High-performance visible and long-wave infrared two-in-one optical system

Abstract

The application discloses a high-performance visible light-long-wave infrared two-light-in-one optical system, and mainly solves the problems of large volume and weight of a traditional independent visible light system and an infrared waveband optical system. The optical system comprises a main reflector, a spectral light splitting element, a visible light continuous zoom optical module and a long-wave infrared optical module. A light beam from a target object is reflected by the main reflector and reaches the spectral light splitting element, and is then divided into two paths, one of which is reflected into the visible light continuous zoom optical module, and the other is transmitted into the long-wave infrared optical module. The main reflector, the spectral light splitting element and the visible light continuous zoom optical module jointly form a visible light continuous zoom optical system and receive visible light in the light beam; and the main reflector, the spectral light splitting element and the long-wave infrared optical module jointly form a long-wave infrared optical system and receive long-wave infrared light in the light beam. The optical system can meet the requirements of long-distance high-sensitivity detection and medium-short-distance high-resolution high-contrast imaging of the target.

Description

TECHNICAL FIELD

[0001] The present application relates to multispectral photoelectric imaging system, and in particular to a high-performance visible light-long-wave infrared two-light integrated optical system, and more particularly to a multispectral integrated optical system suitable for near-range high-resolution, high-contrast imaging and long-distance high-sensitivity detection of a ground target range. BACKGROUND

[0002] With the continuous development of photoelectric technology, the demand for high-resolution, high-contrast imaging and long-distance high-sensitivity detection of the initial segment key process in the target range measurement task is becoming more and more urgent. At the same time, in order to meet the all-weather combat requirements, multiple wavebands need to be used to realize information acquisition of the target, therefore, the traditional single visible light waveband cannot meet the application requirements. At present, the visible light system and the infrared waveband system are commonly used to acquire information together, wherein the visible light system mainly relies on the sunlight reflected by the target to form an image, has high resolution and rich details, but is greatly affected by the weather, especially in the conditions of poor visibility such as fog and haze, and the combat effectiveness is easily lost. The infrared waveband system mainly relies on the self-radiation of the target to detect and image, is less affected by the weather, can work all day long, and has the advantages of high-contrast imaging and high-sensitivity detection.

[0003] However, with the increase of the detection and imaging action distance, the aperture of each system is also increasing, and the traditional two independent imaging systems have the disadvantages of large volume and heavy weight, and therefore are not conducive to the miniaturization and lightweight development of the system. SUMMARY

[0004] The present application aims to solve the technical problem of large volume and heavy weight of the traditional independent visible light system and infrared waveband optical system, and provides a high-performance visible light-long-wave infrared two-light integrated optical system.

[0005] In order to achieve the above-mentioned purpose, the technical solution provided by the present application is as follows:

[0006] A high-performance visible light-long-wave infrared two-light integrated optical system, characterized in that:

[0007] The high-performance visible light-long-wave infrared two-light integrated optical system comprises a main reflector, a spectral light splitting element, a visible light continuous zoom optical module and a long-wave infrared optical module.

[0008] The spectral light splitting element is located on the reflection light path of the main reflector, and the light beam from the target object is reflected by the main reflector to reach the spectral light splitting element and is then divided into two paths, one of which is reflected by the spectral light splitting element into the visible light continuous zoom optical module, and the other of which is transmitted by the spectral light splitting element into the long-wave infrared optical module.

[0009] The main mirror, the spectral light splitting element and the visible light continuous zoom optical module jointly constitute a visible light continuous zoom optical system for receiving visible light in the light beam;

[0010] The main mirror, the spectral light splitting element and the long-wave infrared optical module jointly constitute a long-wave infrared optical system for receiving long-wave infrared light in the light beam.

[0011] Further, the visible light continuous zoom optical module comprises a first fold mirror, a correction lens group, a second fold mirror and a visible light continuous zoom lens group arranged in sequence along a reflection light path of the spectral light splitting element; wherein the first fold mirror and the second fold mirror are respectively used for turning the light path;

[0012] The correction lens group comprises a first correction lens, a second correction lens and a third correction lens arranged in sequence along the light path; wherein the first correction lens is a meniscus heavy flint lens with negative focal power convex toward the object side; the second correction lens is a meniscus heavy crown glass with positive focal power convex toward the image side; and the third correction lens is a meniscus light crown lens with positive focal power convex toward the image side;

[0013] The visible light continuous zoom lens group comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a first cemented lens, a second cemented lens, a tenth lens, a third cemented lens, a thirteenth lens, a fourteenth lens and a fifteenth lens arranged in sequence along the light path; by adjusting the positions of the fifth lens, the first cemented lens, the second cemented lens and the tenth lens along the optical axis, the visible light continuous zoom is realized, wherein the fifth lens and the first cemented lens constitute a zoom lens group and move along the optical axis toward the image side, and the second cemented lens and the tenth lens constitute a compensation lens group and move along the optical axis toward the object side;

[0014] The first lens is a heavy flint lens with positive focal power and plano-convex;

