Large-target-surface miniaturized continuous zoom lens

Abstract

The invention provides a large-target-surface miniaturized continuous zoom lens. The large-target-surface miniaturized continuous zoom lens comprises a front fixed group, a zoom group, a compensation group, a diaphragm, a rear fixed group and a filter lens group which are sequentially arranged in the light incidence direction, the front fixing group is used for receiving incident light and bearing the maximum focal power, the diaphragm is used for controlling the light incoming amount of the system and influencing the depth of field, the rear fixing group is used for correcting and optimizing a light path, and the filter lens group is used for realizing multi-mode filtering switching; wherein the zooming group and the compensation group are movably arranged along the optical axis direction, the zooming group is used for realizing a continuous zooming function, and the compensation group is movably matched with the zooming group along the optical axis direction to realize image surface stability in a zooming process. According to the invention, the zoom group and the compensation group are movably arranged along the optical axis direction, so that the continuous zooming function can be accurately realized by virtue of the movement of the zoom group, and the zoom group can be efficiently matched through the synchronous movement of the compensation group, so that the image surface is always stable in the zooming process, and finally, the use requirement of high-definition imaging is comprehensively met.

Description

Technical Field

[0001] This invention relates to the field of optical instrument technology, and in particular to a miniaturized continuous zoom lens with a large target surface. Background Technology

[0002] In the field of aerial detection, with the rapid development of technologies such as reconnaissance and surveillance, target tracking and security patrol, the lenses carried by airborne optoelectronic equipment need to meet the core requirements of smaller size and lighter weight. At the same time, since the equipment needs to achieve both large-scale target detection and small-scale target identification when performing high-altitude missions, the airborne lenses also need to have the functional characteristics of continuously variable focal length and high-definition imaging.

[0003] However, there are obvious shortcomings in the airborne optical systems equipped with large-scale cameras in China: on the one hand, the overall length of the system is relatively long, and it is often necessary to add mirrors to reduce the size, which is not conducive to miniaturization design; on the other hand, the environment of aerospace missions is more extreme, and the environmental adaptability of existing lenses still needs to be further improved; in addition, there are few lenses on the market that are compatible with large-scale cameras, which is difficult to meet the current development needs of airborne equipment for large-scale and miniaturized cameras.

[0004] Based on the above needs and pain points, there is an urgent need to further improve the performance of airborne optical systems so that airborne lenses can meet the comprehensive performance requirements of high relative illumination, large target area, low distortion, miniaturization, and strong environmental adaptability, in order to adapt to the technological development trend in the field of aerial detection. Summary of the Invention

[0005] The purpose of this invention is to provide a miniaturized continuous zoom lens with a large target surface, which solves the technical problem that existing airborne large target surface optical systems cannot simultaneously achieve large target surface, miniaturization, and continuous zoom high-definition imaging.

[0006] To address the aforementioned technical problems, this invention provides a miniaturized continuous zoom lens with a large target surface, comprising a front fixed group, a zoom group, a compensation group, an aperture stop, a rear fixed group, and a filter group arranged sequentially along the light incident direction; the front fixed group is used to receive incident light and bear the maximum optical power, the aperture stop is used to control the amount of light entering the system and affects the depth of field, the rear fixed group is used to correct and optimize the optical path, and the filter group is used to realize multi-mode filter switching; The zoom group and the compensation group are both movable along the optical axis. The zoom group achieves continuous zoom function by moving along the optical axis, and the compensation group works with the zoom group to stabilize the image plane during zooming by moving along the optical axis.

[0007] Preferably, the optical elements in the front fixed group, zoom group, compensation group and rear fixed group are all spherical mirrors, and all adopt non-cemented lens structures.

[0008] Preferably, the optical power of the front fixed group is positive, the optical power of the variable magnification group is negative, the optical power of the compensation group is positive, and the optical power of the rear fixed group is negative.

[0009] Preferably, the air gap between the front fixed group and the zoom group is 2.249–28.784 mm, the air gap between the zoom group and the compensation group is 2.5–48.918 mm, the air gap between the compensation group and the aperture is 1.489–21.372 mm, the air gap between the aperture and the rear fixed group is 4.88 mm, and the air gap between the rear fixed group and the filter group is 13.149 mm.

[0010] Preferably, the front fixed group includes a first meniscus lens, a first biconvex lens, and a first biconcave lens arranged sequentially along the incident direction of light; the zoom group includes a second biconvex lens, a second biconcave lens, and a third biconcave lens arranged sequentially along the incident direction of light; the compensation group includes a third biconvex lens, a fourth biconvex lens, a second meniscus lens, a third meniscus lens, and a fifth biconvex lens arranged sequentially along the incident direction of light; and the rear fixed group includes a fourth meniscus lens, a fifth meniscus lens, a sixth biconvex lens, a fourth biconcave lens, and a sixth meniscus lens arranged sequentially along the incident direction of light.

[0011] Preferably, the air gap between the first meniscus lens and the first biconvex lens is 0.3 mm; the air gap between the first biconvex lens and the first biconcave lens is 11.826 mm; the air gap between the first biconcave lens and the second biconvex lens is 2.249–28.784 mm; the air gap between the second biconvex lens and the second biconcave lens is 0.655 mm; the air gap between the second biconcave lens and the third biconcave lens is 6.553 mm; the air gap between the third biconcave lens and the third biconvex lens is 2.5–48.918 mm; the air gap between the third biconvex lens and the fourth biconvex lens is 0.3 mm; and the air gap between the fourth biconvex lens and the second meniscus lens is 0.321 mm. The air gap between the lens and the third meniscus lens is 0.3 mm; the air gap between the third meniscus lens and the fifth biconvex lens is 0.359 mm; the air gap between the fifth biconvex lens and the aperture stop is 1.489–21.372 mm; the air gap between the aperture stop and the fourth meniscus lens is 4.88 mm; the air gap between the fourth meniscus lens and the fifth meniscus lens is 0.308 mm; the air gap between the fifth meniscus lens and the sixth biconvex lens is 8.697 mm; the air gap between the sixth biconvex lens and the fourth biconcave lens is 0.3 mm; the air gap between the fourth biconcave lens and the sixth meniscus lens is 40.928 mm; and the air gap between the sixth meniscus lens and the filter group is 13.149 mm.

