Long-focus large-zoom-ratio television system based on double focusing

Abstract

The invention relates to a long-focus large-zoom-ratio television system based on double focusing. The system comprises a lens tube 1, a zoom lens tube 2, a front focusing group 3, a zoom group 4, a compensation group 5, a rear focusing group 6, an optical filter switching group 7, a rear fixing group 8, a pin group 11, a high-definition imaging module 17 and the like, wherein light reflected by a target passes through the front focusing group 3, the zoom group 4, the compensation group 5, the rear fixing group 8 and the rear focusing group 6 and is imaged on the high-definition imaging module 17. The front focusing group 3, the zoom group 4, the compensation group 5, the rear focusing group 6 and the like are respectively driven to translate in the lens tube 1 through sliding of the pin groups 11 in different curve grooves so as to realize continuous change of focal length, and the front focusing group 3 is used for compensating image surface movement caused by object distance change in a small field of view. And the rear focusing group 6 is used for compensating image surface movement caused by environment temperature change in a large field of view. The focal length of the television system is 25mm-1500mm, the zoom ratio is as high as 60 times, and the television system can still work stably in an environment of-45 DEG C to + 90 DEG C.

Description

Technical Field

[0001] The invention relates to the technical field of optical lenses, and in particular to a long-focus and large-zoom-ratio television system based on double focusing. Background Art

[0002] Existing television imaging equipment is generally composed of optical lenses, detector components and control circuit components, among which the lens is the foundation, through which the optical image of the target can be obtained. In actual use, television imaging equipment requires as large a field of view as possible to observe the target situation and search for the target. On the other hand, once the target is found, it needs a long focal length with a small field of view and a large magnification to magnify the target in order to accurately identify and track the target. This requires the lens to have as large a short focal length observation field of view as possible and a sufficient zoom ratio (i.e. the ratio of long focal length to short focal length). However, an increase in the field of view and zoom ratio will lead to a decrease in the imaging quality of the imaging module, a decrease in resolution, and difficulty in fitting the zoom curve, which ultimately increases the difficulty of the optical design of the lens. In addition, the optical aperture of the lens will also increase, resulting in an increase in the volume and weight of the product, and an increase in the difficulty of structural design.

[0003] In order to achieve clear imaging of targets of different distances and sizes within a certain range, a continuous zoom lens is usually used. The continuous zoom lens mainly realizes the continuous change of focal length by moving the zoom group, compensation group, etc. along the optical axis according to a certain rule, so that the image plane of the device can still remain clear and stable. The compensation group mainly compensates for the movement of the image plane when the zoom group moves. The television imaging device equipped with a continuous zoom lens is called a continuous zoom television system. Its focal length changes continuously within a certain range, while the image plane remains unchanged or basically unchanged. The zoom group and compensation lens group of the continuous zoom television system are mainly driven by the cam curve groove to move relative to each other in the axial direction according to a certain rule, thereby realizing the continuous change of focal length. The compensation group is mainly used to compensate for the movement of the image plane, while the focusing group is mainly used to compensate for the movement of the image plane caused by changes in target distance, changes in ambient temperature, etc.

[0004] Due to the limitations of optical processing technology, zoom lens tube cam curve groove design and processing technology, as well as the requirement that the image must remain clear during continuous zooming, the zoom ratio of existing continuous zoom television systems is generally around 10x to 15x, and the telephoto focus is generally below 500mm, which cannot meet the increasingly high application requirements. Summary of the invention