[0015] The second lens is a heavy flint lens with negative focal power and double-concave;

[0016] The third lens is a fluor crown lens with positive focal power and double-convex;

[0017] The fourth lens is a fluor crown lens with positive focal power and double-convex;

[0018] The fifth lens is a meniscus heavy flint lens with positive focal power convex toward the object side;

[0019] The first cemented lens is a double-concave cemented lens with negative focal power, which is cemented by a sixth lens and a seventh lens; wherein the sixth lens is arranged close to the fifth lens and is a meniscus heavy flint lens with positive focal power convex toward the image side, and the seventh lens is a heavy flint lens with negative focal power and double-concave;

[0020] The second cemented lens is a biconvex cemented lens with positive focal power, which is cemented by an eighth lens and a ninth lens, wherein the eighth lens is arranged close to the seventh lens and is a meniscus heavy flint lens with negative focal power convex toward the object side, and the ninth lens is a biconvex heavy crown lens with positive focal power;

[0021] The tenth lens is a biconvex crystal lens with positive focal power;

[0022] The third cemented lens is a biconvex cemented lens with positive focal power, which is cemented by an eleventh lens and a twelfth lens, wherein the eleventh lens is arranged close to the tenth lens and is a meniscus heavy flint lens with negative focal power convex toward the object side, and the twelfth lens is a biconvex heavy flint lens with positive focal power;

[0023] The thirteenth lens is a biconcave heavy flint lens with negative focal power;

[0024] The fourteenth lens is a meniscus heavy flint lens with positive focal power convex toward the image side;

[0025] The fifteenth lens is a meniscus heavy flint lens with positive focal power convex toward the object side.

[0026] Further, the thickness of the first correction lens is 25.54 mm, the radius of curvature of the front surface is 101.33 mm, and the radius of curvature of the rear surface is 74.42 mm;

[0027] The thickness of the second correction lens is 14.00 mm, the radius of curvature of the front surface is -400.56 mm, and the radius of curvature of the rear surface is -181.49 mm;

[0028] The thickness of the third correction lens is 19.99 mm, the radius of curvature of the front surface is -56.91 mm, and the radius of curvature of the rear surface is -61.7 mm;

[0029] The thickness of the first lens is 15.00 mm, the front surface is a plane, and the radius of curvature of the rear surface is -163.00 mm;

[0030] The thickness of the second lens is 6.00 mm, the radius of curvature of the front surface is -154.10 mm, and the radius of curvature of the rear surface is 108.00 mm;

[0031] The thickness of the third lens is 18.38 mm, the radius of curvature of the front surface is 172.92 mm, and the radius of curvature of the rear surface is -192.49 mm;

[0032] The thickness of the fourth lens is 17.81 mm, the radius of curvature of the front surface is 110.70 mm, and the radius of curvature of the rear surface is -9546.83 mm;

[0033] The thickness of the fifth lens is 19.79mm, the radius of curvature of the front surface is 88.77mm, and the radius of curvature of the back surface is 113.28mm;

[0034] The thickness of the sixth lens is 19.56mm, the radius of curvature of the front surface is -356.66mm, and the radius of curvature of the back surface is -74.28mm;

[0035] The thickness of the seventh lens is 15.08mm, the radius of curvature of the front surface is -74.28mm, and the radius of curvature of the back surface is 87.29mm;

[0036] The thickness of the eighth lens is 6.20mm, the radius of curvature of the front surface is 19581.11mm, and the radius of curvature of the back surface is 80.32mm;

[0037] The thickness of the ninth lens is 11.11mm, the radius of curvature of the front surface is 80.32mm, and the radius of curvature of the back surface is -121.49mm;

[0038] The thickness of the tenth lens is 9.42mm, the radius of curvature of the front surface is 88.98mm, and the radius of curvature of the back surface is -187.54mm;

[0039] The thickness of the eleventh lens is 5.45mm, the radius of curvature of the front surface is 296.82mm, and the radius of curvature of the back surface is 36.94mm;

[0040] The thickness of the twelfth lens is 25.00mm, the radius of curvature of the front surface is 36.94mm, and the radius of curvature of the back surface is -947.764mm;

[0041] The thickness of the thirteenth lens is 25.00mm, the radius of curvature of the front surface is -83.082mm, and the radius of curvature of the back surface is 535.35mm;

[0042] The thickness of the fourteenth lens is 5.47mm, the radius of curvature of the front surface is -78.858mm, and the radius of curvature of the back surface is -54.565mm;

[0043] The thickness of the fifteenth lens is 25.00mm, the radius of curvature of the front surface is 54.217mm, and the radius of curvature of the back surface is 46.998mm.

[0044] Further, the long-wave infrared optical module comprises a third fold mirror, a fourth fold mirror, a fifth fold mirror and a long-wave infrared projection lens group arranged in sequence along the transmission light path of the spectrum splitting element; wherein the third fold mirror, the fourth fold mirror and the fifth fold mirror are respectively used for turning the light path;

[0045] The long-wave infrared projection lens comprises a first long-wave lens, a second long-wave lens, a third long-wave lens and a fourth long-wave lens arranged in sequence along an optical path.