[0012] Preferably, the refractive index and Abbe number of each lens in the miniaturized continuous zoom lens with a large target surface satisfy the following conditions: 1.3 < n1 < 1.5, 1.3 < n2 < 1.5, 1.9 < n3 < 2.05, 1.85 < n4 < 2.05, 1.65 < n5 < 1.8, 1.65 < n6 < 1.8, 1.75 < n7 < 1.9, 1.5 < n8 < 1.65, 1.85 < n9 < 2.05, 1.75 < n 10 <1.95, 1.5 < n 11 <1.65, 1.75 < n 12 <1.95, 1.5 < n 13 <1.65, 1.75 < n 14 <1.95, 1.75 < n 15 <1.9, 1.85 < n 16 <2.05, 1.45 < n 17 <1.6; 85<V1<95, 85<V2<95, 28<V3<35, 16<V4<20, 40<V 5<50, 40<V6<50, 33<V7<41, 61<V8<76, 16<V9<20, 38<V 10 <47, 61 <V 11 <76, 38 < V 12 <47, 61 <V 13 <76, 27 < V 14 <34, 33 < V 15 <41, 16 < V 16 <20, 57 < V 17 <71; Among them, n1, n2, n3, n4, n5, n6, n7, n8, n9, n 10 n 11 n 12 n 13 n 14 n 15 n 16 and n 17 The refractive indices of the following lenses, in sequence: first meniscus lens, first biconvex lens, first biconcave lens, second biconvex lens, second biconcave lens, third biconcave lens, third biconvex lens, fourth biconvex lens, second meniscus lens, third meniscus lens, fifth biconvex lens, fourth meniscus lens, fifth meniscus lens, sixth biconvex lens, fourth biconcave lens, sixth meniscus lens, and filter group; V1, V2, V3, V4, V5, V6, V7, V8, V9, V 10 V 11 V 12 V 13 V 14 V 15 V16 and V 17 The Abbe numbers of the following lenses are, in order: first meniscus lens, first biconvex lens, first biconcave lens, second biconvex lens, second biconcave lens, third biconcave lens, third biconvex lens, fourth biconvex lens, second meniscus lens, third meniscus lens, fifth biconvex lens, fourth meniscus lens, fifth meniscus lens, sixth biconvex lens, fourth biconcave lens, sixth meniscus lens, and filter group.

[0013] Preferably, the filter assembly is a wheel-type structure with switchable filtering capabilities. The wheel-type structure includes a visible light filter, a near-infrared filter, and a polarizing filter arranged sequentially in a clockwise direction.

[0014] Preferably, the focal length f1 of the front fixed group is in the range of 156mm < f1 < 192mm; the focal length f2 of the zoom group is in the range of -47mm < f2 < -39mm; the focal length f3 of the compensation group is in the range of 42mm < f3 < 52mm; and the focal length f4 of the rear fixed group is in the range of -371mm < f4 < -303mm.

[0015] Preferably, the large-target miniaturized continuous zoom lens can be equipped with a large-target camera with a resolution of 8984×6732 under the condition that the target diagonal image height is 38mm, and the large-target miniaturized continuous zoom lens can be matched with a camera with a pixel size of 3.2μm, large field of view optical distortion ≤2.3%, and small field of view optical distortion ≤1%.

[0016] The beneficial effects of this invention are as follows: Unlike the prior art, this invention provides a miniaturized continuous zoom lens with a large target area, comprising a front fixed group, a zoom group, a compensation group, an aperture stop, a rear fixed group, and a filter group arranged sequentially along the light incident direction; the front fixed group is used to receive incident light and bear the maximum optical power, the aperture stop is used to control the amount of light entering the system and affect the depth of field, the rear fixed group is used to correct and optimize the optical path, and the filter group is used to realize multi-mode filter switching; wherein, the zoom group and the compensation group are both movable along the optical axis, the zoom group realizes the continuous zoom function by moving along the optical axis, and the compensation group cooperates with the zoom group to stabilize the image plane during the zoom process by moving along the optical axis. The miniaturized continuous zoom lens with a large target area provided by this invention, through the movable arrangement of the zoom group and the compensation group along the optical axis, can not only achieve continuous zoom function precisely by relying on the movement of the zoom group, but also efficiently cooperate with the zoom group through the synchronous movement of the compensation group to ensure that the image plane remains stable throughout the zoom process. At the same time, the miniaturized continuous zoom lens with a large target area works in concert with the front fixed group, the aperture, the rear fixed group and the filter group. The front fixed group completes the initial optical path transmission of incident light, the rear fixed group performs precise correction and optimization of the optical path, the aperture controls the amount of light entering the system, and the filter group meets the requirements of multi-mode filter switching. Finally, a fully functional, stable imaging and smooth zoom optical system is formed, which is fully adapted to the use requirements of high-definition imaging. Attached Figure Description

