Compact continuous zoom eyepiece

Abstract

The utility model discloses a compact continuous zoom eyepiece, which comprises an eyepiece sleeve, an eyepiece joint, a zoom hand wheel, a switching circuit board group, a display screen group, an image rotation lens group and an eyepiece group, the eyepiece joint is respectively connected with an external sighting telescope body and an eyepiece sleeve; the display screen group comprises a display screen, a display screen circuit board and a display screen frame; the switching circuit board group is fixed in the eyepiece connector, and the display screen group is fixed in the front end of the relay lens group; the front end and the rear end of the image rotation lens group are fixed to the eyepiece connector and the eyepiece sleeve respectively, the image rotation lens group comprises an image rotation lens tube, a zoom tube, a first focusing lens group, a second focusing lens group and a third focusing lens group, and the zoom hand wheel is arranged on the outer side of the eyepiece sleeve in a sleeving mode and is in transmission connection with the first focusing lens group and the second focusing lens group; the eyepiece group is connected to the rear end of the eyepiece sleeve. According to the eyepiece, zoom adjustment of a traditional white light sighting telescope is fused to a digital sighting telescope, and zoom operation of a user is facilitated.

Description

TECHNICAL FIELD

[0001] The utility model relates to sighting telescope technical field, concretely relates to a compact continuous zoom eyepiece. BACKGROUND

[0002] At present, the digital gun sighting telescope develops very fast, and the function is more and more powerful. As the basic function of gun sighting telescope, digital gun sighting telescope usually controls electronic magnification by adjusting function menu, realizes the magnification observation to target image. And for traditional white light sighting telescope, directly rotates zoom hand wheel, realizes the adjustment of magnification. It can be known by comparison that the digital gun sighting telescope is complicated in operation in realizing the zoom function, and it deviates from the traditional use habit, and brings many inconvenience to users. SUMMARY

[0003] The utility model discloses a compact continuous zoom eyepiece, which combines the traditional zoom hand wheel with the digital sighting telescope, and is convenient for the zoom operation of users.

[0004] To solve the above technical problems, the utility model provides a compact continuous zoom eyepiece, which comprises: an eyepiece barrel, an eyepiece joint, a display screen group, a zoom hand wheel, an adapter circuit board group, an image conversion lens group and an eyepiece group.

[0005] The eyepiece joint is connected with the sighting telescope lens body and the eyepiece barrel outside.

[0006] The display screen group comprises a display screen, a display screen circuit board and a display screen frame. The adapter circuit board group is fixed in the eyepiece joint, and the display screen group is fixed in the front end of the image conversion lens group.

[0007] The front and rear ends of the image conversion lens group are fixed to the eyepiece joint and the eyepiece barrel respectively. The image conversion lens group comprises an image conversion lens tube, a zoom tube, a first focusing lens group, a second focusing lens group and a third focusing lens group. The zoom hand wheel is sleeved outside the eyepiece barrel and is in transmission connection with the first focusing lens group and the second focusing lens group.

[0008] The eyepiece group is connected to the rear end of the eyepiece barrel.

[0009] According to the above scheme, the first focusing lens group comprises a first focusing lens and a first focusing lens frame. The second focusing lens group comprises a second focusing lens and a second focusing lens frame. The third focusing lens group comprises a field lens and a third focusing lens frame.

[0010] The field lens is fixed to the third focusing lens frame, and the third focusing lens frame is fixed to the front end of the image conversion lens tube.

[0011] The image conversion lens tube is provided with a straight groove on the side surface.

[0012] The zoom tube is sleeved outside the image transfer lens tube, and the zoom tube is axially limited by the front end of the transfer lens tube and the zoom tube pressure ring; a first curved groove and a second curved groove are provided on the side of the zoom tube;

[0013] The first focusing lens and the second focusing lens are fixed in the first focusing lens frame and the second focusing lens frame respectively. The first focusing lens frame and the second focusing lens frame are axially slidable in the image transfer lens tube. The first focusing lens frame and the second focusing lens frame are connected to the outside of each of the first focusing lens frame and the second focusing lens frame. The outer ends of the sliding screws pass through the straight groove of the image transfer lens tube and are respectively located in the first curved groove and the second curved groove of the magnification tube.

[0014] A zoom slot with a certain opening angle is provided on the side of the eyepiece barrel. The outer end of the zoom rotating screw is fixed to the zoom handwheel, and the inner end of the zoom rotating screw passes through the zoom slot of the eyepiece barrel and is connected to the zoom tube.