[0046] The first long-wave lens is a positive meniscus germanium lens convex toward the object side.

[0047] The second long-wave lens is a negative meniscus germanium lens convex toward the image side.

[0048] The third long-wave lens is a negative meniscus ZnS lens convex toward the image side.

[0049] The fourth long-wave lens is a positive meniscus germanium lens convex toward the object side.

[0050] Further, the first long-wave lens is provided with a compensating lens at the light entrance end for detecting the long-wave infrared projection lens, wherein the compensating lens is a negative meniscus germanium lens convex toward the object side.

[0051] Further, the first long-wave lens has a thickness of 10.00 mm, a front surface with a curvature radius of 106.1128 mm and a back surface with a curvature radius of 355.04 mm.

[0052] The second long-wave lens has a thickness of 8.00 mm, a front surface with a non-spherical surface and a curvature radius of -117.498 mm at the vertex, and a back surface with a curvature radius of -147.996 mm.

[0053] The third long-wave lens has a thickness of 20.00 mm, a front surface with a curvature radius of -27.84 mm and a back surface with a curvature radius of -42.642 mm.

[0054] The fourth long-wave lens has a thickness of 5.00 mm, a front surface with a curvature radius of 64.325 mm and a back surface with a curvature radius of 120.0 mm.

[0055] The compensating lens has a thickness of 9.16 mm, a front surface with a curvature radius of 498.85 mm and a back surface with a non-spherical surface and a curvature radius of 163.00 mm at the vertex.

[0056] Further, the main reflector is a double curved surface with a vertex curvature radius of -1809.3 mm and a quadratic curve constant k1=-1.04; the spectral light splitting element is a positive meniscus double curved germanium lens convex toward the object side, with a thickness of 20.00 mm, a front surface with a vertex curvature radius of -815.451 mm and a quadratic curve constant k2=-3.555, and a back surface with a vertex curvature radius of -526.94 mm and a quadratic curve constant k2=-1.9.

[0057] Further, the visible light continuous zoom optical system has an aperture of 400mm, a focal length of 1500mm-3000mm, a relative aperture of 1 / 3.75-1 / 7.5, and a field of view of 0.42°-0.84°.

[0058] The long-wave infrared optical system has an aperture of 400mm, a focal length of 800mm, a relative aperture of 1 / 2, and a field of view of 0.44°.

[0059] Compared with the prior art, the present application has the following beneficial effects:

[0060] 1. The present application comprises a main reflector, a spectral splitting element, a visible light continuous zoom optical module, and a long-wave infrared optical module, wherein the main reflector, the spectral splitting element, and the visible light continuous zoom optical module together form a visible light continuous zoom optical system for receiving visible light in a light beam; and the main reflector, the spectral splitting element, and the long-wave infrared optical module together form a long-wave infrared optical system for receiving long-wave infrared light in the light beam.

[0061] 2. The visible light continuous zoom optical module of the present application comprises a first fold mirror, a correction lens group, a second fold mirror, and a visible light continuous zoom lens group arranged in sequence along an optical path, and adopts a modular design idea, so that each module can be independently assembled and detected, thereby reducing assembly difficulty, improving imaging performance, and shortening assembly cycle.

[0062] 3. The visible light continuous zoom optical system of the present application adopts a mechanical compensation type continuous zoom, and realizes visible light continuous zoom by adjusting the positions of a zoom lens group and a compensation lens group along an optical axis, thereby enhancing the applicability and flexibility of the system.

[0063] 4. The long-wave infrared optical system of the present application adopts a two-time imaging structure, realizes the conjugation of a system exit pupil and a main mirror size and the matching of the exit pupil and a detector cold shield through a long-wave infrared projection lens group, reduces self radiation of the system, solves the problem of mutual interference between the long-wave infrared and visible light systems in layout by arranging a transverse fourth fold mirror, and is more processable in focusing and camera installation.

[0064] 5、The system aims at the problem that the process of large aperture long wave infrared system is not detectable, through the method of adding compensation mirror detection in front of long wave infrared projection lens group, the performance of long wave infrared projection lens group is ensured, and the overall performance of long wave infrared system is also ensured.

[0065] 6、The application adopts a convex meniscus hyperboloid germanium lens with positive focal length towards the object side as a spectral splitting element, replaces the traditional parallel flat plate spectral splitting mode, and avoids the problems of astigmatism and ghost image caused by the flat plate spectral splitter.

[0066] 7、The application adds a first fold mirror, a second fold mirror, a third fold mirror, a fourth fold mirror and a fifth fold mirror in the optical path, greatly shortens the longitudinal size of the system, and reduces the rotation radius of the system. BRIEF DESCRIPTION OF DRAWINGS

[0067] Figure 1 It is an optical path diagram of a visible light continuous zoom long focus 3000mm optical system in the embodiment of the application.

[0068] Figure 2 It is an optical path diagram of a visible light continuous zoom short focus 1500mm optical system in the embodiment of the application.