[0005] The main purpose of the present invention is to overcome the problems of small zoom ratio and telephoto, poor imaging quality and insufficient portability of existing television imaging devices, and develop a new type of television system with long focal length and large zoom ratio based on dual focus, which includes a lens tube 1, a zoom lens tube 2, a front focusing group 3, a zoom group 4, a compensation group 5, a rear focusing group 6, and a rear fixing group 8. The front focusing group 3, the zoom lens tube 4, the compensation group 5, the rear focusing group 6, and the rear fixing group 8 are all coaxially installed in the lens tube 1, and the zoom lens tube 2 is sleeved on the lens tube 1. The front focusing group 3 and the rear focusing group 6 can independently reciprocate in a straight line in the lens tube 1, so as to compensate for the image plane movement caused by the change of telephoto object distance and the image plane movement caused by the change of ambient temperature, respectively, to ensure that the large field of view image distortion and resolution meet the index requirements, and to ensure that the image is clear throughout the zoom process. The zoom lens tube 2 drives the zoom group 4 and the compensation group 5 to move back and forth in a straight line in the lens tube 1 through the zoom curve groove and the compensation curve groove, so as to realize the continuous change of the focal length and compensate the movement of the image plane at the same time.

[0006] Furthermore, the system further comprises a front focusing motor group 9 and a front focusing gear 12 matched with the front focusing group 3, wherein the front focusing gear 12 is movably mounted on the mirror tube 1, and the front focusing motor group 9 is fixed on the mirror tube 1 and meshes with the front focusing gear 12 for transmission. A focusing cam curve groove is provided on the front focusing gear 12, and a matching straight groove is provided on the mirror tube 1. One end of the pin group 11 is fixedly connected to the front focusing group 3, and the other end of the pin group 11 passes through the straight groove on the mirror tube 1 and is located in the focusing cam curve groove of the front focusing gear 12.

[0007] Furthermore, the front focusing group 3 includes a concave-convex lens a1, a biconvex lens a2, a concave-convex lens a3, a concave-convex lens a4, and a concave-convex lens a5 which are coaxially arranged in sequence, and the concave-convex lens a1 and the biconvex lens a2, the concave-convex lens a3 and the concave-convex lens a4 are bonded together.

[0008] Furthermore, the system also includes a variable power motor group 10, which is fixed on the lens tube 1 and connected to the variable power lens tube 2 for transmission. The variable power lens tube 2 is provided with a variable power cam curve groove and a compensation cam curve groove, and a matching straight line groove is provided on the lens tube 1. One end of a group of pin groups 11 is fixedly connected to the variable power group 4, and the other end of the pin group 11 passes through the straight line groove on the lens tube 1 and is located in the variable power cam curve groove of the variable power lens tube 2; one end of another group of pin groups 11 is fixedly connected to the compensation group 5, and the other end of the pin group 11 passes through the straight line groove on the lens tube 1 and is located in the compensation cam curve groove of the variable power lens tube 2.

[0009] Furthermore, the zoom group 4 includes a biconcave lens b1, a biconvex lens b2, and a biconcave lens b3 which are coaxially arranged in sequence, wherein the biconvex lens b2 and the biconcave lens b3 are bonded together.

[0010] Furthermore, the compensation group 5 includes a biconcave lens c1, a meniscus lens c2, a biconcave lens c3, and a meniscus lens c4 which are coaxially arranged in sequence, wherein the biconcave lens c1 and the meniscus lens c2, and the biconcave lens c3 and the meniscus lens c4 are bonded together.

[0011] Furthermore, the system also includes a rear focusing gear 14 and a rear focusing motor group 15 matched with the rear focusing group 6, wherein the rear focusing gear 14 is movably mounted on the mirror tube 1, and the rear focusing motor group 15 is fixed on the mirror tube 1 and meshes with the rear focusing gear 14 for transmission. A focusing cam curve groove is provided on the rear focusing gear 14, and a matching straight groove is provided on the mirror tube 1. One end of the pin group 11 is fixedly connected to the rear focusing group 6, and the other end of the pin group 11 passes through the straight groove on the mirror tube 1 and is located in the focusing cam curve groove of the rear focusing gear 14.