[0015] According to the above solution, a gasket is provided between the end of the relay lens tube and the end of the magnification tube.

[0016] According to the above solution, the maximum rise angle of the first curved groove and the second curved groove is 35.5°.

[0017] According to the above scheme, the eyepiece assembly is connected to the eyepiece barrel through a multi-start thread.

[0018] According to the above solution, a backstop ring is connected to the rear end of the eyepiece tube.

[0019] According to the above scheme, the optical system of the compact continuous zoom eyepiece includes a field stop, a field lens, a first focusing lens group, a second focusing lens group, and an eyepiece group optical system arranged in sequence from the display screen to the human eye;

[0020] The first focusing lens group is formed by gluing together a first focusing lens with positive focal power, a second focusing lens with negative focal power, and a third focusing lens with positive focal power, which are arranged in sequence from the display screen to the human eye;

[0021] The second focusing lens group includes a fourth focusing lens with positive focal length, a fifth focusing lens with positive focal length, and a sixth focusing lens with positive focal length, which are sequentially arranged from the display screen to the human eye;

[0022] The eyepiece optical system includes a first eyepiece lens with negative optical power, a second eyepiece lens with positive optical power, a third eyepiece lens with positive optical power, and a fourth eyepiece lens with positive optical power, which are arranged in sequence from the display screen to the human eye.

[0023] According to the above scheme, all lenses in the optical system of the compact continuous zoom eyepiece are made of glass material.

[0024] According to the above scheme, the focal length fa of the field lens satisfies: 1047.93mm≤fa≤1069.11mm;

[0025] The focal length fb of the first focusing lens group satisfies: 57.45mm≤fb≤63.49mm;

[0026] The focal length fc of the second focusing lens group satisfies: 18.28mm≤fc≤20.20mm;

[0027] The focal length fd of the eyepiece group optical system satisfies: 21.52mm≤fd≤23.78mm;

[0028] The eyepiece first lens and the eyepiece second lens are cemented to form an eyepiece cemented lens, and the focal length fe of the eyepiece cemented lens satisfies: 93.2mm≤fe≤95.08mm.

[0029] According to the above scheme, the air gap between the field stop and the field lens is 9.01mm;

[0030] The variable air gap range between the field lens and the first focusing lens group is 1.82mm~14.5mm;

[0031] The variable air gap between the first focusing lens group and the second focusing lens group is 0.25mm~4.4mm;

[0032] The variable air gap between the second focusing lens group and the eyepiece group optical system is 27.92mm~15.65mm;

[0033] The image of the relay lens group is formed on the vergence adjustment image surface, and the vergence adjustment image surface and the field stop are conjugate surfaces; and the air gap between the vergence adjustment image surface and the eyepiece group optical system is 12.8mm.

[0034] Advantageous effects

[0035] The variable magnification mode of the utility model is more in line with the use habit of the user, and the use convenience of the sighting telescope is improved. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is the explosion schematic view of the compact continuous variable magnification eyepiece of one embodiment of the utility model;

[0037] Figure 2 is the perspective view of the compact continuous variable magnification eyepiece of one embodiment of the utility model;

[0038] Figure 3 is the cross-sectional view of the compact continuous variable magnification eyepiece of one embodiment of the utility model;

[0039] Figure 4This is an optical system diagram of a compact continuous zoom eyepiece according to an embodiment of the present invention at a high magnification of 19.8×;

[0040] Figure 5 This is a diagram of vertical axis chromatic aberration of a compact zoom eyepiece according to an embodiment of the present invention at a high magnification of 19.8×;

[0041] Figure 6 This is an MTF diagram of the compact zoom eyepiece at a high magnification of 19.8× according to an embodiment of the present invention;

[0042] Figure 7 This is a diagram of the distortion field curvature of the compact zoom eyepiece of one embodiment of the present invention at a high magnification of 19.8×;

[0043] Figure 8 This is an optical system diagram of a compact continuous zoom eyepiece according to an embodiment of the present invention at a low magnification of 6.6×;

[0044] Figure 9 This is a diagram of vertical axis chromatic aberration of a compact zoom eyepiece according to an embodiment of the present invention at a low magnification of 6.6×;

[0045] Figure 10 This is an MTF diagram of the compact zoom eyepiece at a low magnification of 6.6× according to an embodiment of the present invention;

[0046] Figure 11 This is a diagram of the distortion field curvature of the compact zoom eyepiece of one embodiment of the utility model at a low magnification of 6.6×;

[0047] Figure 12 This is a schematic diagram of the display screen group adjustment state of one embodiment of the present utility model;

[0048] Figure 13 This is a schematic diagram of the connection between a compact continuous zoom eyepiece and an external sighting scope body according to one embodiment of the present invention.

