system; wherein the objective lens optical system comprises an objective first lens, an objective first cemented lens, an objective fourth lens, an objective fifth lens, and an objective second cemented lens arranged sequentially from the light incident direction to the light exit direction; the eyepiece optical system comprises an eyepiece first cemented lens, an eyepiece third lens, an eyepiece fourth lens, and an eyepiece fifth lens arranged sequentially from the light incident direction to the light exit direction.

[0007] According to the above scheme, in the objective lens optical system, the first objective lens is a plano-convex lens, the first cemented objective lens is formed by cementing the second objective lens and the third objective lens together, the second objective lens is a biconvex lens, the third objective lens is a biconcave lens, the fourth objective lens is a meniscus lens, the fifth objective lens is a biconvex lens, and the second cemented objective lens is formed by cementing the sixth objective lens and the seventh objective lens together, the sixth objective lens is a meniscus lens, and the seventh objective lens is a biconcave lens.

[0008] According to the above scheme, in the eyepiece optical system, the first cemented eyepiece is formed by cementing the first eyepiece lens and the second eyepiece lens together. The first eyepiece lens is a meniscus lens, the second eyepiece lens is a biconcave lens, the third eyepiece lens is a meniscus lens, the fourth eyepiece lens is a biconvex lens, and the fifth eyepiece lens is a plano-convex lens.

[0009] According to the above scheme, the material of the first objective lens is heavy phosphorus crown glass, the material of the second objective lens is fluorine crown glass, the material of the third objective lens is heavy lanthanum flint glass, the material of the fourth objective lens is heavy flint glass, the material of the fifth objective lens is heavy flint glass, the material of the sixth objective lens is heavy flint glass, and the material of the seventh objective lens is heavy lanthanum flint glass.

[0010] According to the above scheme, the material of the first eyepiece lens is heavy lanthanum flint glass, the material of the second eyepiece lens is heavy flint glass, the material of the third eyepiece lens is lanthanum flint glass, the material of the fourth eyepiece lens is lanthanum flint glass, and the material of the fifth eyepiece lens is heavy lanthanum flint glass.

[0011] According to the above scheme, the side radius of curvature of the first objective lens away from the second objective lens is [70mm, 80mm], and the side radius of curvature of the first objective lens close to the second objective lens is infinite.

[0012] The side radius of curvature of the second objective lens away from the third objective lens is [35mm, 45mm], and the side radius of curvature of the second objective lens near the third objective lens is [-110mm, -100mm].

[0013] The radius of curvature of the side of the third objective lens furthest from the second objective lens is [170mm, -180mm].

[0014] The radius of curvature of the side of the fourth objective lens furthest from the fifth objective lens is [145mm, -155mm], and the radius of curvature of the side of the fourth objective lens closest to the fifth objective lens is [40mm, 50mm].

[0015] The radius of curvature of the side of the fifth objective lens furthest from the sixth objective lens is [60mm, 70mm], and the radius of curvature of the side of the fifth objective lens closest to the sixth objective lens is [-70mm, -60mm].

[0016] The side radius of curvature of the sixth objective lens away from the seventh objective lens is [-40mm, -30mm], and the side radius of curvature of the sixth objective lens close to the seventh objective lens is [10mm, 20mm].

[0017] The radius of curvature of the side of the seventh objective lens away from the sixth objective lens is [180mm, 190mm].

[0018] According to the above scheme, the side radius of curvature of the first eyepiece lens away from the second eyepiece lens is [-400mm, -380mm], and the side radius of curvature of the first eyepiece lens near the second eyepiece lens is [-40mm, -20mm].

[0019] The radius of curvature of the side of the second eyepiece lens closest to the third eyepiece lens is infinite.

[0020] The radius of curvature of the side of the third eyepiece lens furthest from the fourth eyepiece lens is [-170mm, -160mm], and the radius of curvature of the side of the third eyepiece lens closest to the fourth eyepiece lens is [30mm, 40mm].