[0017] Figure 1 Structural diagrams of the large-target-area miniaturized continuous zoom lens provided in the embodiments of the present invention at short focal length and long focal length, respectively; Figure 2 A dot plot of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the visible light band at short focal lengths. Figure 3 The transfer function diagram of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the visible light band at short focal length. Figure 4 A dot plot of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the near-infrared band at a short focal length. Figure 5 The transfer function diagram of the large target area miniaturized continuous zoom lens provided in Embodiment 1 in the near-infrared band at a short focal length. Figure 6 A dot plot of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the visible light band of the telephoto range; Figure 7 The transfer function diagram of the large-target miniaturized continuous zoom lens provided in Embodiment 1 in the visible light band of the telephoto range. Figure 8 A dot plot of the near-infrared band in the telephoto range for the miniaturized continuous zoom lens with a large target area provided in Embodiment 1. Figure 9 The transfer function diagram of the large-target miniaturized continuous zoom lens provided in Embodiment 1 in the near-infrared band of the telephoto range. In the accompanying drawings: 10—Front fixed group; 101—First meniscus lens; 102—First biconvex lens; 103—First biconcave lens; 20—Magnification group; 201—Second biconvex lens; 202—Second biconcave lens; 203—Third biconcave lens; 30—Compensation group; 301—Third biconvex lens; 302—Fourth biconvex lens; 303—Second meniscus lens; 304—Third meniscus lens; 305—Fifth biconvex lens; 40—Aperture stop; 50—Rear fixed group; 501—Fourth meniscus lens; 502—Fifth meniscus lens; 503—Sixth biconvex lens; 504—Fourth biconcave lens; 505—Sixth meniscus lens; 60—Filter group; Detailed Implementation The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0018] The purpose of this invention is to address the shortcomings of existing technologies by providing a miniaturized continuous zoom lens with a large aperture, thereby achieving the requirements of high resolution and miniaturization. This lens optimizes its optical structure, avoids using cemented glass, and employs a separate four-element structure to achieve aberration balance at different focal lengths, thus fulfilling the requirements of a large relative aperture, large aperture, low distortion, miniaturization, and strong environmental adaptability.

[0019] Please see Figure 1 , Figure 1 The diagrams show the structure of the miniaturized continuous zoom lens with a large target surface provided in the embodiments of the present invention in the short focal length and long focal length. The miniaturized continuous zoom lens with a large target surface provided by the present invention includes a front fixed group 10, a zoom group 20, a compensation group 30, an aperture 40, a rear fixed group 50, and a filter group 60 arranged sequentially along the light incident direction. The front fixed group 10 is used to receive incident light and complete the initial light path transmission. The aperture 40 is used to separate the compensation group 30 and the rear fixed group 50. The rear fixed group 50 is used to correct and optimize the light path. The filter group 60 is used to realize multi-mode filter switching. The zoom group 20 and the compensation group 30 are both movable along the optical axis. The zoom group 20 achieves continuous zoom function by moving along the optical axis, and the compensation group 30 cooperates with the zoom group 20 to stabilize the image plane during the zoom process by moving along the optical axis.

[0020] Specifically, this invention, through the movable arrangement of the zoom group 20 and the compensation group 30 along the optical axis, can precisely achieve continuous zoom within a focal length range of 110mm to 300mm by relying on the movement of the zoom group 20, and can also precisely coordinate with the zoom group 20 through the synchronous movement of the compensation group 30 to ensure image plane stability throughout the zoom range. At the same time, the front fixed group 10, the aperture 40, the rear fixed group 50, and the filter group 60 each perform their respective functions and work together. The front fixed group 10 lays the foundation for optical path transmission, the aperture 40 controls the amount of light entering the system, the rear fixed group 50 optimizes and corrects the optical path, and the filter group 60 meets the requirements for multi-mode filter switching. Finally, a fully functional, smooth zooming, and stable imaging optical system is formed, which is suitable for the use of large target surface high-definition imaging.

[0021] In this embodiment of the invention, the optical elements in the front fixed group 10, zoom group 20, compensation group 30, and rear fixed group 50 are all spherical lenses, and all adopt non-cemented lens structures. Specifically, the optical elements in the front fixed group 10, zoom group 20, compensation group 30, and rear fixed group 50 do not use cemented lens structures, fundamentally eliminating the delamination phenomenon that occurs in high and low temperature environments due to mismatched thermal expansion coefficients of cemented parts, effectively ensuring the lens's good environmental adaptability. Furthermore, since each lens is set as a spherical lens, there is no need for complex aspherical processing technology, which significantly saves manufacturing costs and greatly reduces the processing difficulty of the lenses, providing convenience for the mass production and application of the lens.

[0022] In this embodiment of the invention, the large-aperture miniaturized continuous zoom lens adopts a structure of negative group zoom and positive group compensation, that is: the optical power of the front fixed group 10 is positive, the optical power of the zoom group 20 is negative, the optical power of the compensation group 30 is positive, and the optical power of the rear fixed group 50 is negative. This structure is advantageous for compressing the system length by relying on a compact cam curve, while limiting the objective lens diameter of the front fixed group 10, thus meeting the requirements of lens miniaturization and weight reduction.

[0023] In this embodiment of the invention, the air gap between the front fixed group 10 and the zoom group 20 is 2.249–28.784 mm, the air gap between the zoom group 20 and the compensation group 30 is 2.5–48.918 mm, the air gap between the compensation group 30 and the aperture 40 is 1.489–21.372 mm, the air gap between the aperture 40 and the rear fixed group 50 is 4.88 mm, and the air gap between the rear fixed group 50 and the filter group 60 is 13.149 mm.

[0024] Specifically, the variable air gaps between the front fixed group 10 and the zoom group 20 (2.249–28.784 mm), the zoom group 20 and the compensation group 30 (2.5–48.918 mm), and the compensation group 30 and the aperture 40 (1.489–21.372 mm) can accommodate the movement requirements of the zoom group 20 and the compensation group 30 along the optical axis, providing the necessary optical path adjustment space for them to achieve continuous zoom function and image plane stability compensation. The fixed air gaps between the aperture 40 and the rear fixed group 50 (4.88 mm) and the rear fixed group 50 and the filter group 60 (13.149 mm) provide a stable structural reference for the rear optical path, ensuring the optical path correction and optimization effect of the rear fixed group 50 and the stability of the multi-mode filter switching of the filter group 60. Ultimately, this ensures that the lens has precise and controllable optical path and stable image quality during zooming, meeting the needs of large target surface high-definition imaging.

