Optical system of glass-plastic mixed eyepiece

Abstract

The invention provides an optical system of a glass-plastic mixed eyepiece. The optical system comprises a view field diaphragm, a field lens, a double-glue lens and an aperture diaphragm which are sequentially arranged from an image space to an object space, wherein the field lens is a plastic lens, and the double-glue lens is a glass double-glue lens. The optical system is simple in structure, light in weight and low in production cost.

Description

Technical Field

[0001] The invention relates to the technical field of gun aiming, and in particular to an optical system of a glass-plastic hybrid eyepiece. Background Art

[0002] At present, the development of digital gun sights is very rapid, and the functions are becoming more and more powerful. The requirements for parameters such as pupil diameter, pupil distance, and magnification are also getting higher and higher. To design eyepieces that meet these requirements, the use of traditional spherical lenses not only requires high material costs, but also requires a large amount of glass and is also heavy, and the production cost is high when processing in large quantities. Summary of the invention

[0003] The object of the present invention is to provide an optical system of a glass-plastic hybrid eyepiece to reduce the weight and production cost of the eyepiece.

[0004] In order to solve the above technical problems, the present invention provides an optical system of a glass-plastic hybrid eyepiece, comprising a field stop, a field lens, a double-gel lens, and an aperture stop arranged in sequence from the image side to the object side; wherein the field lens is a plastic lens, and the double-gel lens is a glass double-gel lens. According to the above scheme, the field lens has positive focal power; the double glue lens is formed by gluing the second lens of the eyepiece and the third lens of the eyepiece, which are arranged in sequence from the image side to the object side. The second lens of the eyepiece has positive focal power, and the third lens of the eyepiece has negative focal power.

[0005] According to the above scheme, the focal length fa of the field lens satisfies: 73.091mm≤fa≤81.785mm; The focal length fb of the double-gel lens satisfies: 50.16mm≤fb≤58.8mm; The focal length fb1 of the second lens of the eyepiece satisfies: 19.858mm≤fb1≤22.727mm; The focal length fb2 of the second lens of the eyepiece satisfies: 28.282mm≤fb≤31.258mm.

[0006] According to the above scheme, the air gap between the field aperture and the field lens is 17.155mm~17.165mm.

[0007] According to the above scheme, the air gap between the field mirror and the double-gel lens is 0.4mm~0.6mm.

[0008] According to the above scheme, the field lens is an aspherical lens made of ACRYLIC material.

[0009] The present invention also provides a glass-plastic hybrid eyepiece, comprising an eyepiece joint, an eyepiece frame, an eyepiece pressure ring, an eyepiece spacer, a field lens, and a double-gel lens; The eyepiece frame is arranged in the eyepiece joint, and the eyepiece frame can move axially in the eyepiece joint; The field lens and the double-gel lens are fixed in the eyepiece frame by an eyepiece pressing ring, and the eyepiece spacer is arranged between the field lens and the double-gel lens; the field lens is a plastic lens, and the double-gel lens is a glass double-gel lens.

[0010] According to the above scheme, the front end of the eyepiece joint is connected to the shell threaded flange through threads, and the shell threaded flange and the eyepiece joint are fixed by a locking screw.

[0011] According to the above scheme, an outer sealing ring of the objective lens is arranged between the threaded flange of the outer shell and the eyepiece joint; a rear sealing ring of the eyepiece is arranged between the eyepiece pressure ring and the field lens; an outer sealing ring of the eyepiece frame is arranged between the eyepiece frame and the eyepiece joint; a diopter adjustment ring is connected to the rear end of the eyepiece frame through a thread; and a front sealing ring of the eyepiece is arranged between the diopter locking ring and the double-gel lens.

[0012] According to the above scheme, the rear end of the eyepiece frame is connected with a diopter locking ring through a thread.

[0013] Beneficial Effects The optical system of the present invention uses plastic lenses, which effectively reduces the overall weight and manufacturing cost of the optical system, is conducive to the lightweight of the eyepiece, and can reduce the cost of mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic structural diagram of a glass-plastic hybrid eyepiece according to a second embodiment of the present invention; Figure 2 1 is a schematic diagram of the optical system structure of the glass-plastic hybrid eyepiece according to the first embodiment of the present invention; Figure 3 is a point diagram of the optical system of the glass-plastic hybrid eyepiece according to the first embodiment of the present invention; Figure 4 This is a field curvature distortion diagram of the optical system of the glass-plastic hybrid eyepiece according to the first embodiment of the present invention; Figure 5 This is the MTF diagram of the optical system of the glass-plastic hybrid eyepiece according to the first embodiment of the present invention.