[0021] The radius of curvature of the side of the fourth eyepiece lens furthest from the fifth eyepiece lens is infinite, and the radius of curvature of the side of the fourth eyepiece lens closest to the fifth eyepiece lens is [-60mm, -50mm].

[0022] The radius of curvature of the side of the fifth eyepiece closest to the fourth eyepiece is [50mm, 60mm], and the radius of curvature of the side of the fifth eyepiece furthest from the fourth eyepiece is infinite.

[0023] According to the above scheme, the center thickness of the first objective lens ranges from [7mm to 10mm], the air gap between the first and second objective lenses ranges from [25mm to 35mm], the center thickness of the second objective lens ranges from [10mm to 15mm], the center thickness of the third objective lens ranges from [5mm to 10mm], the air gap between the third and fourth objective lenses ranges from [5mm to 15mm], and the center thickness of the fourth objective lens ranges from [0mm to 5mm]. The air gap between the fourth lens and the fifth objective lens ranges from [20mm to 25mm], the center thickness of the fifth objective lens ranges from [0mm to 5mm], the air gap between the fifth objective lens and the sixth objective lens ranges from [5mm to 15mm], the center thickness of the sixth objective lens ranges from [0mm to 5mm], the center thickness of the seventh objective lens ranges from [5mm to 10mm], and the air gap between the seventh objective lens and the sensing element in the sight ranges from [5mm to 10mm].

[0024] According to the above scheme, the air gap between the first eyepiece lens and the display element in the sight is in the range of [10mm, 15mm], the center thickness of the first eyepiece lens is in the range of [5mm, 10mm], the center thickness of the second eyepiece lens is in the range of [0mm, 5mm], the air gap between the third eyepiece lens and the second eyepiece lens is in the range of [0mm, 2mm], the center thickness of the third eyepiece lens is in the range of [5mm, 6mm], the air gap between the fourth eyepiece lens and the third eyepiece lens is in the range of [0mm, 1mm], the center thickness of the fourth eyepiece lens is in the range of [5mm, 6mm], the air gap between the fifth eyepiece lens and the fourth eyepiece lens is in the range of [0mm, 1mm], and the center thickness of the fifth eyepiece lens is in the range of [6mm, 7mm].

[0025] According to the above scheme, the fourth objective lens serves as a focusing lens.

[0026] The beneficial effects of the present invention will be explained in conjunction with the embodiments and specific solutions. Attached Figure Description

[0027] Figure 1 This is a structural diagram of an optical system according to an embodiment of the present invention;

[0028] Figure 2 This is an MTF transfer function curve of an objective lens according to an embodiment of the present invention under an object distance of ∞.

[0029] Figure 3 This is an MTF transfer function curve of an objective lens according to an embodiment of the present invention at an object distance of 100m.

[0030] Figure 4 This is an MTF transfer function curve of an objective lens according to an embodiment of the present invention under an object distance of 20m.

[0031] Figure 5 This is an MTF transfer function curve of an objective lens according to an embodiment of the present invention at an object distance of 10m;

[0032] Figure 6 This is an MTF transfer function curve of an objective lens according to an embodiment of the present invention at an object distance of 7m;

[0033] Figure 7 This is a relative illumination diagram of the objective lens according to an embodiment of the present invention;

[0034] Figure 8 This is an eyepiece distortion diagram according to an embodiment of the present invention;

[0035] Figure 9 It is a prior art objective optical system;

[0036] Figure 10 This is a cross-sectional view of a wide-range, low-illuminance aiming scope according to an embodiment of the present invention.