[0012] Furthermore, the rear fixed group 8 includes a biconvex lens e1, a concave-convex lens e2, a concave-convex lens e3, a concave-convex lens e4, a concave-convex lens e5, a biconcave lens e6, a concave-convex lens e7, a concave-convex lens e8, a concave-convex lens e9, a concave-convex lens e10, and a concave-convex lens e11, which are coaxially arranged in sequence, wherein the biconvex lens e1 is bonded to the concave-convex lens e2, and the concave-convex lens e4 is bonded to the concave-convex lens e5.

[0013] Furthermore, the rear focusing group 6 includes a double concave lens d1 , which is dispersedly arranged between the meniscus lens e8 and the meniscus lens e9 of the rear fixed group 8 .

[0014] Furthermore, the system also includes a filter switching group 7 and a high-definition imaging module 17, wherein the filter switching group 7 and the high-definition imaging module 17 are both fixedly connected to the rear fixing group 8, and the filter switching group 7 is located between the high-definition imaging module 17 and the rear fixing group 8.

[0015] Furthermore, the filter switching group 7 includes a visible light filter and a near infrared filter.

[0016] Furthermore, the system also includes a filter switching motor group 13 matched with the filter switching group 7. The filter switching motor group 13 is fixed on the mirror tube 1 and is connected to the filter switching group 7 for transmission. The switching of each filter is achieved by rotating the filter switching group 7.

[0017] Compared with existing similar products, the advantages of the dual-focus long-focus and large-zoom-ratio television system provided by the present invention are mainly reflected in the following aspects: (1) The focal length of the television system is 25mm-1500mm (usually below 500mm), the zoom ratio is as high as 60 times (usually 10-15 times), and it can be applied to the working environment of -45℃~+90℃. Even in harsh environments, it can still stably observe and search for targets in a large range; (2) The television system uses the front focusing group to compensate for the image plane movement caused by the change of object distance under a small field of view, and uses the rear focusing group to compensate for the image plane movement caused by the change of ambient temperature under a large field of view. It has many advantages such as clear imaging, high resolution, small size and light weight; (3) The television system is equipped with an adjustable aperture and filter switching mechanism, etc., which can cope with various harsh environments or climates. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a stereoscopic diagram of a long focal length and large zoom ratio television system based on dual focusing.

[0019] Figure 2 This is the main view of the long-focus and large-zoom-ratio television system based on dual focusing.

[0020] Figure 3 for Figure 2 Half section view.

[0021] Figure 4 It is a top view of a long focal length and large zoom ratio television system based on dual focusing.

[0022] Figure 5 This is a three-dimensional schematic diagram of the rear focusing gear.

[0023] Figure 6 It is a three-dimensional schematic diagram of the mirror tube.

[0024] Figure 7 It is a three-dimensional schematic diagram of the zoom lens tube.

[0025] Figure 8 It is a three-dimensional schematic diagram of the filter switching group.

[0026] Fig. 9 Schematic diagram of the optical path.

[0027] Figure markings: 1-lens tube, 2-zoom lens tube, 3-front focusing group, 4-zoom group, 5-compensation group, 6-rear focusing group, 7-filter switching group, 8-rear fixing group, 9-front focusing motor group, 10-zoom motor group, 11-pin group, 12-front focusing gear, 13-filter switching motor group, 14-rear focusing gear, 15-rear focusing motor group, 16-control circuit board, 17-high-definition imaging module. DETAILED DESCRIPTION

[0028] In order to enable ordinary technicians in the field to fully understand the technical solutions and beneficial effects of the present invention, the following is further described in detail in conjunction with specific embodiments and drawings. It should be emphasized that the embodiments listed below are only preferred implementations of the present invention, and many improvements can be made without violating the main purpose of the present invention, and these technical solutions will fall within the scope of protection of the present invention.