[0069] Figure 3 It is an optical path diagram of a long wave infrared optical system in the embodiment of the application.

[0070] Figure 4 It is an optical path diagram of a long wave infrared projection lens group with a compensation mirror in the embodiment of the application.

[0071] Figure 5 It is an MTF curve diagram of a visible light continuous zoom long focus 3000mm optical system with a spatial frequency of 50lp / mm in the embodiment of the application.

[0072] Figure 6 It is an MTF curve diagram of a visible light continuous zoom short focus 1500mm optical system with a spatial frequency of 50lp / mm in the embodiment of the application.

[0073] Figure 7 It is an MTF curve diagram of a long wave infrared optical system with a spatial frequency of 33lp / mm and a focal length of 800mm in the embodiment of the application.

[0074] Figure 8 It is an MTF curve diagram of a long wave infrared compensation detection optical system with a spatial frequency of 33lp / mm in the embodiment of the application.

[0075] Figure 9 It is a spherical aberration, field curvature and distortion curve diagram of a visible light continuous zoom long focus 3000mm optical system in the embodiment of the application.

[0076] Figure 10 The ball aberration, field curvature and distortion curve diagram of the optical system with a visible light continuous zoom short focal length of 1500mm in the embodiment of the present application.

[0077] Figure 11 The ball aberration, field curvature and distortion curve diagram of the optical system with a long wave infrared focal length of 800mm in the embodiment of the present application.

[0078] The reference signs are as follows:

[0079] 1 - main reflector, 2 - spectral light splitting element, 3 - first fold mirror, 4 - second fold mirror, 5 - first corrector, 6 - second corrector, 7 - third corrector, 8 - first lens, 9 - second lens, 10 - third lens, 11 - fourth lens, 12 - fifth lens, 13 - first cemented lens, 131 - sixth lens, 132 - seventh lens, 14 - second cemented lens, 141 - eighth lens, 142 - ninth lens, 15 - tenth lens, 16 - third cemented lens, 161 - eleventh lens, 162 - twelfth lens, 17 - thirteenth lens, 18 - fourteenth lens, 19 - fifteenth lens, 20 - third fold mirror, 21 - fourth fold mirror, 22 - fifth fold mirror, 23 - first long wave lens, 24 - second long wave lens, 25 - third long wave lens, 26 - fourth long wave lens, 27 - compensator. DETAILED DESCRIPTION

[0080] The specific implementation of the present application will be further described in detail below with reference to the accompanying drawings. It should be noted that the terms "first", "second", "third", "fourth", "fifth", "sixth", "seventh", "eighth", "ninth", "tenth", "eleventh", "twelfth", "thirteenth", "fourteenth" and "fifteenth" are only used for description purposes and do not imply their relative importance.

[0081] Reference Figure 1 , Figure 2 , Figure 3 , Figure 4 The embodiment provides a high-performance visible light-long wave infrared two-light-in-one optical system, which comprises a main reflector 1, a spectral light splitting element 2, a visible light continuous zoom optical module and a long wave infrared optical module.

[0082] The spectral light splitting element 2 is located on the reflection light path of the main reflector 1, and the light beam from the target object is reflected by the main reflector 1 to reach the spectral light splitting element 2 and is then divided into two paths, one of which is reflected by the spectral light splitting element 2 into the visible light continuous zoom optical module, and the other of which is transmitted by the spectral light splitting element 2 into the long wave infrared optical module.

[0083] The main reflector 1, the spectral splitting element 2 and the visible continuous zoom optical module jointly constitute a visible continuous zoom optical system for receiving visible light in the light beam. The aperture of the visible continuous zoom optical system is 400 mm, the focal length is 1500 mm-3000 mm, the relative aperture is 1 / 3.75-1 / 7.5, and the field of view is 0.42°-0.84°. The main reflector 1, the spectral splitting element 2 and the long-wave infrared optical module jointly constitute a long-wave infrared optical system for receiving long-wave infrared light in the light beam. The aperture of the long-wave infrared optical system is 400 mm, the focal length is 800 mm, the relative aperture is 1 / 2, and the field of view is 0.44°. The high-performance visible-long-wave infrared two-light-in-one optical system has the characteristics of compact layout, small rotation radius and high detection imaging performance, and is an optical system that meets the mutual compensation of high visible light resolution and high infrared contrast high-sensitivity detection.

[0084] The main reflector 1 is a hyperboloid for aberration correction. The spectral splitting element 2 is a convex meniscus germanium lens with positive optical power towards the object side, and the splitting surface and the rear surface are both hyperboloids. The spectral splitting element 2 is a secondary reflector of the visible continuous zoom optical system and a correction mirror of the long-wave infrared optical system. The optical parameters of the spectral splitting element 2 are shown in Table 1.

[0085] Referring to Figure 1 and Figure 2 The visible continuous zoom optical module includes a first fold mirror 3, a correction mirror group, a second fold mirror 4 and a visible continuous zoom mirror group arranged in sequence along the reflection light path of the spectral splitting element 2. The first fold mirror 3 and the second fold mirror 4 are respectively used for folding the light path.