[0037] In the diagram: 1-First objective lens, 2-First cemented objective lens, 3-Fourth objective lens, 4-Fifth objective lens, 5-Second cemented objective lens, 6-First cemented eyepiece lens, 7-Third eyepiece lens, 8-Fourth eyepiece lens, 9-Fifth eyepiece lens, 11-Front objective lens group, 12-Focusing lens group, 13-Objective compensation group, 14-Eyepiece group, 15-Motion mechanism assembly, 16-Display group, 17-Support group, 18-Focusing spring, 19-Main lens body, 20-Screw, 21-Screw, 22-Support screw, 23-Elastic washer. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0039] See Figure 1A wide-range, low-light aiming scope optical system is disclosed, comprising an objective lens optical system and an eyepiece optical system. The objective lens optical system comprises, in sequence from the light incident direction to the light exit direction, a first objective lens 1, a first objective lens cemented lens 2, a fourth objective lens 3, a fifth objective lens 4, and a second objective lens cemented lens 5. The eyepiece optical system comprises, in sequence from the light incident direction to the light exit direction, a first eyepiece cemented lens 6, an eyepiece third lens 7, an eyepiece fourth lens 8, and an eyepiece fifth lens 9.

[0040] Furthermore, in the objective lens optical system, the first objective lens 1 is a plano-convex lens, the first cemented objective lens 2 is formed by cementing the second objective lens and the third objective lens together, the second objective lens is a biconvex lens, the third objective lens is a biconcave lens, the fourth objective lens 3 is a meniscus lens, the fifth objective lens 4 is a biconvex lens, and the second cemented objective lens 5 is formed by cementing the sixth objective lens and the seventh objective lens together, the sixth objective lens is a meniscus lens, and the seventh objective lens is a biconcave lens.

[0041] Furthermore, in the eyepiece optical system, the first cemented eyepiece 6 is formed by cementing the first eyepiece lens and the second eyepiece lens together. The first eyepiece lens is a meniscus lens, the second eyepiece lens is a biconcave lens, the third eyepiece lens 7 is a meniscus lens, the fourth eyepiece lens 8 is a biconvex lens, and the fifth eyepiece lens 9 is a plano-convex lens.

[0042] Furthermore, the material of the first objective lens 1 is heavy phosphorus crown glass, the material of the second objective lens is fluorine crown glass, the material of the third objective lens is heavy lanthanum flint glass, the material of the fourth objective lens 3 is heavy flint glass, the material of the fifth objective lens 4 is heavy flint glass, the material of the sixth objective lens is heavy flint glass, and the material of the seventh objective lens is heavy lanthanum flint glass.

[0043] Furthermore, the first eyepiece lens is made of heavy lanthanum flint glass, the second eyepiece lens is made of heavy flint glass, the third eyepiece lens 7 is made of lanthanum flint glass, the fourth eyepiece lens 8 is made of lanthanum flint glass, and the fifth eyepiece lens 9 is made of heavy lanthanum flint glass.

[0044] The lens glass mentioned above all uses glass materials commonly used by CDGM, which have good processability.

[0045] Furthermore, the dimensions and spacing parameters of each lens in the optical system are shown in the table below:

[0046]

[0047]

[0048] Furthermore, the aforementioned objective optical system has a focal length of 86mm, a working F-number of 1.54, a total length of 114.85mm, a total glass weight of 164.53g, and a matching low-light CMOS detector with a pixel size of 17μm.

[0049] The Pittsval objective is a type of telephoto objective consisting of a positive front group and a negative rear group. It is suitable for objective systems with small field of view and large relative aperture, and can effectively correct spherical aberration and coma. The rear group's cemented doublet is responsible for correcting spherical aberration. When the aperture stop position is fixed, a single cemented doublet cannot simultaneously correct spherical aberration, coma, and field curvature. Therefore, to correct these three aberrations, the positive and negative optical powers of the cemented doublet need to be separated. However, separating the positive and negative optical powers of the cemented doublet cannot correct Pittsval aberrations and will increase astigmatism. Because low-light digital sights operate over a wide wavelength range, stringent requirements are placed on the chromatic aberration correction capabilities of the objective system.

[0050] When focusing a Pittsvald objective lens, the negative lens group is usually selected as the focusing lens group. If a cemented doublet negative lens with separate positive and negative optical power is used as the focusing lens, the increased air gap between the cemented doublets will seriously affect the focusing image quality, causing targets at close distances to be undetectable during focusing.