[0049] In the figure: 1-eyepiece assembly, 2-image transfer lens assembly, 3-display screen assembly, 4-adapter circuit board assembly, 5-eyepiece connector, 6-eyepiece barrel, 7-display screen adjustment ring, 8-zoom handwheel, 9-image transfer assembly pressure ring, 10-stop ring, 11-diopter adjustment ring, 12-zoom rotation screw, 13-first sealing ring, 14-second sealing ring, 15-first tightening screw, 16-screw, 17-second tightening screw. DETAILED DESCRIPTION

[0050] To make the purpose, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying 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.

[0051] See also Figures 1 to 3 This embodiment provides a compact continuous zoom eyepiece, comprising: an eyepiece barrel 6, an eyepiece connector 5, a zoom hand wheel 8, an adapter circuit board group 4, a display screen group 3, a transfer lens group 2, and an eyepiece group 1;

[0052] The eyepiece connector 5 is connected to the external sight body and the eyepiece barrel (see Figure 13 , the eyepiece connector 5 is connected to the sight body through an internal thread and is connected to the eyepiece barrel 6 through an external thread);

[0053] The display screen group 3 includes a display screen, a display screen circuit board, and a display screen frame; the adapter circuit board group 4 is fixed in the eyepiece joint 5, and the display screen group 3 is fixed in the front end of the image transfer lens group 2;

[0054] The front and rear ends of the image transfer lens group 2 are fixed to the eyepiece joint 5 and the eyepiece barrel 6 respectively. The image transfer lens group 2 includes an image transfer lens tube, a magnification tube, a first focus lens group, a second focus lens group, and a third focus lens group. The magnification hand wheel 8 is sleeved on the outside of the eyepiece barrel 6 and is in transmission connection with the first focus lens group and the second focus lens group.

[0055] The eyepiece assembly 1 is connected to the rear end of the eyepiece barrel 6 .

[0056] Furthermore, the rear end of the eyepiece connector 5 is inserted into the front end of the eyepiece barrel 6 , and the eyepiece connector 5 and the eyepiece barrel 6 are fixed by a first tightening screw 15 .

[0057] Furthermore, a first sealing ring 13 is provided between the eyepiece joint 5 and the eyepiece barrel 6 .

[0058] Furthermore, a square groove bottom surface is provided in the eyepiece joint 5 , and the adapter circuit board assembly 4 is fixed to the square groove bottom surface by screws 16 .

[0059] Furthermore, the relay lens assembly 2 is fixed to the rear end surface of the eyepiece joint 5 by means of screws 16 .

[0060] Furthermore, the steering lens group includes a steering lens tube, a zoom tube, a first focusing lens group, a second focusing lens group, and a third focusing lens group;

[0061] The field lens is fixed to the third focusing lens frame through a pressing ring;

[0062] A straight groove is provided on the side of the image-relay lens tube;

[0063] The zoom tube is sleeved outside the image-shifting lens tube, and the zoom tube is axially limited by the front end of the steering lens tube and the zoom tube pressure ring. The image-shifting group pressure ring 9 is fixed to the rear end of the steering lens tube. The side of the zoom tube is provided with a first curved groove and a second curved groove.

[0064] The first focusing lens and the second focusing lens are fixed in the first focusing lens frame and the second focusing lens frame respectively. The first focusing lens frame and the second focusing lens frame are axially slidable in the image transfer lens tube. The first focusing lens frame and the second focusing lens frame are connected to the outside of each of the first focusing lens frame and the second focusing lens frame. The outer ends of the sliding screws pass through the straight groove of the image transfer lens tube and are respectively located in the first curved groove and the second curved groove of the magnification tube.

[0065] A zoom slot with a certain opening angle is provided on the side of the eyepiece barrel 6. The outer end of the zoom rotating screw 12 is fixed to the zoom handwheel 8, and the inner end of the zoom rotating screw 12 passes through the zoom slot of the eyepiece barrel 6 and is connected to the zoom tube.