[0086] The correction mirror group includes a first correction mirror 5, a second correction mirror 6 and a third correction mirror 7 arranged in sequence along the light path. The first correction mirror 5 is a convex meniscus flint glass lens with negative optical power towards the object side. The second correction mirror 6 is a convex meniscus heavy crown glass with positive optical power towards the image side. The third correction mirror 7 is a convex meniscus light crown glass with positive optical power towards the image side. The optical parameters of each lens are shown in Table 1.

[0087] The visible continuous zoom mirror group includes a first lens 8, a second lens 9, a third lens 10, a fourth lens 11, a fifth lens 12, a first cemented lens 13, a second cemented lens 14, a tenth lens 15, a third cemented lens 16, a thirteenth lens 17, a fourteenth lens 18 and a fifteenth lens 19 arranged in sequence along the light path. The positions of the fifth lens 12, the first cemented lens 13, the second cemented lens 14 and the tenth lens 15 along the optical axis are adjusted to realize visible continuous zoom. The fifth lens 12 and the first cemented lens 13 constitute a variable magnification lens group and move towards the image side along the optical axis, and the second cemented lens 14 and the tenth lens 15 constitute a compensation lens group and move towards the object side along the optical axis.

[0088] The first lens 8 is a positive-power plano-convex heavy flint lens; the second lens 9 is a negative-power double-concave heavy flint lens; the third lens 10 is a positive-power double-convex fluorite lens; the fourth lens 11 is a positive-power double-convex fluorite lens; the fifth lens 12 is a positive-power meniscus heavy flint lens convex toward the object side; the first cemented lens 13 is a negative-power double-concave cemented lens, which is cemented by a sixth lens 131 and a seventh lens 132, wherein the sixth lens 131 is arranged close to the fifth lens 12 and is a positive-power meniscus heavy flint lens convex toward the image side, and the seventh lens 132 is a negative-power double-concave heavy flint lens; the second cemented lens 14 is a positive-power double-convex cemented lens, which is cemented by an eighth lens 141 and a ninth lens 142, wherein the eighth lens 141 is arranged close to the seventh lens 132 and is a negative-power meniscus heavy flint lens convex toward the object side, and the ninth lens 142 is a positive-power double-convex lanthanum fluoride lens; the tenth lens 15 is a positive-power double-convex crystal lens; the third cemented lens 16 is a positive-power double-convex cemented lens, which is cemented by an eleventh lens 161 and a twelfth lens 162, wherein the eleventh lens 161 is arranged close to the tenth lens 15 and is a negative-power meniscus lanthanum fluoride lens convex toward the object side, and the twelfth lens 162 is a positive-power double-convex heavy flint lens; the thirteenth lens 17 is a negative-power double-concave heavy flint lens; the fourteenth lens 18 is a positive-power meniscus heavy flint lens convex toward the image side; the fifteenth lens 19 is a positive-power meniscus heavy lanthanum fluoride lens convex toward the object side; and the optical parameters of each lens are shown in Table 1.

[0089] The long-wave infrared optical module comprises a third fold mirror 20, a fourth fold mirror 21, a fifth fold mirror 22 and a long-wave infrared projection lens group arranged in sequence along the transmission light path of the spectral splitting element 2; wherein the third fold mirror 20, the fourth fold mirror 21 and the fifth fold mirror 22 are respectively used for turning the light path, thereby reducing the radial and transverse dimensions of the system.

[0090] The long-wave infrared projection lens group comprises a first long-wave lens 23, a second long-wave lens 24, a third long-wave lens 25 and a fourth long-wave lens 26 arranged in sequence along the light path; wherein the first long-wave lens 23 is a positive-power meniscus germanium lens convex toward the object side; the second long-wave lens 24 is a negative-power meniscus germanium lens convex toward the image side; the third long-wave lens 25 is a negative-power meniscus ZnS lens convex toward the image side; and the fourth long-wave lens 26 is a positive-power meniscus germanium lens convex toward the object side; and the optical parameters of each lens are shown in Table 1.

[0091] The embodiment is directed to the problem that the process of large aperture long wave infrared system is not detectable, a compensating mirror 27 is added in front of the long wave infrared projection lens group, which is used for detecting the long wave infrared projection lens group, and the performance of the long wave infrared projection lens group is ensured, and the overall performance of the long wave infrared system is also ensured. The compensating mirror 27 is a negative focal length convex meniscus germanium lens, the thickness is 9.16mm, the curvature radius of the front surface is 498.85mm, the rear surface is aspherical, the vertex curvature radius is 163.00mm, and other parameters are shown in Table 1.

[0092] Table 1 optical parameters of each lens (unit: mm)

[0093]

[0094]

[0095]

[0096] In the table, the aspherical surface is an even spherical surface, and the aspherical surface equation is:

[0097]

[0098] Wherein, z is the aspherical surface height z coordinate, unit: mm;

[0099] r is the radial distance, unit: mm,

[0100] c is the curvature radius corresponding to;

[0101] k is the quadratic curve constant;

[0102] A is the r 4 term coefficient;

[0103] B is the r 6 term coefficient;

[0104] C is the r 8 term coefficient.