[0051] Based on the aforementioned existing technology, in this embodiment, the fourth objective lens of the objective optical system is set as a focusing lens. The objective optical system structure adopts a Pittsvald objective lens as the initial structure, which is then transformed into a "positive group + focusing negative group + compensation group" structure (the rear cemented doublet lens is split into two cemented doublet lenses, and the positive and negative optical powers of one cemented doublet lens are separated, with the separated negative lens serving as the focusing lens, and the other cemented doublet lens fixed as the compensation aberration group). If an overall focusing scheme is used, during the focusing process, due to the fit gap between the lens barrel and the objective lens group, there is an off-center angle between the actual optical axis and the theoretical optical axis, and this off-center angle will affect all optical components. Therefore, this objective optical system adopts a single negative lens internal focusing scheme, because the off-center angle generated by focusing will only affect the focusing lens group, which can achieve better optical axis stability, a smooth focusing operation, and reduce the weight of the focusing group, which is conducive to achieving product lightweighting. The focusing frame has a length-to-diameter ratio of 1.08:1, which effectively reduces the eccentricity caused by the lens's gravity and dimensional tolerances during focusing. The focusing lens moves along the optical axis from the first objective lens to the second cemented objective lens. The focusing distance is 0.83mm from 10m to infinity and 1.23mm from 7m to infinity. During focusing, the theoretical MTF at the image plane position is greater than 0.4 at the cutoff frequency, and the image quality remains stable and clear throughout the entire focusing process.

[0052] Furthermore, the eyepiece optical system has a focal length of 24.5mm, an exit pupil diameter of 6mm, an exit pupil distance of 50mm, a total length of 40.72mm, and a total glass weight of 89.97g. It is matched with a 0.6-inch display screen. The distortion of the eyepiece optical system is less than 0.5% (see...). Figure 8 ).

[0053] The objective lens MTF transfer function curves at various focusing distances are as follows: Figures 2-6 As shown, the image quality of the objective lens remains clear and stable during focusing at object distances from 7m to ∞, without drastic changes as the focusing lens moves.

[0054] Compared with existing technologies and similar products, the beneficial effects of the present invention are:

[0055] 1. The objective lens has a viewing distance range of 7m to ∞, with clear image quality across the entire viewing distance. The wide viewing distance range allows users to clearly observe targets at different distances. The internal focusing method gives the rifle sight system good waterproofness, airtightness, and optical axis stability.

[0056] 2. The aperture of the positive group glass of the objective lens is limited, which reduces the overall mass of the optical system and adjusts the center of gravity of the optical system, solving the problem of the fit between the objective lens connector and the objective lens group under the conditions of shock and vibration in the use of the gun sight system.

[0057] 3. The eyepiece has a maximum distortion of 0.5% across the entire field of view, resulting in excellent image quality across the entire field of view;

[0058] 4. The entire optical system has a simple structure, uses common glass materials and highly machinable surfaces, and achieves lightweight design.

[0059] See Figure 7 The objective lens optical system has a relative illumination of more than 90% across the entire field of view and a vignetting of less than 7% at the edge of the objective lens, ensuring sufficient light transmission at the edge of the field of view.

[0060] See Figure 9 The objective optical system of the prior art has similar specifications to the objective optical system of the present invention. The parameters of the two are compared in the table below:

[0061] parameter This embodiment Existing technology focal length 86mm 85.8mm F / # 1.54 1.45 weight 164.53g 240.19g View range 7m～∞ 10m～∞ Focusing distance 1.23mm 0.9mm Focusing method Internal focusing of a single negative lens Internal focusing of a single negative lens Matching detector pixel size 17μm 17μm

[0062] As can be seen from the above parameters, the center of gravity of the objective lens optical system in the prior art is significantly far from the detector, resulting in poor vibration resistance. In this embodiment, the center of gravity of the objective lens glass is shifted rearward towards the detector end compared to the objective lens in the prior art, making the overall optical system closer to the detector and improving the reliability of the digital rifle sight. In this embodiment, the center of gravity of the objective lens falls between the first cemented lens and the fourth lens, resulting in a more rational optical lens arrangement. In summary, the objective lens of this invention exhibits superior performance in terms of lightweight design, viewing range, and vibration resistance.