[0029] like Figure 1-8 The telephoto large zoom ratio television system based on dual focusing is shown, which mainly includes a lens tube 1, a zoom lens tube 2, a front focusing group 3, a zoom group 4, a compensation group 5, a rear focusing group 6, a filter switching group 7, a rear fixing group 8, a front focusing motor group 9, a zoom motor group 10, a pin group 11, a front focusing gear 12, a filter switching motor group 13, a rear focusing gear 14, a rear focusing motor group 15, a control circuit board 16, and a high-definition imaging module 17. The lens tube 1 is the assembly body, and the other components are directly or indirectly fixed inside, on the surface, or at both ends of the lens tube 1. The specific assembly relationship is as follows:

[0030] like Figure 6 As shown, a plurality of groups of linear grooves are arranged along the axial direction on the surface of the mirror tube 1. Figure 3 As shown, the front focusing group 3 is installed inside the left end of the mirror tube 1, and the front focusing gear 12 is coaxially sleeved on the outside of the left end of the mirror tube 1. Screw holes are symmetrically arranged on the surface of the front focusing group 3, and a focusing cam curve groove c and a transmission tooth are arranged on the surface of the front focusing gear 12 along the circumferential direction. One end of the pin group 11 is respectively fixed in the screw holes on the surface of the front focusing group 3, and the other end of the pin group 11 passes through the linear groove on the left end surface of the mirror tube 1 and is located in the focusing cam curve groove c of the front focusing gear 12. The front focusing motor group 9 is fixed on the mirror tube 1 and meshes with the transmission teeth of the front focusing gear 12 for transmission. In this way, when the front focusing motor group 9 is powered on and rotated, the front focusing gear 12 is driven to rotate through the transmission teeth, and the pin group 11 slides in the focusing cam curve groove c of the front focusing gear 12, thereby driving the front focusing group 3 to move left and right in parallel in the mirror tube 1, thereby achieving fine focusing and providing a stable target image.

[0031] The zoom lens tube 2 is coaxially mounted on the outside of the lens tube 1, and the zoom group 4 and the compensation group 5 are both installed inside the lens tube 1 and are coaxial with the front focusing group 3, the rear focusing group 6, the filter switching group 7, and the rear fixing group 8. The left and right movement principle of the zoom group 4 and the compensation group 5 is similar to that of the front focusing group 3, which is as follows: the zoom cam curve groove a, the compensation cam curve groove b and the transmission teeth are respectively arranged on the surface of the zoom lens tube 2 along the circumferential direction, and the zoom cam curve groove a and the compensation cam curve groove b each include two groups of symmetrical and evenly distributed curve grooves (such as Figure 7As shown). One end of the pin group 11 is fixed in the screw hole on the surface of the zoom group 4, and the other end passes through the linear groove on the lens tube 1 and is located in the zoom cam curve groove a of the zoom lens tube 2. Similarly, one end of another pair of pin groups 11 is fixed in the screw hole on the surface of the compensation group 5, and the other end passes through the linear groove on the lens tube 1 and is located in the compensation cam curve groove b of the zoom lens tube 2. A zoom motor group 10 is fixed on the outer surface of the lens tube 1, and the zoom motor group 10 is meshed with the zoom lens tube 2 through transmission teeth. When the zoom motor group 10 is powered on and rotated, the zoom lens tube 2 is driven to rotate under the action of the transmission teeth, and different pin groups 11 slide in the zoom cam curve groove a and the compensation cam curve groove b respectively, driving the zoom group 4 and the compensation group 5 to move left and right in parallel in the lens tube 1, thereby realizing continuous change of focal length.

[0032] The rear fixing group 8 is fixedly mounted on the right end of the lens tube 1 and is used to fine-tune the synthetic focal length of the continuous zoom lens system, thereby ensuring that the system image falls on the image plane.