[0025] In this embodiment of the invention, the front fixed group 10 includes a first meniscus lens 101, a first biconvex lens 102, and a first biconcave lens 103 arranged sequentially along the incident direction of light; the zoom group 20 includes a second biconvex lens 201, a second biconcave lens 202, and a third biconcave lens 203 arranged sequentially along the incident direction of light; the compensation group 30 includes a third biconvex lens 301, a fourth biconvex lens 302, a second meniscus lens 303, a third meniscus lens 304, and a fifth biconvex lens 305 arranged sequentially along the incident direction of light; and the rear fixed group 50 includes a fourth meniscus lens 501, a fifth meniscus lens 502, a sixth biconvex lens 503, a fourth biconcave lens 504, and a sixth meniscus lens 505 arranged sequentially along the incident direction of light.

[0026] Specifically, in the front fixed group 10, the first meniscus lens 101 assists in efficiently receiving incident light, the first biconvex lens 102 enhances light convergence and initial optical path transmission, and the first biconcave lens 103 initially corrects the aberrations of the incident light, laying a solid foundation for subsequent optical path optimization; in the zoom group 20, the second biconvex lens 201 first adjusts the light convergence, and the second biconcave lens 202 and the third biconcave lens 203 work together to achieve negative optical power, providing optical support for the zoom group 20 to move along the optical axis and accurately achieve continuous zoom function; in the compensation group 30, the third biconvex lens 301 and the fourth biconvex lens 302 increase... With strong light control capabilities, the second meniscus lens 303 and the third meniscus lens 304 finely adjust the optical path offset, while the fifth biconvex lens 305 optimizes the final light convergence effect. These five elements work together to precisely compensate for image plane shift during zooming in the zoom group 20, ensuring image plane stability. In the rear fixed group 50, the fourth meniscus lens 501 and the fifth meniscus lens 502 suppress stray light and correct optical distortion, the sixth biconvex lens 503 further enhances light convergence to improve image sharpness, the fourth biconcave lens 504 balances residual aberrations, and the sixth meniscus lens 505 optimizes the optical path, ultimately achieving high-quality imaging. Each lens performs its specific function while working closely together to fully adapt to the needs of large lens apertures, continuous zoom, and high-definition imaging.

[0027] In this embodiment of the invention, the air gap between the first meniscus lens 101 and the first biconvex lens 102 is 0.3 mm; the air gap between the first biconvex lens 102 and the first biconcave lens 103 is 11.826 mm; the air gap between the first biconcave lens 103 and the second biconvex lens 201 is 2.249–28.784 mm; the air gap between the second biconvex lens 201 and the second biconcave lens 202 is 0.655 mm; the air gap between the second biconcave lens 202 and the third biconcave lens 203 is 6.553 mm; the air gap between the third biconcave lens 203 and the third biconvex lens 301 is 2.5–48.918 mm; the air gap between the third biconvex lens 301 and the fourth biconvex lens 302 is 0.3 mm; the air gap between the fourth biconvex lens 302 and the second meniscus lens 303 is 0.321 mm; the second meniscus lens 102… The air gap between the third meniscus lens 303 and the third meniscus lens 304 is 0.3 mm; the air gap between the third meniscus lens 304 and the fifth biconvex lens 305 is 0.359 mm; the air gap between the fifth biconvex lens 305 and the aperture stop 40 is 1.489–21.372 mm; the air gap between the aperture stop 40 and the fourth meniscus lens 501 is 4.88 mm; the air gap between the fourth meniscus lens 501 and the fifth meniscus lens 502 is 0.308 mm; the air gap between the fifth meniscus lens 502 and the sixth biconvex lens 503 is 8.697 mm; the air gap between the sixth biconvex lens 503 and the fourth biconcave lens 504 is 0.3 mm; the air gap between the fourth biconcave lens 504 and the sixth meniscus lens 505 is 40.928 mm; and the air gap between the sixth meniscus lens 505 and the filter group 60 is 13.149 mm.

[0028] Specifically, the lens, through precise design of the fixed and variable air gaps between the lenses and components, not only ensures that the lenses in each lens group work together to correct aberrations and stabilize the optical path, but also provides sufficient adjustment space for the zoom group 20 and the compensation group 30. At the same time, it stabilizes the reliability of the rear optical path and the switching of the filter group 60, ultimately ensuring smooth continuous zooming, clear and stable imaging, and adaptability to the needs of large target surfaces.

[0029] In this embodiment of the invention, the refractive index and Abbe number of each lens in the miniaturized continuous zoom lens with a large target surface satisfy the following conditions: 1.3 < n1 < 1.5, 1.3 < n2 < 1.5, 1.9 < n3 < 2.05, 1.85 < n4 < 2.05, 1.65 < n5 < 1.8, 1.65 < n6 < 1.8, 1.75 < n7 < 1.9, 1.5 < n8 < 1.65, 1.85 < n9 < 2.05, 1.75 < n 10 <1.95, 1.5 < n 11 <1.65, 1.75 < n 12 <1.95, 1.5 < n 13<1.65, 1.75 < n 14 <1.95, 1.75 < n 15 <1.9, 1.85 < n 16 <2.05, 1.45 < n 17 <1.6; 85<V1<95, 85<V2<95, 28<V3<35, 16<V4<20, 40<V 5<50, 40<V6<50, 33<V7<41, 61<V8<76, 16<V9<20, 38<V 10 <47, 61 <V 11 <76, 38 < V 12 <47, 61 <V 13 <76, 27 < V 14 <34, 33 < V 15 <41, 16 < V 16 <20, 57 < V 17 <71; Among them, n1, n2, n3, n4, n5, n6, n7, n8, n9, n 10 n 11 n 12 n 13 n 14 n 15 n 16 and n 17 The refractive indices of the following lenses, in sequence: first meniscus lens 101, first biconvex lens 102, first biconcave lens 103, second biconvex lens 201, second biconcave lens 202, third biconcave lens 203, third biconvex lens 301, fourth biconvex lens 302, second meniscus lens 303, third meniscus lens 304, fifth biconvex lens 305, fourth meniscus lens 501, fifth meniscus lens 502, sixth biconvex lens 503, fourth biconcave lens 504, sixth meniscus lens 505, and filter group 60; V1, V2, V3, V4, V5, V6, V7, V8, V9, V 10 V 11 V 12 V 13 V 14 V 15 V 16 and V 17The Abbe numbers of the following lenses are, in order: first meniscus lens 101, first biconvex lens 102, first biconcave lens 103, second biconvex lens 201, second biconcave lens 202, third biconcave lens 203, third biconvex lens 301, fourth biconvex lens 302, second meniscus lens 303, third meniscus lens 304, fifth biconvex lens 305, fourth meniscus lens 501, fifth meniscus lens 502, sixth biconvex lens 503, fourth biconcave lens 504, sixth meniscus lens 505, and filter group 60.