[0066] The magnification principle is as follows: turn the magnification handwheel 8, the magnification handwheel 8 drives the magnification rotating screw 12 to move in the magnification slot of the eyepiece barrel 6, and the magnification rotating screw 12 drives the magnification tube to rotate, so that the sliding screws in the first curved slot and the second curved slot respectively drive the first focusing lens frame and the second focusing frame to move axially along the straight slot of the image transfer lens tube, thereby changing the magnification of the eyepiece imaging, and the user can observe the magnified display screen image at one end of the eyepiece group 1.

[0067] Furthermore, a washer is provided between the end of the image-transmitting lens tube and the end of the zoom tube. The washer is made of copper, which can make the rotation between the image-transmitting lens tube and the zoom tube smoother, optimize the zoom feel, and increase the wear resistance between the structural parts.

[0068] Furthermore, the maximum rise angle of the first curved groove and the second curved groove is 35.5°, ensuring smooth movement and comfortable hand feel during the zoom process.

[0069] Furthermore, the rear end of the steering lens group is fastened in the eyepiece barrel 6 by the steering lens group pressure ring 9, the steering lens group pressure ring 9 is threadedly connected to the eyepiece barrel 6, and the steering lens group pressure ring 9 and the eyepiece barrel 6 are fastened by a second tightening screw 17.

[0070] Furthermore, a second sealing ring 14 is provided between the zoom hand wheel 8 and the eyepiece barrel 6 to ensure airtightness and optimize the rotation feel of the zoom hand wheel 8 .

[0071] Furthermore, the compact zoom eyepiece also includes a display screen adjustment mechanism, which includes a display screen adjustment ring 7 provided on the front and rear sides of the display screen, with a plurality of adjustment holes provided on the side of the display screen adjustment ring 7. The display screen adjustment ring 7 is threadedly connected to the front end of the image transfer lens tube, and the side of the image transfer lens tube is provided with an adjustment notch; a guide block is provided at the front end of the steering lens group, and a guide groove is provided on the end surface of the display screen, and the guide groove and the guide block are precisely matched;

[0072] The adjustment process of the display screen is as follows: When the display screen is in the adjustment state, the eyepiece tube 6 is not installed. Figure 12 At this time, the display adjustment rings 7 on both sides of the display screen are rotated by adjusting the notches and adjustment holes, so that the display adjustment rings 7 drive the display screen to move axially along the guide blocks (the horizontal tilt angle of the display screen can always meet the use requirements during the adjustment process); when the image plane of the display screen coincides with the image plane of the image transfer lens group 2, the adjustment is completed. At this time, the display adjustment rings 7 are fixed to the front end of the image transfer lens tube by dispensing glue and fixing screws, thereby fixing the position of the display screen.

[0073] Furthermore, the eyepiece assembly 1 is connected to the eyepiece barrel 6 via a multi-start thread.

[0074] Furthermore, a diopter adjustment ring 11 is provided at the rear end of the eyepiece assembly 1 for rotating the eyepiece assembly 1 to adjust the diopter.

[0075] Furthermore, a stop ring 10 is connected to the rear end of the eyepiece barrel 6 to limit the movement of the eyepiece group 1 and prevent the eyepiece group 1 from being rotated out of the eyepiece barrel 6.

[0076] Furthermore, a third sealing ring is provided between the eyepiece assembly 1 and the eyepiece barrel 6 .

[0077] Furthermore, the optical system of the compact continuous zoom eyepiece includes a field stop, a field lens, a first focusing lens group, a second focusing lens group, and an eyepiece group 1 optical system arranged in sequence from the display screen to the human eye;

[0078] The first focusing lens group is formed by gluing together a first focusing lens with positive focal power, a second focusing lens with negative focal power, and a third focusing lens with positive focal power, which are arranged in sequence from the display screen to the human eye;

[0079] The second focusing lens group includes a fourth focusing lens with positive focal length, a fifth focusing lens with positive focal length (in this embodiment, the fifth focusing lens is an aspherical lens to reduce the spherical aberration of the optical system), and a sixth focusing lens with positive focal length, which are sequentially arranged from the display screen to the human eye.

[0080] The optical system of the eyepiece group 1 includes a first eyepiece lens with negative optical power, a second eyepiece lens with positive optical power, a third eyepiece lens with positive optical power, and a fourth eyepiece lens with positive optical power, which are arranged in sequence from the display screen to the human eye.

[0081] Furthermore, each lens in the optical system of the compact continuous zoom eyepiece is made of glass material.