[0015] In the figure: 1-eyepiece frame, 2-eyepiece joint, 3-diopter adjustment ring, 4-diopter locking ring, 5-stop ring, 6-shell threaded flange, 7-objective lens outer sealing ring, 8-locking screw, 9-eyepiece pressure ring, 10-eyepiece rear sealing ring, 11-eyepiece first lens, 12-eyepiece spacer, 13-cemented lens, 14-eyepiece front sealing ring, 15-eyepiece frame outer sealing ring. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0017] Embodiment 1: See also Figure 2 This embodiment discloses an optical system of a glass-plastic hybrid eyepiece, including a field stop, a field lens 11, a double-gel lens 13, and an aperture stop, which are arranged in sequence from the image side to the object side; wherein the field lens 11 is a plastic lens, and the double-gel lens 13 is a glass double-gel lens 13.

[0018] Furthermore, the field lens 11 has positive focal power; the double glue lens 13 is formed by gluing the second eyepiece lens and the third eyepiece lens arranged in sequence from the image side to the object side, the second eyepiece lens has positive focal power, and the third eyepiece lens has negative focal power.

[0019] Further, the focal length fa of the field lens 11 satisfies: 73.091 mm ≤ fa ≤ 81.785 mm; The focal length fb of the double-gel lens 13 satisfies: 50.16 mm ≤ fb ≤ 58.8 mm; The focal length fb1 of the second lens of the eyepiece satisfies: 19.858mm≤fb1≤22.727mm; The focal length fb2 of the second lens of the eyepiece satisfies: 28.282mm≤fb≤31.258mm.

[0020] Furthermore, the air gap between the field aperture and the field lens 11 is 17.161 mm.

[0021] Furthermore, the air gap between the field lens 11 and the doublet lens 13 is 0.5 mm.

[0022] Furthermore, the field lens 11 is an aspherical lens, and the material is ACRYLIC.

[0023] The specific parameters of the optical system of this embodiment are shown in the following table: Table 1 Optical system parameters of glass-plastic hybrid eyepiece

[0024] Among them, the aspheric coefficient is calculated according to the even aspheric formula

[0025] Where r is the aperture in the direction perpendicular to the optical axis, z is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of r along the optical axis, c is the vertex curvature radius of the surface, k is the cone coefficient, a is the high-order aspheric coefficient, see the table below, and i is the aspheric order.

[0026] Table 2 Aspheric coefficients 1

[0027] Table 3 Aspheric coefficient 2

[0028] The optical system of this embodiment has a center MTF>0.85@20lp / mm, an edge MTF>0.3@20lp / mm, a total length of 35.66mm, a compact structure, and a simple appearance. Figure 3~Figure 5 .

[0029] Embodiment 2: See also Figure 1 , based on the first embodiment, this embodiment discloses a glass-plastic hybrid eyepiece, including an eyepiece joint 2, an eyepiece frame 1, an eyepiece pressure ring 9, an eyepiece spacer 12, a field lens 11, and a double-gel lens 13; The eyepiece frame 1 is disposed in the eyepiece joint 2, and the eyepiece frame 1 can move axially in the eyepiece joint 2; The field lens 11 and the doublet lens 13 are fixed in the eyepiece frame 1 by the eyepiece pressing ring 9 , and the eyepiece spacer 12 is arranged between the field lens 11 and the doublet lens 13 .

[0030] Furthermore, the front end of the eyepiece joint 2 is connected to a shell threaded flange 6 via a thread, and the shell threaded flange 6 and the eyepiece joint 2 are fixed via a locking screw 8 .

[0031] Furthermore, an objective lens outer sealing ring 7 is provided between the housing threaded flange 6 and the eyepiece joint 2 .

[0032] Furthermore, an eyepiece rear sealing ring 10 is provided between the eyepiece pressure ring 9 and the field lens 11 .

