A multi-spectral high-resolution large-vari-focal-ratio miniaturized zoom optical system

Abstract

This invention relates to an airborne optoelectronic imaging system, specifically a multi-spectral, high-resolution, large-magnification, miniaturized zoom optical system, addressing the technical problem that existing airborne optoelectronic imaging systems cannot meet the requirements of multi-spectral, high-resolution, large-magnification, and miniaturized applications. The multi-spectral, high-resolution, large-magnification, miniaturized zoom optical system of this invention includes a front fixed group, a zoom group, a relay group, a compensation group, an image stabilization group, and a filter switching group, arranged sequentially along the optical axis from the object side to the image side. The front fixed group is fixed and used to converge the light from the target object. The zoom group, compensation group, and image stabilization group are all movable along the optical axis, used to achieve focal length changes of the optical system through the linkage of the three groups. The relay group is fixed and used to compensate for spherical aberration and coma. The filter switching group is fixed and used to provide bandpass filtering in the visible spectrum, near-infrared spectrum, and laser spectrum, respectively, to achieve detection and identification of different targets.

Description

Technical Field

[0001] This invention relates to an airborne optoelectronic imaging system, specifically to a multi-spectral high-resolution, large-magnification miniaturized zoom optical system. Background Technology

[0002] In the field of airborne optoelectronic detection, to achieve target observation and identification within a region under complex weather conditions, high-resolution, clear imaging of a designated area is typically required across different operating spectral bands to improve the probability of target observation and identification. With the continuous development of optoelectronic technology, increasingly higher demands are being placed on the operating spectral bands and identification accuracy of airborne optoelectronic detection equipment. Therefore, how to simultaneously achieve miniaturization of airborne optoelectronic detection equipment and maintain high accuracy for high-altitude reconnaissance and identification is a key research and development direction for current airborne optoelectronic detection equipment.

[0003] To meet the requirements of airborne optoelectronic detection equipment for multi-spectral and high-resolution imaging, it is necessary to propose a superior optical structure that, while meeting the size and weight requirements of airborne optoelectronic detection equipment, enables the airborne optoelectronic imaging system to have a large zoom ratio and miniaturization, thereby possessing the ability to detect and identify high-altitude targets under complex conditions. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problem that existing airborne optoelectronic imaging systems cannot meet the requirements of multi-spectral, high-resolution, large zoom ratio and miniaturization, and to provide a multi-spectral, high-resolution, large zoom ratio miniaturized zoom optical system.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A multi-band high-resolution large zoom ratio miniaturized zoom optical system is characterized by comprising a front fixed group, a zoom group, a relay group, a compensation group, an image stabilization group, and a filter switching group arranged sequentially along the optical axis from the object side to the image side.

[0007] The front fixing group is a fixed setting used to converge the light from the target object;

[0008] The zoom group, compensation group, and image stabilization group are all movable along the optical axis, and are used to achieve focal length changes of the optical system through the linkage of the three groups.

[0009] The relay group is a fixed configuration used to compensate for spherical aberration and coma.

[0010] The filter switching group is a fixed setting, used to provide bandpass filtering in the visible spectrum, near-infrared spectrum and laser spectrum respectively, so as to realize the detection and identification of different targets.

[0011] Furthermore, the front fixing group includes a first lens, a second lens, a third lens, and a fourth lens arranged sequentially along the optical axis from the object side to the image side.

[0012] The first lens of the front fixed group is a glass lens with positive optical power, and its optical power range is 0.089≤Ф. 前固定第一透镜 ≤0.094;

[0013] The second lens in the front fixed group is a glass lens with negative optical power, and its optical power range is -0.013 ≤ Ф. 前固定第二透镜 ≤-0.011;

[0014] The third lens in the front fixed group is a glass lens with positive optical power, and its optical power range is 0.005≤Ф. 前固定第三透镜 ≤0.006;

[0015] The fourth lens in the front fixed group is a glass lens with positive optical power, and its optical power range is 0.006≤Ф. 前固定第四透镜 ≤0.007.