[0033] like Figure 3 As shown, the rear focusing group 6 is installed inside the right end of the lens tube 1, and the rear focusing gear 14 is coaxially sleeved on the outside of the right end of the lens tube 1. Figure 5 As shown, a rear focusing cam curve groove d and a transmission tooth are arranged on the surface of the rear focusing gear 14 along the circumferential direction. One end of the pin group 11 is fixed in the screw hole on the surface of the rear focusing group 6, and the other end of the pin group 11 passes through the linear groove on the right end surface of the mirror tube 1 and is located in the rear focusing cam curve groove d on the surface of the rear focusing gear 14. A rear focusing motor group 15 is fixed on the surface of the mirror tube 1, and the rear focusing motor group 15 is meshed with the rear focusing gear 14 through the transmission teeth. When the rear focusing motor group 15 is powered on and rotated, it drives the rear focusing gear 14 to rotate, and the pin group 11 slides in the rear focusing cam curve groove d, driving the rear focusing group 6 to move parallel to the left and right in the mirror tube 1, thereby realizing rear fine focusing and compensating for the image plane offset under the condition of large field of view.

[0034] The filter switching group 7 is located between the high-definition imaging module 17 and the rear fixed group lens group, and is fixed on the rear fixed group 8. Figure 8 As shown, the filter switching group 7 includes a filter switching motor group 13 and a switching gear group. The visible light filter and the near-infrared filter are connected to the switching gear group. The filter switching motor group 13 drives the switching gear group to rotate through gear transmission, thereby realizing the visible light filter and the near-infrared filter to alternately cut in and out of the main light path, thereby completing the rapid switching of the filter.

[0035] The high-definition imaging module 17 is also fixedly connected to the rear fixing group 8, and is mainly used to receive the target optical image and form a high-definition video or image output through photoelectric conversion, image enhancement processing, etc. The control circuit board 16 is connected to the high-definition imaging module 17 and each motor group for power supply and control of their operation.

[0036] The optical path diagram of the telephoto large zoom ratio television system is as follows Fig. 9 As shown, it mainly includes a front focusing group 3, a zoom group 4, a compensation group 5, a rear focusing group 6, and a rear fixed group 8. The front focusing group 3 includes a concave-convex lens a1, a biconvex lens a2, a concave-convex lens a3, a concave-convex lens a4, and a concave-convex lens a5 arranged coaxially in sequence, wherein the concave-convex lens a1 is bonded to the biconvex lens a2, and the concave-convex lens a3 is bonded to the concave-convex lens a4. The zoom group 4 includes a biconcave lens b1, a biconvex lens b2, and a biconcave lens b3 arranged coaxially in sequence, wherein the biconvex lens b2 is bonded to the biconcave lens b3. The compensation group 5 includes a biconcave lens c1, a concave-convex lens c2, a biconcave lens c3, and a concave-convex lens c4 arranged coaxially in sequence, wherein the biconcave lens c1 is bonded to the concave-convex lens c2, and the biconcave lens c3 is bonded to the concave-convex lens c4. The rear fixed group 8 includes a biconvex lens e1, a concave-convex lens e2, a concave-convex lens e3, a concave-convex lens e4, a concave-convex lens e5, a biconcave lens e6, a concave-convex lens e7, a concave-convex lens e8, a concave-convex lens e9, a concave-convex lens e10, and a concave-convex lens e11, which are coaxially arranged in sequence, wherein the biconvex lens e1 is bonded to the concave-convex lens e2, and the concave-convex lens e4 is bonded to the concave-convex lens e5. The rear focusing group 6 includes a biconcave lens d1, which is arranged between the concave-convex lens e8 and the concave-convex lens e9 of the rear fixed group 8. The optical parameters of each lens of the telephoto large zoom ratio television system are as follows:

[0037] Serial number Part Number Radius (unit: mm) Thickness (mm) Material 1 a1 -25，-119 6.2 H-LAK51A 2 a2 -119，529.7 17.5 H-FK61B 3 a3 -323.6，-89 6.2 H-FK61B 4 a4 -89，-1282.3 16.7 H-FK61B 5 a5 -86.7，-580.8 15.6 H-FK61B 6 b1 409.3，-105 4 H-ZF73GT 7 b2 -110，59.7 12.8 H-ZF73GT 8 b3 59.7，-39.4 2.9 H-ZLAF68C 9 c1 313，-16.8 1.2 H-FK95N 10 c2 -16.8，-47.3 1.7 H-FK95N 11 c3 29.7，-28.2 1.3 H-FK95N 12 c4 -28.2，140.6 2.5 H-ZLAF56B 13 d1 24.1，-17.4 1 H-ZPK1A 14 e1 -26.6，40.7 6 H-FK95N 15 e2 40.7，73.96 1.4 H-FK95N 16 e3 -32.8，-194.5 7.2 H-LAK50A 17 e4 -230.7，-12.5 1.5 H-LAK50A 18 e5 -12.5，927.7 4.7 H-FK95N 19 e6 33.8，1652 1.4 H-FK95N 20 e7 -28.84，-16.872 1.1 H-FK95N 21 e8 -12.9，-23.4 1.8 H-FK95N 22 e9 21.8，-39.8 1 H-ZPK1A 23 e10 -12.97，-122.1 3.4 H-FK95N 24 e11 -17.5，-28.2 2.7 H-ZLAF89L

[0038] The telephoto large zoom ratio television system based on dual focusing provided by the present invention has optical components such as a front focusing group 3, a zoom group 4, a compensation group 5, a rear focusing group 6, and a rear fixed group 8. The light reflected by the target passes through the optical components such as the front focusing group 3, the zoom group 4, the compensation group 5, the rear focusing group 6, and the rear fixed group 8, and is imaged on the image plane of the high-definition imaging module 17. The television system has two groups of front and rear focusing mechanisms, wherein the front focusing group compensates for the image plane movement caused by the change of the telephoto object distance, and the rear focusing group compensates for the image plane movement caused by the change of the ambient temperature. Through the front and rear focusing compensation, it can be ensured that the large field of view image distortion and resolution meet the index requirements, and the image is clear throughout the zoom process. The filter switching group 7 located after the rear fixed group 8 drives different filters to switch through the motor, which can realize the rapid conversion of visible light imaging and fog-penetrating imaging.

[0039] The telephoto large zoom ratio television system based on dual focus provided by the present invention has a focal length of 25mm-1500mm and a zoom ratio of up to 60 times, and has the remarkable characteristics of telephoto large zoom ratio. The television system has the advantages of small size, light weight, high sensitivity, etc. under the premise of ensuring high imaging quality, and can be installed on various optoelectronic devices for searching, magnifying observation and accurate tracking of targets, and can still work stably even in an environment of -45℃~+90℃.

Claims

1. A dual-focus telephoto large zoom ratio television system, characterized in that: The system comprises a lens tube (1), a zoom lens tube (2), a front focusing group (3), a zoom group (4), a compensation group (5), a rear focusing group (6), and a rear fixing group (8), wherein the front focusing group (3), the zoom group (4), the compensation group (5), the rear focusing group (6), and the rear fixing group (8) are coaxially mounted in the lens tube (1), and the zoom lens tube (2) is sleeved on the lens tube (1); the front focusing group (3) and the rear focusing group (6) can both perform linear reciprocating motion in the lens tube (1), and the zoom lens tube (2) drives the zoom group (4) and the compensation group (5) to perform linear reciprocating motion in the lens tube (1) through different curved grooves.

2. The television system according to claim 1, characterized in that: The system further comprises a front focusing motor group (9) and a front focusing gear (12) matched with the front focusing group (3); the front focusing gear (12) is movably sleeved on the mirror tube (1); the front focusing motor group (9) is fixed on the mirror tube (1) and meshes with the front focusing gear (12) for transmission; a focusing cam curve groove is provided on the front focusing gear (12); a matching straight groove is provided on the mirror tube (1); one end of the pin group (11) is fixedly connected to the front focusing group (3); the other end of the pin group (11) passes through the straight groove on the mirror tube (1) and is located in the focusing cam curve groove of the front focusing gear (12).