[0105] The visible light system of the embodiment is suitable for a visible light detector with a resolution of 1920x1080, a pixel pitch of 10umx10um, or a target surface diagonal size less than or equal to 22.02mm. The refrigeration type long wave infrared optical system is suitable for a refrigeration type long wave infrared thermal imager with a resolution of 640x512, a pixel pitch of 15umx15um, or a target surface diagonal size less than or equal to 12.3mm, and a cold shield F number of F2.

[0106] Figure 1 The visible light continuous zoom long focus 3000mm optical system optical path diagram is shown, Figure 2The visible light continuous zoom short focal length 1500mm optical system light path diagram is shown, the visible light continuous zoom system aperture is 400mm, the system focal length is 1500mm-3000mm continuous zoom, the relative aperture is 1 / 3.75-1 / 7.5, and the field of view is 0.42°-0.84°.

[0107] Figure 3 The long-wave infrared focal length 800mm optical system light path diagram is shown, the long-wave infrared system focal length is 800mm, the relative aperture is 1 / 2, and the field of view is 0.44°. The visible light system and the long-wave infrared system share the main reflector 1 and the spectral splitting element 2, and a special spectral splitting film is coated on the surface of the spectral splitting element 2 to divide the light path into two paths: a visible light continuous zoom system light path and a long-wave infrared system light path.

[0108] The visible light system is a secondary imaging system, which is composed of the main reflector 1, the secondary reflector spectral splitting element 2, the first fold mirror 3 and the correction lens group to form a primary imaging system. The primary imaging system images a target on a primary image plane, and then the target is imaged on the target surface of a detector through a visible light continuous zoom lens group, so that the focal length of the visible light system is continuously zoomed from 1500mm to 3000mm. The primary image system is composed of the main reflector 1, the secondary reflector (spectral splitting element 2), the first fold mirror 3 and the correction lens group, and the primary image focal length is 3220mm, the relative aperture is 1 / 8.05, and the field of view is 0.84°. The focal length of the visible light continuous zoom lens group is 100mm-200mm, the image side numerical aperture NA is 0.14-0.064, and the image side near-axis image height is 11mm.

[0109] In addition, the aperture stop of the visible light continuous zoom optical system is arranged after the compensation lens group and is conjugated with the main reflector 1. In the visible light continuous zoom optical system, the primary image system and the first lens of the visible light continuous zoom lens group form an afocal telescope system with a magnification of 14.8 times. A parallel light path is arranged after the first lens 8 of the visible light continuous zoom lens group, and an attenuation sheet can also be arranged to realize optical dimming function.

[0110] The long-wave infrared system is also a secondary imaging system, which is composed of the main reflector 1, the spectral splitting element 2, the third fold mirror 20 and the fourth fold mirror 21 to form a primary imaging system. The primary imaging system images a target on a primary image plane, and then the target is folded by the fifth fold mirror 22, is incident to a long-wave infrared projection lens group, and is finally imaged on the target surface of a long-wave infrared detector.

[0111] Figure 4 The compensation detection light path diagram of the long-wave infrared projection lens group is shown.

[0112] Figure 5 The MTF curve diagram of the visible light continuous zoom long focal length 3000mm optical system is shown, and the spatial frequency is 50lp / mm. Figure 6The shown is the optical system MTF curve diagram of visible light continuous zoom short focus 1500mm with spatial frequency 50lp / mm. Figure 7 The shown is the optical system MTF curve diagram of long wave infrared focus 800mm with spatial frequency 33lp / mm. Figure 8 The shown is the optical system MTF curve diagram of long wave infrared compensation detection light path with spatial frequency 33lp / mm. Figures 5 to 8 It can be seen that the MTF of each subsystem is close to the diffraction limit at the corresponding spatial frequency, and has high imaging quality, meeting the high resolution and high contrast imaging requirements of the system on the target.

[0113] Figures 9 to 11 The shown are the optical system spherical aberration (left), field curvature (middle) and distortion curve (right) of visible light continuous zoom system long focus 3000mm, visible light continuous zoom short focus 1500mm, long wave infrared focus 800mm, respectively. Figures 9 to 11 It can be seen that the system has small distortion, meeting the high precision measurement requirements of the system on the target.