[0016] Furthermore, the zoom group includes a first zoom group lens, a second zoom group lens, a third zoom group lens, a fourth zoom group lens, and a fifth zoom group lens arranged sequentially along the optical axis from the object side to the image side;

[0017] The first lens in the zoom group is a glass lens with negative optical power, and its optical power range is -0.032≤Ф. 变倍组第一透镜 ≤-0.027;

[0018] The second lens in the zoom group is a glass lens with positive optical power, and its optical power range is 0.036≤Ф. 变倍组第二透镜 ≤0.039;

[0019] The third lens in the zoom group is a glass lens with negative optical power, and its optical power range is -0.085≤Ф. 变倍组第三透镜 ≤-0.081;

[0020] The fourth lens in the zoom group is a glass lens with positive optical power, and its optical power range is 0.032≤Ф. 变倍组第四透镜 ≤0.035;

[0021] The fifth lens in the zoom group is a glass lens with negative optical power, and its optical power range is -0.043≤Ф. 变倍组第五透镜 ≤-0.039.

[0022] Furthermore, the relay group includes a first lens and a second lens of the relay group arranged sequentially along the optical axis from the object side to the image side;

[0023] The first lens of the relay group is a glass lens with positive optical power, and its optical power range is 0.065≤Ф. 中继组第一透镜 ≤0.071;

[0024] The second lens in the relay group is a glass lens with negative optical power, and its optical power range is -0.048 ≤ Ф. 中继组第二透镜 ≤-0.044.

[0025] Furthermore, the compensation group includes a first compensation group lens, a second compensation group lens, and a third compensation group lens arranged sequentially along the optical axis from the object side to the image side;

[0026] The first lens in the compensation group is a glass lens with positive optical power, and its optical power range is 0.0575≤Ф. 补偿组第一透镜 ≤0.062;

[0027] The second lens in the compensation group is a glass lens with negative optical power, and its optical power range is -0.052 ≤ Ф. 补偿组第二透镜 ≤-0.048;

[0028] The third lens in the compensation group is a glass lens with positive optical power, and its optical power range is 0.022≤Ф. 补偿组第三透镜 ≤0.025.

[0029] Furthermore, the image stabilization group includes a first image stabilization lens and a second image stabilization lens arranged sequentially along the optical axis from the object side to the image side;

[0030] The first lens of the image stabilization group is a glass lens with negative optical power, and its optical power range is -0.115 ≤ Ф. 稳像组第一透镜 ≤-0.100;

[0031] The second lens of the image stabilization group is a glass lens with positive optical power, and its optical power range is 0.045≤Ф. 稳像组第二透镜 ≤0.080.

[0032] Furthermore, the filter switching group includes three types of filters; the working spectral bands of the three filters are the visible spectrum band of 0.4μm to 0.65μm, the near-infrared spectrum band of 0.65μm to 0.90μm, and the laser spectrum band of 1.064μm, respectively.

[0033] Furthermore, the fourth lens of the zoom group adopts a left-curved meniscus configuration;

[0034] The fifth lens in the zoom group adopts a double concave configuration.

[0035] Furthermore, the filter switching group is a filter wheel structure.

[0036] Furthermore, the method also includes an aperture stop disposed on the side of the first lens of the relay group near the fifth lens of the zoom group.

[0037] The beneficial effects of this invention are:

[0038] 1. The present invention discloses a multi-spectral high-resolution large zoom ratio miniaturized zoom optical system, which adopts a transmission-type three-group linkage optical structure, namely a moving zoom group, a compensation group, and an image stabilization group, to realize the focal length variation and reduce the size of the optical system. It has the advantages of large zoom ratio, miniaturization, and high resolution in three working spectrum bands: visible light, near infrared and laser, thus meeting the requirements of airborne optoelectronic imaging systems for multi-spectral, high-resolution, large zoom ratio and miniaturization.

[0039] 2. The present invention discloses a multi-band high-resolution large zoom ratio miniaturized zoom optical system, which consists of six parts: a front fixed group, a zoom group, a relay group, a compensation group, an image stabilization group, and a filter switching group. It can meet the requirements of image plane with a resolution of 1920×1080, a focal length range of 10mm to 350mm, a zoom ratio of 35x, and a ratio of 2 between the telephoto focal length (350mm) and the optical length (175mm).

[0040] 3. The present invention provides a multi-spectral high-resolution large zoom ratio miniaturized zoom optical system. The zoom group, compensation group and image stabilization group all use glass lenses, which can clearly image in the visible spectrum (0.4μm~0.65μm), near-infrared spectrum (0.65μm~0.9μm) and laser spectrum (1.064μm), thus improving the ability to observe targets.