[0063] See Figure 10 This embodiment also discloses a sight adapted to the above-mentioned optical system, the specific structure of which is as follows:

[0064] The scope includes a front objective lens group 11, a focusing lens group 12, an objective lens compensation group 13, an eyepiece group 14, a mechanism assembly 15, a display group 16, a support group 17, a focusing spring 18, a main body 19, a locking screw 20, a screw 21, a support screw 22, and a spring washer 23. The objective lens compensation group 13 is screwed into the corresponding thread on the main body 19 after being coated with adhesive. The focusing lens group 12 is ground and then installed into the main body 19. A focusing spring 18 is provided between the focusing lens group 12 and the objective lens compensation group 13 to eliminate the gap between the focusing lens group 12 and the main body 19 during focusing. The front objective lens group 11 is individually sealed and nitrogen-filled. After being coated with adhesive, it is screwed into the front of the main body 19 and secured with a locking screw 20 to prevent loosening and falling off. The mechanism assembly 15 is secured to the top of the main body 19 from the rear using four screws 21 (made of TC4 titanium alloy) after being coated with adhesive. After the display assembly 15 and the left end face of the eyepiece assembly 16 are attached, they are locked with screws 21 to complete the assembly of the eyepiece assembly 14. The eyepiece assembly 14 is locked to the main scope body 19 with four screws 21 (high-strength screws). The support body 17 is attached to the lower part of the main scope body 19. An elastic washer 23 is provided between the support screw 22 and the support body 17. The support assembly 17 is screwed into the two threaded holes on the lower part of the main scope body 19 after applying glue to two high-strength screws 22. The elastic washer 23 can effectively prevent the support body from loosening due to large impacts during the use of the scope, which would cause the scope to malfunction.

[0065] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A wide-range, low-light aiming scope optical system, characterized in that: The optical system includes an objective lens optical system and an eyepiece optical system; The objective lens optical system includes a first objective lens, a first cemented objective lens, a fourth objective lens, a fifth objective lens, and a second cemented objective lens arranged sequentially from the light incident direction to the light exit direction; the eyepiece optical system includes a first cemented eyepiece, a third eyepiece, a fourth eyepiece, and a fifth eyepiece arranged sequentially from the light incident direction to the light exit direction. In the objective lens optical system, the first objective lens is a plano-convex lens, the first cemented objective lens is formed by cementing the second and third objective lenses together, the second objective lens is a biconvex lens, the third objective lens is a biconcave lens, the fourth objective lens is a meniscus lens, the fifth objective lens is a biconvex lens, and the second cemented objective lens is formed by cementing the sixth and seventh objective lenses together, the sixth objective lens is a meniscus lens, and the seventh objective lens is a biconcave lens. In the eyepiece optical system, the first cemented eyepiece is formed by cementing the first eyepiece lens and the second eyepiece lens together. The first eyepiece lens is a meniscus lens, the second eyepiece lens is a biconcave lens, the third eyepiece lens is a meniscus lens, the fourth eyepiece lens is a biconvex lens, and the fifth eyepiece lens is a plano-convex lens. The radius of curvature of the side of the first objective lens furthest from the second objective lens is taken as: The radius of curvature of the side of the first objective lens closest to the second objective lens is infinite. The radius of curvature of the side of the second objective lens furthest from the third objective lens is taken as: The radius of curvature of the side of the second objective lens closest to the third objective lens is taken as... ; The radius of curvature of the side of the third objective lens furthest from the second objective lens is taken as: ; The radius of curvature of the side of the fourth objective lens furthest from the fifth objective lens is taken as... The radius of curvature of the side of the fourth objective lens closest to the fifth objective lens is taken as... ; The radius of curvature of the side of the fifth objective lens furthest from the sixth objective lens is taken as: The radius of the side of the fifth objective lens closest to the sixth objective lens is taken as [value missing]. ; The radius of curvature of the side of the sixth objective lens furthest from the seventh objective lens is taken as... The radius of curvature of the side of the sixth objective lens closest to the seventh objective lens is taken as... ; The radius of curvature of the side of the seventh objective lens furthest from the sixth objective lens is taken as: ; The center thickness of the first objective lens is within the range of values. The range of values ​​for the air gap between the first objective lens and the second objective lens The center thickness of the second objective lens ranges from [value missing]. The center thickness of the third objective lens ranges from [value missing]. The air gap between the third objective lens and the fourth objective lens has a range of values. The center thickness of the fourth objective lens is within the range of [value missing]. The air gap between the fourth objective lens and the fifth objective lens has a range of values. The center thickness of the fifth objective lens ranges from [value missing]. The air gap between the fifth objective lens and the sixth objective lens has a range of values. The center thickness of the sixth objective lens ranges from [value missing]. The center thickness of the seventh objective lens ranges from [value missing]. The air gap between the seventh objective lens and the sensing element in the sight ranges from [value missing]. .