[0030] Specifically, the reasonable combination of the above-mentioned high refractive index parameters and low refractive index parameters can not only meet the core functional requirements of each lens such as light path transmission, zoom support, image plane compensation and image quality optimization, but also help the lens achieve miniaturization design; at the same time, the scientific combination of Abbe number parameters in different ranges can efficiently correct the chromatic aberration and various aberrations of the optical system and avoid imaging distortion.

[0031] In this embodiment of the invention, the filter group 60 is provided with a visible light filter, a near-infrared filter and a polarizing filter in sequence, and the filter switching is performed by a wheel structure to meet the requirements of the lens to perform high-definition imaging of the target in three modes.

[0032] In this embodiment of the invention, the front fixing group 10 can be movably arranged along the optical axis to compensate for changes in ambient temperature and the amount of image plane movement when observing close targets, thereby ensuring clear imaging.

[0033] In this embodiment of the invention, the focal length f1 of the front fixed group 10 ranges from 156mm to 192mm, providing a suitable optical basis for the efficient reception of incident light and the initial optical path transmission; the focal length f2 of the zoom group 20 ranges from -47mm to -39mm, serving as the core optical support for its continuous zoom function from 110mm to 300mm along the optical axis; the focal length f3 of the compensation group 30 ranges from 42mm to 52mm, precisely matching the zoom action of the zoom group 20, effectively offsetting image plane shift during zooming, and ensuring image plane stability; the focal length f4 of the rear fixed group 50 ranges from -371mm to -303mm, precisely correcting and optimizing the optical path transmitted by the preceding lens group, and balancing system aberrations.

[0034] In this embodiment of the invention, the miniaturized continuous zoom lens with a large target surface can be equipped with a high-resolution large target surface camera of 8984×6732 and a camera pixel size of 3.2μm, under the condition that the target surface diagonal image height is 38mm. It can not only achieve high-definition detail capture in large target surface scenes, but also effectively avoid imaging distortion by controlling the optical distortion of the large field of view to ≤2.3% and the optical distortion of the small field of view to ≤1%. Finally, it achieves a high-quality imaging effect that combines large target surface, high resolution and low distortion, which is suitable for the demanding imaging accuracy requirements of scenarios such as airborne detection.

[0035] The technical solution of the present invention will now be described in conjunction with specific embodiments.

[0036] Example 1: Please see Figure 1 This invention provides a miniaturized continuous zoom lens with a large target area, comprising a front fixed group 10, a zoom group 20, a compensation group 30, an aperture 40, a rear fixed group 50, and a filter group 60 arranged sequentially along the light incident direction; the front fixed group 10 is used to receive incident light and bear the maximum optical power, the aperture 40 is used to control the amount of light entering the system and affect the depth of field, the rear fixed group 50 is used to correct and optimize the optical path, and the filter group 60 is used to realize multi-mode filter switching; The zoom group 20 and the compensation group 30 are both movable along the optical axis. The zoom group 20 achieves continuous zoom function by moving along the optical axis, and the compensation group 30 cooperates with the zoom group 20 to stabilize the image plane during the zoom process by moving along the optical axis.

[0037] In Example 1, the optical power of the front fixed group 10 is positive, the optical power of the zoom group 20 is negative, the optical power of the compensation group 30 is positive, and the optical power of the rear fixed group 50 is negative.

[0038] In Embodiment 1, the front fixed assembly 10 includes a first meniscus lens 101, a first biconvex lens 102, and a first biconcave lens 103 arranged sequentially along the incident light direction; wherein, the first meniscus lens 101 and the first biconvex lens 102 are positive lenses with positive optical power and are both made of ultra-low dispersion material H-FK95N, which can effectively correct the secondary spectrum; the first biconcave lens 103 is a negative lens with negative optical power and is made of heavy lanthanum flint material, which can be used with low dispersion glass to achromatic and improve the ultimate resolution of the lens in the telephoto range.

[0039] In Embodiment 1, the zoom group 20 includes a second biconvex lens 201, a second biconcave lens 202, and a third biconcave lens 203 arranged sequentially along the incident direction of light. The second biconvex lens 201 is a positive lens with positive optical power and is made of a high refractive index, low Abbe number material, H-ZF88. The second biconcave lens 202 and the third biconcave lens 203 are negative lenses with negative optical power and are both made of lanthanum flint glass, which can reduce the higher aberrations of the system and is beneficial for compressing the system length.

[0040] In Embodiment 1, the compensation group 30 includes a third biconvex lens 301, a fourth biconvex lens 302, a second meniscus lens 303, a third meniscus lens 304, and a fifth biconvex lens 305 arranged sequentially along the incident direction of light. Among them, the third biconvex lens 301, the fourth biconvex lens 302, and the fifth biconvex lens 305 are all positive lenses with positive optical power, and the second meniscus lens 303 and the third meniscus lens 304 are both negative lenses with negative optical power. The third meniscus lens 304 is made of a high refractive index, low Abbe number material H-ZF88, which can cooperate with the heavy phosphorus crown material of the compensation group 30 to compensate for aberrations in the mid-focal length.