[0041] 4. The present invention provides a multi-spectral high-resolution large zoom ratio miniaturized zoom optical system, which can achieve high-resolution clear imaging in visible light, near-infrared and laser light, meeting the requirements for all-weather use and the ability to observe laser spot. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of an embodiment of a multi-spectral high-resolution large zoom ratio miniaturized zoom optical system according to the present invention;

[0043] Figure 2(a) is a schematic diagram of the structure of a multi-band high-resolution large zoom ratio miniaturized zoom optical system embodiment of the present invention in the short focal length state in the visible spectrum.

[0044] Figure 2(b) is a modulation transfer function diagram of Figure 2(a);

[0045] Figure 2(c) is the field curvature / distortion diagram of Figure 2(a);

[0046] Figure 2(d) is a dot plot of Figure 2(a);

[0047] Figure 2(e) is a relative illumination map of Figure 2(a);

[0048] Figure 3(a) is a schematic diagram of the mid-focus state structure of an embodiment of a multi-band high-resolution large zoom ratio miniaturized zoom optical system of the present invention in the visible spectrum band.

[0049] Figure 3(b) is a modulation transfer function diagram of Figure 3(a);

[0050] Figure 3(c) is the field curvature / distortion diagram of Figure 3(a);

[0051] Figure 3(d) is a dot plot of Figure 3(a);

[0052] Figure 3(e) is the relative illumination map of Figure 3(a);

[0053] Figure 4(a) is a schematic diagram of the structure of a multi-band high-resolution large zoom ratio miniaturized zoom optical system according to the present invention in the long focal length state in the visible spectrum band.

[0054] Figure 4(b) is a modulation transfer function diagram of Figure 4(a);

[0055] Figure 4(c) is the field curvature / distortion diagram of Figure 4(a);

[0056] Figure 4(d) is a dot plot of Figure 4(a);

[0057] Figure 4(e) is a relative illumination map of Figure 4(a);

[0058] Figure 5(a) is a schematic diagram of the structure of a multi-band high-resolution large zoom ratio miniaturized zoom optical system according to the present invention in the short focal length state in the near-infrared band.

[0059] Figure 5(b) is a modulation transfer function diagram of Figure 5(a);

[0060] Figure 5(c) is the field curvature / distortion diagram of Figure 5(a);

[0061] Figure 5(d) is a point plot of Figure 5(a);

[0062] Figure 5(e) is a relative illumination map of Figure 5(a);

[0063] Figure 6(a) is a schematic diagram of the mid-focus state structure of an embodiment of a multi-band high-resolution large zoom ratio miniaturized zoom optical system of the present invention in the near-infrared band.

[0064] Figure 6(b) is a modulation transfer function diagram of Figure 6(a);

[0065] Figure 6(c) is the field curvature / distortion diagram of Figure 6(a);

[0066] Figure 6(d) is a point plot of Figure 6(a);

[0067] Figure 6(e) is a relative illumination map of Figure 6(a);

[0068] Figure 7(a) is a schematic diagram of the structure of a multi-band high-resolution large zoom ratio miniaturized zoom optical system according to the present invention in the long focal length state in the near-infrared band.

[0069] Figure 7(b) is a modulation transfer function diagram of Figure 7(a);

[0070] Figure 7(c) is the field curvature / distortion diagram of Figure 7(a);

[0071] Figure 7(d) is a point plot of Figure 7(a);

[0072] Figure 7(e) is a relative illumination map of Figure 7(a);

[0073] Figure 8(a) is a schematic diagram of the structure of an embodiment of a multi-band high-resolution large zoom ratio miniaturized zoom optical system of the present invention in the laser spectral band of 1.064μm;

[0074] Figure 8(b) is a schematic diagram of the modulation transfer function in Figure 8(a);

[0075] Figure 8(c) is a dot plot of Figure 8(a).