[0082] Furthermore, the focal length fa of the field lens satisfies: 1047.93 mm ≤ fa ≤ 1069.11 mm;

[0083] The focal length fb of the first focusing lens group satisfies: 57.45 mm ≤ fb ≤ 63.49 mm;

[0084] The focal length fc of the second focusing lens group satisfies: 18.28 mm ≤ fc ≤ 20.20 mm;

[0085] The focal length fd of the optical system of the eyepiece group 1 satisfies: 21.52 mm ≤ fd ≤ 23.78 mm.

[0086] Furthermore, the air gap between the field stop and the field lens is 9.01 mm;

[0087] The variable air gap between the field lens and the first focusing lens group ranges from 1.82mm to 14.5mm;

[0088] The variable air gap between the first and second focusing lens groups is 0.25 mm to 4.4 mm. The spacing between the first and second focusing lens groups is greater than 4 mm, ensuring that there is no interference between the two during movement.

[0089] The variable air gap between the second focusing lens group and the eyepiece group 1 optical system is 27.92mm~15.65mm;

[0090] The steering lens group forms an image on the diopter adjustment image plane, which is conjugate to the field stop. The air gap between the diopter adjustment image plane and the optical system of the eyepiece group 1 is 12.8 mm.

[0091] Furthermore, the first lens of the eyepiece and the second lens of the eyepiece are glued together to form an eyepiece glued lens, and the focal length fe of the eyepiece glued lens satisfies: 93.2mm≤fe≤95.08mm.

[0092] Furthermore, the air gap between the eyepiece cemented lens and the third lens of the eyepiece is 0.2 mm.

[0093] Furthermore, the air gap between the third lens of the eyepiece and the fourth lens of the eyepiece is 0.2 mm.

[0094] The optical system parameters of the compact continuous zoom eyepiece in the embodiment are shown in the following table:

[0095] Table 1 Optical system parameters of the compact continuous zoom eyepiece

[0096]

[0097] wherein the aspheric coefficients are according to the even aspheric formula

[0098] wherein r is the aperture in the direction perpendicular to the optical axis, z is the sag of the aspheric surface at the position with the height of r along the optical axis, c is the vertex curvature radius of the surface, k is the conic coefficient, a is the high-order aspheric coefficient, see the following table, and i is the aspheric order.

[0099] Table 2 Aspheric coefficients

[0100]

[0101] The variable air gap data in Table 1 are shown in the following table:

[0102] Table 3 Zoom system interval

[0103]

[0104] The zoom range of the compact continuous zoom eyepiece in the embodiment is 6.6x~18.9x, the exit pupil diameter is 7mm, the exit pupil distance is 45mm, and the eyecup is adapted.

[0105] The central MTF of the zoom eyepiece is >0.7@30lp / mm and the edge MTF is >0.5@lp / mm at the high magnification of 19.8x, and the central MTF is >0.5@30lp / mm and the edge MTF is >0.45@30lp / mm at the low magnification of 6.6x. The optical characteristics of the eyepiece at the high magnification and the low magnification are shown in Figures 3 to 11 .

[0106] Further, the field lens is fixed to the third focusing lens frame by a compression ring, for reducing the total length of the system and making the structure compact, the third focusing lens frame is precisely positioned and matched with the turning lens tube, and the third focusing lens frame and the turning lens tube can be fixed by a screw and a nut.

[0107] The compact continuous zoom eyepiece in the embodiment has a simple and compact structure (total length 76mm) and is easy to process and assemble, and the dynamic zoom adjustment mode of the traditional white light sighting scope is integrated on the basis of the digitalized gun sighting scope, so that the eyepiece is easy to use. The eyepiece can stably and reliably work under the environments of high and low temperature, raining, impact and vibration.

[0108] 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, or 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.

[0109] 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 shall be included in the scope of protection of the present invention.

Claims

1. A compact zoom eyepiece, characterized in that: include: Eyepiece tube, eyepiece connector, display screen assembly, zoom handwheel, adapter circuit board assembly, image transfer lens assembly, eyepiece assembly; The eyepiece connector is connected to the external sight body and the eyepiece tube respectively; The display screen assembly includes a display screen, a display screen circuit board, and a display screen frame; The adapter circuit board assembly is fixed in the eyepiece joint, and the display screen assembly is fixed in the front end of the image transfer lens assembly; The front and rear ends of the image-transmitting lens group are respectively fixed to the eyepiece joint and the eyepiece barrel. The image-transmitting lens group includes an image-transmitting lens tube, a magnification tube, a first focusing lens group, a second focusing lens group, and a third focusing lens group. The magnification hand wheel is sleeved on the outside of the eyepiece barrel and is in transmission connection with the first focusing lens group and the second focusing lens group. The eyepiece assembly is connected to the rear end of the eyepiece tube.