Claims

1. A high-performance visible light-long-wave infrared dual-light combined optical system, characterized in that: Includes a primary reflector (1), a spectral splitter (2), a visible light continuous zoom optical module, and a long-wave infrared optical module; The spectral splitting element (2) is located on the reflected light path of the main reflector (1). The light beam from the target object is reflected by the main reflector (1) and then split into two paths after reaching the spectral splitting element (2). One path is reflected by the spectral splitting element (2) and enters the visible light continuous zoom optical module, while the other path is transmitted through the spectral splitting element (2) and enters the long-wave infrared optical module. The main reflector (1), the spectral splitter (2), and the visible light continuous zoom optical module together form a visible light continuous zoom optical system, which is used to receive visible light in the beam; The main reflector (1), the spectral splitter (2) and the long-wave infrared optical module together form a long-wave infrared optical system, which is used to receive long-wave infrared light in the beam. The visible light continuous zoom optical module includes a first folding mirror (3), a correction mirror group, a second folding mirror (4), and a visible light continuous zoom mirror group arranged sequentially along the reflected light path of the spectral splitting element (2); wherein the first folding mirror (3) and the second folding mirror (4) are used to bend the light path respectively. The correction lens group includes a first correction lens (5), a second correction lens (6), and a third correction lens (7) arranged sequentially along the optical path; wherein, the first correction lens (5) is a meniscus heavy flint lens with negative optical power convex towards the object side; the second correction lens (6) is a meniscus heavy phosphorus crown glass with positive optical power convex towards the image side; and the third correction lens (7) is a meniscus light crown lens with positive optical power convex towards the image side. The visible light continuous zoom lens group includes a first lens (8), a second lens (9), a third lens (10), a fourth lens (11), a fifth lens (12), a first cemented lens (13), a second cemented lens (14), a tenth lens (15), a third cemented lens (16), a thirteenth lens (17), a fourteenth lens (18), and a fifteenth lens (19) arranged sequentially along the optical path. Visible light continuous zoom is achieved by adjusting the positions of the fifth lens (12), the first cemented lens (13), the second cemented lens (14), and the tenth lens (15) along the optical axis. The fifth lens (12) and the first cemented lens (13) form a zoom lens group that moves along the optical axis toward the image plane, and the second cemented lens (14) and the tenth lens (15) form a compensating lens group that moves along the optical axis toward the object plane. The first lens (8) is a positive optical power plano-convex heavy flint lens; The second lens (9) is a negative optical power biconcave heavy flint lens; The third lens (10) is a positive optical power biconvex fluorine crown lens; The fourth lens (11) is a positive optical power biconvex fluorine crown lens; The fifth lens (12) is a meniscus heavy flint lens with positive optical power convex to the object side; The first cemented lens (13) is a negative optical power biconcave cemented lens, which is cemented together by a sixth lens (131) and a seventh lens (132). The sixth lens (131) is set close to the fifth lens (12) and is a positive optical power crescent heavy flint lens convex towards the image side. The seventh lens (132) is a negative optical power biconcave heavy flint lens. The second cemented lens (14) is a positive optical power biconvex cemented lens, which is cemented together by an eighth lens (141) and a ninth lens (142). The eighth lens (141) is set close to the seventh lens (132) and is a negative optical power object-side convex crescent heavy lanthanum flint lens. The ninth lens (142) is a positive optical power biconvex lanthanum crown lens. The tenth lens (15) is a positive optical power biconvex crystal lens; The third cemented lens (16) is a positive optical power biconvex cemented lens, which is cemented together by an eleventh lens (161) and a twelfth lens (162). The eleventh lens (161) is set close to the tenth lens (15) and is a crescent lanthanum flint lens with negative optical power facing the object side. The twelfth lens (162) is a positive optical power biconvex heavy flint lens. The thirteenth lens (17) is a negative optical power biconcave heavy flint lens; The fourteenth lens (18) is a meniscus heavy flint lens with positive optical power convex towards the image side; The fifteenth lens (19) is a meniscus heavy lanthanum flint lens with positive optical power convex to the object side.

2. The high-performance visible light-long-wave infrared dual-light combined optical system according to claim 1, characterized in that: The first correction mirror (5) has a thickness of 25.54 mm, a radius of curvature of 101.33 mm on the front surface, and a radius of curvature of 74.42 mm on the rear surface. The second correction mirror (6) has a thickness of 14.00 mm, a radius of curvature of -400.56 mm on the front surface, and a radius of curvature of -181.49 mm on the rear surface. The thickness of the third correction mirror (7) is 19.99 mm, the radius of curvature of the front surface is -56.91 mm, and the radius of curvature of the rear surface is -61.7 mm. The first lens (8) has a thickness of 15.00 mm, a flat front surface, and a radius of curvature of -163.00 mm on the rear surface. The second lens (9) has a thickness of 6.00 mm, a radius of curvature of -154.10 mm on the front surface, and a radius of curvature of 108.00 mm on the rear surface; The thickness of the third lens (10) is 18.38 mm, the radius of curvature of the front surface is 172.92 mm, and the radius of curvature of the rear surface is -192.49 mm. The fourth lens (11) has a thickness of 17.81 mm, a radius of curvature of 110.70 mm on the front surface, and a radius of curvature of -9546.83 mm on the rear surface. The fifth lens (12) has a thickness of 19.79 mm, a radius of curvature of 88.77 mm on the front surface, and a radius of curvature of 113.28 mm on the rear surface. The sixth lens (131) has a thickness of 19.56 mm, a radius of curvature of -356.66 mm on the front surface, and a radius of curvature of -74.28 mm on the rear surface. The seventh lens (132) has a thickness of 15.08 mm, a radius of curvature of -74.28 mm on the front surface, and a radius of curvature of 87.29 mm on the rear surface. The eighth lens (141) has a thickness of 6.20 mm, a radius of curvature of 19581.11 mm on the front surface, and a radius of curvature of 80.32 mm on the rear surface. The ninth lens (142) has a thickness of 11.11 mm, a radius of curvature of 80.32 mm on the front surface, and a radius of curvature of -121.49 mm on the rear surface. The tenth lens (15) has a thickness of 9.42 mm, a radius of curvature of 88.98 mm on the front surface, and a radius of curvature of -187.54 mm on the rear surface. The eleventh lens (161) has a thickness of 5.45 mm, a radius of curvature of 296.82 mm on the front surface, and a radius of curvature of 36.94 mm on the rear surface. The twelfth lens (162) has a thickness of 25.00 mm, a radius of curvature of 36.94 mm on the front surface, and a radius of curvature of -947.764 mm on the rear surface. The thirteenth lens (17) has a thickness of 25.00 mm, a radius of curvature of -83.082 mm on the front surface, and a radius of curvature of 535.35 mm on the rear surface. The fourteenth lens (18) has a thickness of 5.47 mm, a front surface radius of curvature of -78.858 mm, and a rear surface radius of curvature of -54.565 mm. The fifteenth lens (19) has a thickness of 25.00 mm, a radius of curvature of 54.217 mm on the front surface, and a radius of curvature of 46.998 mm on the rear surface.