[0041] In Embodiment 1, the rear fixing group 50 includes a fourth meniscus lens 501, a fifth meniscus lens 502, a sixth biconvex lens 503, a fourth biconcave lens 504, and a sixth meniscus lens 505 arranged sequentially along the incident direction of light. Among them, the fifth meniscus lens 502, the sixth biconvex lens 503, and the sixth meniscus lens 505 are all positive lenses with positive optical power, and the fourth meniscus lens 501 and the fourth biconcave lens 504 are both negative lenses with negative optical power. The sixth meniscus lens 505 is made of high refractive index, low Abbe number material H-ZF88, and has positive optical power, which can effectively deflect light and compensate for residual aberrations at different focal lengths.

[0042] In Example 1, the optical elements of the front fixed group 10, the zoom group 20, the compensation group 30, and the rear fixed group 50 do not use cemented lens structures; wherein, the second biconvex lens 201, the second biconcave lens 202, the fourth biconvex lens 302, and the second meniscus lens 303 are separated from the cemented lens, and the air gap between the lenses is 0.3mm.

[0043] In Example 1, the focal length f1 of the front fixed group 10 ranges from 156mm to 192mm; the focal length f2 of the zoom group 20 ranges from -47mm to -39mm; the focal length f3 of the compensation group 30 ranges from 42mm to 52mm; and the focal length f4 of the rear fixed group 50 ranges from -371mm to -303mm. The zoom group 20 and the compensation group 30 are movable along the optical axis to achieve continuous zooming of the lens and maintain image plane stability throughout the entire zoom range.

[0044] In Example 1, the filter group 60 is sequentially provided with a visible light filter, a near-infrared filter, and a polarizing filter. The visible light filter, near-infrared filter, and polarizing filter are respectively H-K9L, HB720, and H-K9L. The thicknesses of the visible light filter, near-infrared filter, and polarizing filter are 2.3 mm, 2.1 mm, and 2.3 mm, respectively.

[0045] In Example 1, the front fixing group 10 is movable along the optical axis. Movement in the object direction is positive, and movement in the image direction is negative. The movement distance of the front fixing group 10 is no greater than -0.52 to 0.4 mm to compensate for changes in ambient temperature and the amount of image plane movement when observing close-range targets, ensuring clear imaging.

[0046] Please see Figure 1 When the miniaturized continuous zoom lens with a large target area provided in Embodiment 1 is in the short focal length range, the air gap between the first meniscus lens 101 and the first biconvex lens 102 is 0.3 mm; the air gap between the first biconvex lens 102 and the first biconcave lens 103 is 11.826 mm; the air gap between the first biconcave lens 103 and the second biconvex lens 201 is 2.249 mm; the air gap between the second biconvex lens 201 and the second biconcave lens 202 is 0.655 mm; the air gap between the second biconcave lens 202 and the third biconcave lens 203 is 6.553 mm; the air gap between the third biconcave lens 203 and the third biconvex lens 301 is 48.918 mm; the air gap between the third biconvex lens 301 and the fourth biconvex lens 302 is 0.3 mm; and the air gap between the fourth biconvex lens 302 and the second meniscus lens 303 is 0.32 mm. 1 mm; the air gap between the second meniscus lens 303 and the third meniscus lens 304 is 0.3 mm; the air gap between the third meniscus lens 304 and the fifth biconvex lens 305 is 0.359 mm; the air gap between the fifth biconvex lens 305 and the aperture 40 is 1.489 mm; the air gap between the aperture 40 and the fourth meniscus lens 501 is 4.88 mm; the air gap between the fourth meniscus lens 501 and the fifth meniscus lens 502 is 0.308 mm; the air gap between the fifth meniscus lens 502 and the sixth biconvex lens 503 is 8.697 mm; the air gap between the sixth biconvex lens 503 and the fourth biconcave lens 504 is 0.3 mm; the air gap between the fourth biconcave lens 504 and the sixth meniscus lens 505 is 40.928 mm; the air gap between the sixth meniscus lens 505 and the filter group 60 is 13.149 mm.

[0047] The miniaturized continuous zoom lens with a large target surface in Example 1 ensures clear imaging and image plane stability throughout the continuous zoom process by using the linear movement of the zoom group 20 along the optical axis and the nonlinear movement of the compensation group 30 along the optical axis. When the miniaturized continuous zoom lens with a large target surface provided in Example 1 zooms from a short focal length to a long focal length (110-300mm), the zoom group 20 moves 26.535mm along the side closer to the image plane, and the compensation group 30 moves 19.883mm along the side farther from the image plane.

[0048] In Example 1, the physical parameters of each lens element of the large-target miniaturized continuous zoom lens are shown in Table 1 below (wherein, the units of radius of curvature and thickness are mm, A1 is the first meniscus lens 101, A2 is the first biconvex lens 102, A3 is the first biconvex lens 102, B1 is the second biconvex lens 201, B2 is the second biconcave lens 202, B3 is the third biconcave lens 203, C1 is the third biconvex lens 301, C2 is the fourth biconvex lens 302, C3 is the second meniscus lens 303, C4 is the third meniscus lens 304, C5 is the fifth biconvex lens 305, D is the aperture stop 40, E1 is the fourth meniscus lens 501, E2 is the fifth meniscus lens 502, E3 is the sixth biconvex lens 503, E4 is the fourth biconcave lens 504, E5 is the sixth meniscus lens 505, and the filter group 60 is also shown). Table 1 Physical parameters of each lens element

[0049] Based on the above parameters, it can be seen that the focal length of the large target surface miniaturized continuous zoom lens in Example 1 is 110-300mm, the total optical length is 240mm, and the lens has a compression ratio of 0.8. It does not require the use of an additional mirror to compress the overall volume, and miniaturization is achieved only by using a straight cylindrical structure, thereby avoiding the decrease in transmittance and assembly errors introduced by the mirror.