3. The television system according to claim 1, wherein: The system further comprises a variable power motor group (10), the variable power motor group (10) being fixed on the lens tube (1) and connected to the variable power lens tube (2) for transmission, the variable power lens tube (2) being provided with a variable power cam curve groove and a compensation cam curve groove, and the lens tube (1) being provided with a matching straight line groove; one end of a group of pin groups (11) being fixedly connected to the variable power group (4), the other end of the pin group (11) passing through the straight line groove on the lens tube (1) and being located in the variable power cam curve groove of the variable power lens tube (2); one end of another group of pin groups (11) being fixedly connected to the compensation group (5), the other end of the pin group (11) passing through the straight line groove on the lens tube (1) and being located in the compensation cam curve groove of the variable power lens tube (2).

4. The television system according to claim 1, wherein: The system further comprises a rear focusing gear (14) and a rear focusing motor group (15) matched with the rear focusing group (6); the rear focusing gear (14) is movably sleeved on the mirror tube (1); the rear focusing motor group (15) is fixed on the mirror tube (1) and meshes with the rear focusing gear (14) for transmission; a focusing cam curve groove is provided on the rear focusing gear (14); a matching straight groove is provided on the mirror tube (1); one end of the pin group (11) is fixedly connected to the rear focusing group (6); the other end of the pin group (11) passes through the straight groove on the mirror tube (1) and is located in the focusing cam curve groove of the rear focusing gear (14).

5. The television system according to claim 1, wherein: The system further comprises a filter switching group (7) and a high-definition imaging module (17), wherein the filter switching group (7) and the high-definition imaging module (17) are both fixedly connected to the rear fixing group (8), and the filter switching group (7) is located between the high-definition imaging module (17) and the rear fixing group (8), and the filter switching group (7) comprises a visible light filter and a near-infrared filter.

6. The television system according to claim 5, characterized in that: The system also comprises a filter switching motor group (13) matched with the filter switching group (7); the filter switching motor group (13) is fixed on the mirror tube (1) and is connected to the filter switching group (7) for transmission.

7. The television system according to claim 1, characterized in that: The front focusing group (3) comprises a concave-convex lens a1, a biconvex lens a2, a concave-convex lens a3, a concave-convex lens a4 and a concave-convex lens a5 which are coaxially arranged in sequence, wherein the concave-convex lens a1 is bonded to the biconvex lens a2, and the concave-convex lens a3 is bonded to the concave-convex lens a4; the zoom group 4 comprises a biconcave lens b1, a biconvex lens b2 and a biconcave lens b3 which are coaxially arranged in sequence, wherein the biconvex lens b2 is bonded to the biconcave lens b3; the compensation group 5 comprises a biconcave lens c1, a concave-convex lens c2, a biconcave lens c3 and a concave-convex lens c4 which are coaxially arranged in sequence, wherein the biconcave lens c1 is bonded to the concave-convex lens c2, and the biconcave lens c3 is bonded to the concave-convex lens c4.

8. The television system according to claim 1, wherein: The rear fixed group (8) comprises a biconvex lens e1, a concave-convex lens e2, a concave-convex lens e3, a concave-convex lens e4, a concave-convex lens e5, a biconcave lens e6, a concave-convex lens e7, a concave-convex lens e8, a concave-convex lens e9, a concave-convex lens e10 and a concave-convex lens e11 which are coaxially arranged in sequence, wherein the biconvex lens e1 is bonded to the concave-convex lens e2, and the concave-convex lens e4 is bonded to the concave-convex lens e5.

9. The television system according to claim 8, characterized in that: The rear focusing group (6) comprises a biconcave lens d1, which is arranged between the meniscus lens e8 and the meniscus lens e9 of the rear fixed group (8).

10. The television system according to any one of claims 1 to 9, characterized in that: The focal length of the system is 25mm-1500mm, the zoom ratio is ≤60 times, and the operating temperature is -45℃~+90℃.

Images