2. The compact zoom eyepiece according to claim 1, characterized in that: The first focusing lens group includes a first focusing lens and a first focusing lens frame, the second focusing lens group includes a second focusing lens and a second focusing lens frame, and the third focusing lens group includes a field lens and a third focusing lens frame; The field lens is fixed to the third focusing lens frame, and the third focusing lens frame is fixed to the front end of the image relay lens tube; A straight groove is provided on the side of the image-relay lens tube; The zoom tube is sleeved outside the image-shifting lens tube, and the zoom tube is axially limited by the front end of the steering lens tube and the zoom tube pressure ring; a first curved groove and a second curved groove are provided on the side of the zoom tube; The first focusing lens and the second focusing lens are fixed in the first focusing lens frame and the second focusing lens frame respectively. The first focusing lens frame and the second focusing lens frame are axially slidable in the image transfer lens tube. The first focusing lens frame and the second focusing lens frame are connected to the outside of each of the first focusing lens frame and the second focusing lens frame. The outer ends of the sliding screws pass through the straight groove of the image transfer lens tube and are respectively located in the first curved groove and the second curved groove of the magnification tube. A zoom slot with a certain opening angle is provided on the side of the eyepiece barrel. The outer end of the zoom rotating screw is fixed to the zoom handwheel, and the inner end of the zoom rotating screw passes through the zoom slot of the eyepiece barrel and is connected to the zoom tube.

3. The compact zoom eyepiece according to claim 2, characterized in that: A gasket is provided between the end of the image relay lens tube and the end of the magnification changer tube.

4. The compact zoom eyepiece according to claim 2, characterized in that: The maximum rise angle of the first curved groove and the second curved groove is 35.5°.

5. The compact zoom eyepiece according to claim 1, characterized in that: The eyepiece assembly is connected to the eyepiece barrel through a multi-start thread.

6. The compact zoom eyepiece according to claim 1 or 5, characterized in that: The rear end of the eyepiece tube is connected with a stop ring.

7. The compact zoom eyepiece according to claim 1, characterized in that: The optical system of the compact continuous zoom eyepiece includes a field stop, a field lens, a first focusing lens group, a second focusing lens group, and an eyepiece optical system arranged in sequence from the display screen to the human eye; The first focusing lens group is formed by gluing together a first focusing lens with positive focal power, a second focusing lens with negative focal power, and a third focusing lens with positive focal power, which are arranged in sequence from the display screen to the human eye; The second focusing lens group includes a fourth focusing lens with positive focal length, a fifth focusing lens with positive focal length, and a sixth focusing lens with positive focal length, which are sequentially arranged from the display screen to the human eye; The eyepiece optical system includes a first eyepiece lens with negative optical power, a second eyepiece lens with positive optical power, a third eyepiece lens with positive optical power, and a fourth eyepiece lens with positive optical power, which are arranged in sequence from the display screen to the human eye.

8. The compact zoom eyepiece according to claim 1 or 7, characterized in that: All lenses in the optical system of the compact zoom eyepiece are made of glass.

9. The compact zoom eyepiece according to claim 7, characterized in that: The focal length fa of the field lens satisfies: 1047.93mm≤fa≤1069.11mm; The focal length fb of the first focusing lens group satisfies: 57.45 mm ≤ fb ≤ 63.49 mm; The focal length fc of the second focusing lens group satisfies: 18.28 mm ≤ fc ≤ 20.20 mm; The focal length fd of the eyepiece optical system satisfies: 21.52 mm ≤ fd ≤ 23.78 mm; The first eyepiece lens and the second eyepiece lens are cemented to form an eyepiece cemented lens, and the focal length fe of the eyepiece cemented lens satisfies: 93.2mm≤fe≤95.08mm.

10. The compact zoom eyepiece according to claim 7, characterized in that: The air gap between the field stop and the field lens is 9.01 mm; The variable air gap between the field lens and the first focusing lens group ranges from 1.82mm to 14.5mm; The variable air gap between the first focusing lens group and the second focusing lens group is 0.25mm~4.4mm; The variable air gap between the second focusing lens group and the eyepiece group optical system is 27.92mm~15.65mm; The steering lens group forms an image on the diopter adjustment image plane, which is conjugate to the field stop. The air gap between the diopter adjustment image plane and the eyepiece optical system is 12.8 mm.

Images