2. The wide-range, low-light aiming scope optical system according to claim 1, characterized in that: The first objective lens is made of heavy phosphorus crown glass, the second objective lens is made of fluorine crown glass, the third objective lens is made of heavy lanthanum flint glass, the fourth objective lens is made of heavy flint glass, the fifth objective lens is made of heavy flint glass, the sixth objective lens is made of heavy flint glass, and the seventh objective lens is made of heavy lanthanum flint glass.

3. The wide-range, low-illuminance aiming scope optical system according to claim 1, characterized in that: The first eyepiece lens is made of heavy lanthanum flint glass, the second eyepiece lens is made of heavy flint glass, the third eyepiece lens is made of lanthanum flint glass, the fourth eyepiece lens is made of lanthanum flint glass, and the fifth eyepiece lens is made of heavy lanthanum flint glass.

4. The wide-range, low-light aiming scope optical system according to claim 1, characterized in that: The radius of curvature of the side of the first eyepiece lens furthest from the second eyepiece lens is taken as: The radius of curvature of the side of the first eyepiece lens closest to the second eyepiece lens is taken as... ; The radius of curvature of the side of the second eyepiece lens closest to the third eyepiece lens is infinite. The radius of curvature of the side of the third eyepiece lens furthest from the fourth eyepiece lens is taken as: The radius of curvature of the side of the third eyepiece closest to the fourth eyepiece is taken as: ; The radius of curvature of the side of the fourth eyepiece lens furthest from the fifth eyepiece lens is infinite, while the radius of curvature of the side of the fourth eyepiece lens closest to the fifth eyepiece lens is [value missing]. ; The radius of curvature of the side of the fifth eyepiece closest to the fourth eyepiece is taken as: The radius of curvature of the side of the fifth eyepiece lens that is far from the fourth eyepiece lens is infinite.

5. The wide-range, low-illuminance aiming scope optical system according to claim 4, characterized in that: The range of values ​​for the air gap between the first lens of the eyepiece and the display element in the scope is: The center thickness of the first lens of the eyepiece is within the range of... The center thickness of the second lens of the eyepiece is within the range of... The air gap between the third eyepiece lens and the second eyepiece lens has a range of values. The center thickness of the third lens of the eyepiece is within the range of... The air gap between the fourth eyepiece lens and the third eyepiece lens has a range of values. The center thickness of the fourth lens of the eyepiece is within the range of [value missing]. The air gap between the fifth eyepiece lens and the fourth eyepiece lens is The center thickness of the fifth lens of the eyepiece is within the range of [value missing]. .

6. The wide-range, low-light aiming scope optical system according to claim 1, characterized in that: The fourth lens of the objective lens serves as a focusing lens.

Images