[0033] Furthermore, an eyepiece frame outer sealing ring 15 is provided between the eyepiece frame 1 and the eyepiece joint 2 .

[0034] Furthermore, a diopter adjustment ring 3 is threadedly connected to the rear end of the eyepiece frame 1 .

[0035] Furthermore, a stop ring 5 is threadedly connected to the rear end of the eyepiece joint 2 to prevent the eyepiece frame 1 from being screwed out of the eyepiece joint 2 .

[0036] Furthermore, a diopter locking ring 4 is threadedly connected to the rear end of the eyepiece frame 1, and the diopter locking ring 4 is used to connect the eyepiece cover.

[0037] Furthermore, an eyepiece front sealing ring 14 is provided between the diopter locking ring 4 and the double-gel lens 13 .

[0038] The magnification of the glass-plastic hybrid eyepiece of this embodiment is 11.5×, the pupil distance is 40mm, the pupil diameter is 5mm, the diopter adjustment range is ±5SD, and the entire eyepiece moves 0.47mm when adjusting 1SD. The glass-plastic hybrid eyepiece of this embodiment has the characteristics of light weight, long pupil, large aperture, high image quality, stable image plane, easy processing and assembly, and convenient use.

[0039] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0040] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An optical system of a glass-plastic hybrid eyepiece, characterized in that: It includes a field stop, a field lens, a double-gel lens, and an aperture stop which are arranged in sequence from the image side to the object side; The field lens is a plastic lens and the double-gel lens is a glass double-gel lens.

2. The optical system of the glass-plastic hybrid eyepiece according to claim 1, characterized in that: The field lens has positive focal power; the double glue lens is formed by gluing the second lens of the eyepiece and the third lens of the eyepiece, which are arranged in sequence from the image side to the object side. The second lens of the eyepiece has positive focal power, and the third lens of the eyepiece has negative focal power.

3. The optical system of the glass-plastic hybrid eyepiece according to claim 2, characterized in that: The focal length fa of the field lens satisfies: 73.091mm≤fa≤81.785mm; The focal length fb of the double-gel lens satisfies: 50.16mm≤fb≤58.8mm; The focal length fb1 of the second lens of the eyepiece satisfies: 19.858mm≤fb1≤22.727mm; The focal length fb2 of the second lens of the eyepiece satisfies: 28.282mm≤fb≤31.258mm.

4. The optical system of the glass-plastic hybrid eyepiece according to claim 1 or 2, characterized in that: The air gap between the field aperture and the field lens is 17.155mm~17.165mm.

5. The optical system of the glass-plastic hybrid eyepiece according to claim 1 or 2, characterized in that: The air gap between the field mirror and the double-gel lens is 0.4mm~0.6mm.

6. The optical system of the glass-plastic hybrid eyepiece according to claim 1, characterized in that: The field lens is an aspherical lens made of ACRYLIC material.

7. A glass-plastic hybrid eyepiece, characterized in that: Including eyepiece joint, eyepiece frame, eyepiece pressure ring, eyepiece spacer, field lens, double glue lens; The eyepiece frame is arranged in the eyepiece joint, and the eyepiece frame can move axially in the eyepiece joint; The field lens and the double-gel lens are fixed in the eyepiece frame by an eyepiece pressing ring, and the eyepiece spacer is arranged between the field lens and the double-gel lens; the field lens is a plastic lens, and the double-gel lens is a glass double-gel lens.

8. The glass-plastic hybrid eyepiece according to claim 7, characterized in that: The front end of the eyepiece joint is connected with a shell threaded flange through a thread, and the shell threaded flange and the eyepiece joint are fixed through a locking screw.

9. The glass-plastic hybrid eyepiece according to claim 7, characterized in that: An objective lens outer sealing ring is arranged between the outer shell threaded flange and the eyepiece joint; an eyepiece rear sealing ring is arranged between the eyepiece pressure ring and the field lens; an eyepiece frame outer sealing ring is arranged between the eyepiece frame and the eyepiece joint; a diopter adjustment ring is connected to the rear end of the eyepiece frame through a thread; and an eyepiece front sealing ring is arranged between the diopter locking ring and the double-gel lens.

10. The glass-plastic hybrid eyepiece according to claim 7, characterized in that: The rear end of the eyepiece frame is connected with a diopter locking ring through threads.

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