3. The high-performance visible light-long-wave infrared dual-light combined optical system according to claim 1, characterized in that: The long-wave infrared optical module includes a third folding mirror (20), a fourth folding mirror (21), a fifth folding mirror (22) and a long-wave infrared projection mirror group arranged sequentially along the transmission optical path of the spectral splitting element (2); wherein, the third folding mirror (20), the fourth folding mirror (21) and the fifth folding mirror (22) are used to bend the optical path respectively; The long-wave infrared projection mirror group includes a first long-wave mirror (23), a second long-wave mirror (24), a third long-wave mirror (25), and a fourth long-wave mirror (26) arranged sequentially along the optical path; The first long-wave mirror (23) is a meniscus germanium lens with positive optical power convex to the object side; The second long-wave mirror (24) is a meniscus germanium lens with negative optical power convex toward the image side; The third long-wave mirror (25) is a meniscus ZnS lens with negative optical power convex towards the image side; The fourth long-wave mirror (26) is a meniscus germanium lens with positive optical power convex towards the object side.

4. The high-performance visible light-long-wave infrared dual-light combined optical system according to claim 3, characterized in that: The first long-wavelength mirror (23) is provided with a compensation mirror (27) at the light-incident end for detecting the long-wavelength infrared projection mirror group. The compensation mirror (27) is a meniscus germanium lens with negative optical power convex toward the object side.

5. The high-performance visible light-long-wave infrared dual-light combined optical system according to claim 4, characterized in that: The first long-wave mirror (23) has a thickness of 10.00 mm, a radius of curvature of 106.1128 mm on the front surface, and a radius of curvature of 355.04 mm on the rear surface. The second long-wave mirror (24) has a thickness of 8.00 mm, a front surface that is aspherical with a vertex radius of curvature of -117.498 mm, and a rear surface radius of curvature of -147.996 mm. The thickness of the third long-wave mirror (25) is 20.00 mm, the radius of curvature of the front surface is -27.84 mm, and the radius of curvature of the rear surface is -42.642 mm. The fourth long-wave mirror (26) has a thickness of 5.00 mm, a radius of curvature of 64.325 mm on the front surface, and a radius of curvature of 120.0 mm on the rear surface. The compensation mirror (27) has a thickness of 9.16 mm, a front surface radius of curvature of 498.85 mm, and a rear surface that is aspherical with a vertex radius of curvature of 163.00 mm.

6. The high-performance visible light-long-wave infrared dual-light combining optical system according to any one of claims 1 to 5, characterized in that: The primary reflector (1) is a hyperboloid with a vertex radius of curvature of -1809.3 mm and a quadratic curve constant k1 = -1.

04. The spectral splitting element (2) is a meniscus hyperboloid germanium lens with positive optical power convex to the object side. Its thickness is 20.00 mm, the vertex radius of curvature of the front surface is -815.451 mm, and the quadratic curve constant k2 = -3.555; the vertex radius of curvature of the rear surface is -526.94 mm, and the quadratic curve constant k3 = -1.

9.

7. The high-performance visible light-long-wave infrared dual-light combined optical system according to claim 6, characterized in that: The visible light continuous zoom optical system has an aperture of 400mm, a focal length of 1500mm to 3000mm, a relative aperture of 1 / 3.75 to 1 / 7.5, and a field of view of 0.42° to 0.84°. The long-wave infrared optical system has an aperture of 400mm, a focal length of 800mm, a relative aperture of 1 / 2, and a field of view of 0.44°.

Images