[0076] Explanation of reference numerals in the attached diagram: 1-Front fixed group, 11-First lens of the front fixed group, 12-Second lens of the front fixed group, 13-Third lens of the front fixed group, 14-Fourth lens of the front fixed group, 2-Magnification group, 21-First lens of the magnification group, 22-Second lens of the magnification group, 23-Third lens of the magnification group, 24-Fourth lens of the magnification group, 25-Fifth lens of the magnification group, 3-Relay group, 31-First lens of the relay group, 32-Second lens of the relay group, 4-Compensation group, 41-First lens of the compensation group, 42-Second lens of the compensation group, 43-Third lens of the compensation group, 5-Image stabilization group, 51-First lens of the image stabilization group, 52-Second lens of the image stabilization group, 6-Filter switching group. Detailed Implementation

[0077] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0078] like Figure 1As shown, a multi-spectral, high-resolution, large-magnification-ratio miniaturized zoom optical system includes a front fixed group 1, a zoom group 2, a relay group 3, a compensation group 4, an image stabilization group 5, and a filter switching group 6 arranged sequentially along the optical axis from the object side to the image side. The front fixed group 1 is fixed and used to converge the spatial light rays of the target object and collect the spatial energy of the target object. The zoom group 2, compensation group 4, and image stabilization group 5 move together to realize the focal length change of the system of the present invention. The relay group 3 is fixed and used to correct the residual aberrations and coma after passing through the front fixed group 1 and zoom group 2, improve the focal length change range, reduce the volume, and compensate for the residual aberrations. The filter switching group 6 is fixed and used to provide bandpass filtering in the visible spectrum, near-infrared spectrum, and laser spectrum respectively to realize the detection and identification of different targets.

[0079] The front fixed group 1 includes a first lens 11, a second lens 12, a third lens 13, and a fourth lens 14 arranged sequentially along the optical axis from the object side to the image side. The first lens 11 is a spherical glass lens with positive optical power, which can effectively reduce chromatic aberration, improve image quality, and converge incoming light, reducing the light beam height. The second lens 12 is a spherical glass lens with negative optical power, which can improve the ability of the second lens 12 to correct the path of light, meeting the requirements for converging light at large angles. Both the first lens 11 and the second lens 12 mainly realize the spherical aberration correction of the system at long focal lengths and the distortion correction at short focal lengths. The third lens 13 is a spherical glass lens with positive optical power, which can effectively reduce chromatic aberration and improve image quality. The fourth lens 14 is a spherical glass lens with positive optical power, which can further converge the light entering the zoom group 2, reducing the aperture of the zoom group 2 and its subsequent groups.

[0080] The zoom group 2 comprises, along the optical axis from the object side to the image side, a first zoom group lens 21, a second zoom group lens 22, a third zoom group lens 23, a fourth zoom group lens 24, and a fifth zoom group lens 25, arranged sequentially. The first zoom group lens 21 is a spherical glass lens with negative optical power. This lens is used to diverge the light rays converged by the pre-fixed group 1 and to provide correction for distortion and coma. The second zoom group lens 22 is a spherical glass lens with positive optical power. This lens is used to converge the light rays diverged by the first zoom group lens 21 and, together with the first zoom group lens 21, provides correction for spherical aberration and distortion. The third zoom group lens 23 is a spherical glass lens with negative optical power. This lens adopts a biconcave configuration, which is beneficial for light rays to travel at relatively low focal lengths from telephoto to short focal lengths. The incident angle is relatively flat as light enters the lens and subsequent lenses, reducing the tolerance sensitivity of the system of the present invention; the fourth lens 24 of the zoom group is a spherical glass lens with positive optical power. This lens adopts a left-curved meniscus configuration, which helps to reduce the tolerance sensitivity of the lens and converge the light height of each field of view. This lens, together with the third lens 23 of the zoom group, provides spherical aberration correction; the fifth lens 25 of the zoom group is a spherical glass lens with negative optical power. This lens adopts a biconcave configuration, which helps light enter the aperture stop and relay group 3 with a smaller incident angle, reducing tolerance sensitivity.

[0081] The relay group 3 includes a first lens 31 and a second lens 32 arranged sequentially along the optical axis from the object side to the image side. The first lens 31 is a spherical glass lens with positive optical power, used to converge the light rays converged by the front fixed group 1 and the zoom group 2. The second lens 32 is a spherical glass lens with negative optical power, used to diverge the light rays converged by the first lens 31, and together with the first lens 21 of the zoom group, provides positive optical power to achieve light convergence and correction of residual spherical aberration and coma. An aperture stop is provided on the side of the first lens 31 near the fifth lens 25 of the zoom group.