[0050] The miniaturized continuous zoom lens with a large target surface provided in Example 1 has the following optical specifications: operating wavelength of 450–900 nm, continuous zoom focal length of 110–300 mm, image plane size of the imaging target surface of 38 mm, field of view of 7.25°–19.6°, relative aperture of 1 / 5 in both the 110 mm short focal length and the 300 mm long focal length, optical distortion of ≤2.3% in the short focal length and ≤1% in the long focal length, and an ambient temperature range of -55–70°C.

[0051] Please see Figures 2 to 5 , Figure 2 A dot plot of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the visible light band at short focal lengths. Figure 3 The transfer function diagram of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the visible light band at short focal length. Figure 4 A dot plot of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the near-infrared band at a short focal length. Figure 5 This is a transfer function diagram of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the near-infrared band at a short focal length; wherein, by Figure 2 and Figure 4As can be seen from the dot plot, the light rays from each aperture band and each field of view are focused onto the image plane in the miniaturized continuous zoom lens with a large target surface in Example 1, resulting in a relatively small spot size. Figure 3 and Figure 5 The transfer function diagram shows that the transfer function of the large-aperture miniaturized continuous zoom lens in the short focal length visible light band is >0.4 on the axis at 143 lp / mm and >0.1 across the entire field of view. This indicates that the aberrations between lens groups in the large-aperture miniaturized continuous zoom lens have been effectively corrected at short focal lengths, and the resolving power is excellent.

[0052] Please see Figures 6 to 9 , Figure 6 A dot plot of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the visible light band of the telephoto range; Figure 7 The transfer function diagram of the large-target miniaturized continuous zoom lens provided in Embodiment 1 in the visible light band of the telephoto range. Figure 8 A dot plot of the near-infrared band in the telephoto range for the miniaturized continuous zoom lens with a large target area provided in Embodiment 1. Figure 9 This is the transfer function diagram of the large-target-area miniaturized continuous zoom lens provided in Embodiment 1 in the near-infrared band at the telephoto end; wherein, by Figure 6 and Figure 8 As can be seen from the dot plot, the light rays from each aperture band and each field of view are focused onto the image plane in the miniaturized continuous zoom lens with a large target surface in Example 1, resulting in a relatively small spot size. Figure 7 and Figure 9 The transfer function diagram shows that the transfer function of the large-aperture miniaturized continuous zoom lens in the visible light band at the telephoto end is >0.4 on the axis at 143 lp / mm and >0.1 across the entire field of view. This indicates that the aberrations between lens groups in the large-aperture miniaturized continuous zoom lens have been effectively corrected at the telephoto end, and the resolving power is excellent.

[0053] Compared with the prior art, the present invention has the following advantages: First, the large target surface miniaturized continuous zoom lens provided in this embodiment of the invention has excellent high-definition imaging performance. The lens target surface diagonal image height is 38mm, which can be equipped with a large target surface camera with a resolution of 8984×6732, and the camera pixel size is 3.2μm, which fully meets the core requirements of high-definition imaging. Second, the miniaturized continuous zoom lens with a large target surface provided in this embodiment of the invention adopts a miniaturized design, is highly efficient and reliable, and has a lens compression ratio of 0.8 (the ratio of the total length TTL of the lens system to the focal length f is 0.8). It can be miniaturized by adopting a straight cylindrical structure, without the need to add an additional reflector, effectively avoiding the problems of reduced transmittance and assembly error introduced by the reflector. Third, the large target surface miniaturized continuous zoom lens provided in this embodiment of the invention has precise optical distortion control. Under the condition that the target surface diagonal image height is 38mm, the large field of view optical distortion is ≤2.3% and the small field of view optical distortion is ≤1%, resulting in high imaging accuracy. Fourth, the miniaturized continuous zoom lens with a large target surface provided in this embodiment of the invention has strong environmental adaptability. By optimizing the use of a split structure for aberration balance, the lens has no adhesive parts, which fundamentally eliminates the phenomenon of delamination caused by the mismatch of the thermal expansion coefficients of adhesive parts, and is suitable for complex and extreme working conditions.

[0054] It should be noted that all the above embodiments belong to the same inventive concept, and the descriptions of each embodiment have different focuses. Where the description in a particular embodiment is not detailed, please refer to the description in other embodiments.

[0055] The above embodiments merely illustrate implementation methods of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A large target surface miniaturized continuous zoom lens characterized by, The zoom lens comprises, in sequence along the direction of light incidence, a front fixed group, a variable magnification group, a compensation group, a diaphragm, a rear fixed group and a filter group; the front fixed group is used for receiving incident light and bears the maximum optical power; the diaphragm is used for controlling the amount of light entering the system and affecting the depth of field; the rear fixed group is used for correcting and optimizing the optical path; and the filter group is used for realizing multi-mode filter switching. The variable magnification group and the compensation group are both movably arranged along the optical axis direction; the variable magnification group realizes continuous zooming by moving along the optical axis direction; and the compensation group realizes image plane stabilization during zooming by moving along the optical axis direction in cooperation with the variable magnification group.

2. The compact zoom lens with large image surface according to claim 1, wherein The optical elements in the front fixed group, the variable magnification group, the compensation group and the rear fixed group are all spherical mirrors, and all adopt a non-cemented lens structure.

3. The compact zoom lens with large image surface according to claim 2, wherein The optical power of the front fixed group is positive, the optical power of the variable magnification group is negative, the optical power of the compensation group is positive, and the optical power of the rear fixed group is negative.

4. The compact large target size zoom lens of claim 2, wherein The air gap between the front fixed group and the variable magnification group is 2.249-28.784 mm, the air gap between the variable magnification group and the compensation group is 2.5-48.918 mm, the air gap between the compensation group and the diaphragm is 1.489-21.372 mm, the air gap between the diaphragm and the rear fixed group is 4.88 mm, and the air gap between the rear fixed group and the filter group is 13.149 mm.

5. The compact zoom lens with large image surface according to claim 4, wherein The front fixed group comprises, in sequence along the direction of light incidence, a first meniscus lens, a first biconvex lens and a first biconcave lens; the variable magnification group comprises, in sequence along the direction of light incidence, a second biconvex lens, a second biconcave lens and a third biconcave lens; the compensation group comprises, in sequence along the direction of light incidence, a third biconvex lens, a fourth biconvex lens, a second meniscus lens, a third meniscus lens and a fifth biconvex lens; and the rear fixed group comprises, in sequence along the direction of light incidence, a fourth meniscus lens, a fifth meniscus lens, a sixth biconvex lens, a fourth biconcave lens and a sixth meniscus lens.

6. The large target format miniaturized zoom lens of claim 5, wherein, The air gap from the first meniscus lens to the first double convex lens is 0.3 mm; the air gap from the first double convex lens to the first double concave lens is 11.826 mm; the air gap from the first double concave lens to the second double convex lens is 2.249-28.784 mm; the air gap from the second double convex lens to the second double concave lens is 0.655 mm; the air gap from the second double concave lens to the third double concave lens is 6.553 mm; the air gap from the third double concave lens to the third double convex lens is 2.5-48.918 mm; the air gap from the third double convex lens to the fourth double convex lens is 0.3 mm; the air gap from the fourth double convex lens to the second meniscus lens is 0.321 mm; the air gap from the second meniscus lens to the third meniscus lens is 0.3 mm; the air gap from the third meniscus lens to the fifth double convex lens is 0.359 mm; the air gap from the fifth double convex lens to the diaphragm is 1.489-21.372 mm; the air gap from the diaphragm to the fourth meniscus lens is 4.88 mm; the air gap from the fourth meniscus lens to the fifth meniscus lens is 0.308 mm; the air gap from the fifth meniscus lens to the sixth double convex lens is 8.697 mm; the air gap from the sixth double convex lens to the fourth double concave lens is 0.3 mm; the air gap from the fourth double concave lens to the sixth meniscus lens is 40.928 mm; and the air gap from the sixth meniscus lens to the filter group is 13.149 mm.

7. The large target format miniaturized zoom lens of claim 5, wherein, The refractive index and Abbe number of each lens pair in the large target surface small size continuous zoom lens satisfy the following conditions: 1.3 < n1 < 1.5, 1.3 < n2 < 1.5, 1.9 < n3 < 2.05, 1.85 < n4 < 2.05, 1.65 < n5 < 1.8, 1.65 < n6 < 1.8, 1.75 < n7 < 1.9, 1.5 < n8 < 1.65, 1.85 < n9 < 2.05, 1.75 < n 10 < 1.95, 1.5 < n 11 < 1.65, 1.75 < n 12 < 1.95, 1.5 < n 13 < 1.65, 1.75 < n 14 < 1.95, 1.75 < n 15 < 1.9, 1.85 < n 16 < 2.05, 1.45 < n 17 < 1.6; 85 < V1 < 95, 85 < V2 < 95, 28 < V3 < 35, 16 < V4 < 20, 40 < V5 < 50, 40 < V6 < 50, 33 < V7 < 41, 61 < V8 < 76, 16 < V9 < 20, 38 < V 10 < 47, 61 < V 11 < 76, 38 < V 12 < 47, 61 < V 13 < 76, 27 < V 14 < 34, 33 < V 15 < 41, 16 < V 16 < 20, 57 < V 17 < 71; n1, n2, n3, n4, n5, n6, n7, n8, n9, n 10 , n 11 , n 12 , n 13 , n 14 , n 15 , n 16 and n 17 are the refractive indices of the first meniscus lens, the first double convex lens, the first double concave lens, the second double convex lens, the second double concave lens, the third double concave lens, the third double convex lens, the fourth double convex lens, the second meniscus lens, the third meniscus lens, the fifth double convex lens, the fourth meniscus lens, the fifth meniscus lens, the sixth double convex lens, the fourth double concave lens, the sixth meniscus lens and the filter lens group, respectively; V1, V2, V3, V4, V5, V6, V7, V8, V9, V 10 , V 11 , V 12 , V 13 , V 14 , V 15 , V 16 and V 17 are the Abbe numbers of the first meniscus lens, the first double convex lens, the first double concave lens, the second double convex lens, the second double concave lens, the third double concave lens, the third double convex lens, the fourth double convex lens, the second meniscus lens, the third meniscus lens, the fifth double convex lens, the fourth meniscus lens, the fifth meniscus lens, the sixth double convex lens, the fourth double concave lens, the sixth meniscus lens and the filter lens group, respectively.

8. The large target format miniaturized continuous zoom lens of claim 1, wherein, The filter group is a filter-switchable wheel structure, and the wheel structure comprises, in sequence along a clockwise direction, a visible light filter, a near-infrared filter and a polarizer.

9. The large target format miniaturized continuous zoom lens of claim 1, wherein, The focal length f1 of the front fixed group ranges from 156 mm to 192 mm; the focal length f2 of the variable group ranges from -47 mm to -39 mm; the focal length f3 of the compensation group ranges from 42 mm to 52 mm; and the focal length f4 of the rear fixed group ranges from -371 mm to -303 mm.

10. The compact large target size zoom lens of claim 1, wherein, The large-target miniaturized continuous zoom lens can be mounted on a large-target camera with a resolution of 8984x6732 under the condition that the target surface diagonal height is 38 mm, and the large-target miniaturized continuous zoom lens can be mounted on a camera with a pixel of 3.2 μm, and the optical distortion of a large field of view is ≤2.3%, and the optical distortion of a small field of view is ≤1%.

Images