[0082] The compensation group 4 includes a first lens 41, a second lens 42, and a third lens 43 arranged sequentially along the optical axis from the object side to the image side. The first lens 41 is a spherical glass lens 5 with positive optical power, which is used to converge the light rays from the relay group 3; the second lens 42 is a spherical glass lens with negative optical power, which is used to diverge the light rays converged by the first lens 31 of the relay group, and together with the first lens 41, provides correction for spherical aberration and coma; the third lens 43 is a spherical glass lens with positive optical power, which is used to converge the light rays to the image stabilization group 5.

[0083] The image stabilization group 5 includes a first lens 51 and a second lens 52 arranged sequentially along the optical axis from the object side to the image side. The first lens 51 is a spherical glass lens with negative optical power, which is used to diverge the light rays converged by the front fixing group 1, the zoom group 2, the relay group 3, and the compensation group 4; the second lens 52 is a spherical glass lens with positive optical power, which is used to converge the light rays diverged by the first lens 51 and achieve a clear image on the image plane.

[0084] The filter switching group 6 contains three types of filters, which can be switched between different working spectrum bands through a filter wheel structure. The working spectrum bands of the three filters are the visible spectrum band of 0.4μm to 0.65μm, the near-infrared spectrum band of 0.65μm to 0.90μm, and the laser spectrum band of 1.064μm.

[0085] In this embodiment, the front fixed group 1 consists of four lenses, used to converge the spatial light of the target object and collect the spatial energy of the target object into the zoom group 2. The zoom group 2, relay group 3, and compensation group 4 provide focal length variation, enabling the system of this invention to achieve clear imaging capabilities from short focal length (10mm), medium focal length (180mm) to long focal length (350mm), with a 35x focal length variation, better meeting the needs of reconnaissance and identification tasks. The image stabilization group 5 compensates for aberrations caused by focal length variations and provides a certain focal length variation, expanding the system's zoom ratio. The filter switching group 6 provides bandpass filtering in the visible spectrum, near-infrared spectrum, and laser spectrum, respectively, thereby enabling the detection and identification of different targets. In this embodiment, the parameters of the front fixed group 1, zoom group 2, relay group 3, compensation group 4, and image stabilization group 5 are detailed in Table 1.

[0086] Table 1

[0087]

[0088]

[0089] In the table above, the intervals D1 between the front fixed group 1 and the zoom group 2, D4 between the zoom group 2 and the relay group 3, D7 between the relay group 3 and the compensation group 4, D10 between the compensation group 4 and the image stabilization group 5, and D13 between the image stabilization group 5 and the filter switching group 6 form the short focal length state of the optical system; the intervals D2 between the front fixed group 1 and the zoom group 2, D5 between the zoom group 2 and the relay group 3, D8 between the relay group 3 and the compensation group 4, D11 between the compensation group 4 and the image stabilization group 5, and D14 between the image stabilization group 5 and the filter switching group 6 form the medium focal length state of the optical system; and the intervals D3 between the front fixed group 1 and the zoom group 2, D6 between the zoom group 2 and the relay group 3, D9 between the relay group 3 and the compensation group 4, D12 between the compensation group 4 and the image stabilization group 5, and D15 between the image stabilization group 5 and the filter switching group 6 form the long focal length state of the optical system.

[0090] As shown in Figure 2(a), by moving zoom group 2, compensation group 4, and image stabilization group 5, a short focal length (10mm) is obtained in the visible spectrum (0.4μm~0.65μm). The modulation transfer function (MTF) is shown in Figure 2(b), where the vertical direction represents contrast and the horizontal direction represents spatial frequency. From the curves in Figure 2(b), it can be seen that the MTF values ​​for each field of view are all above 0.2 at a frequency of 145lp / mm, indicating good contrast in the short focal length within the visible spectrum, which meets application requirements. The field curvature / distortion is shown in Figure 2(c), where the vertical direction represents the field of view, the left graph shows the horizontal distance from the focal plane to the paraxial focal plane, and the right graph shows the distortion percentage. From the curves in Figure 2(c), it can be seen that within the field of view, the field curvature aberration is controlled within (-0.2mm, +0.2mm), and the distortion is controlled within 3%. This indicates that the short focal field curvature and distortion in the visible spectrum are well controlled, with low distortion levels, meeting application requirements. The dot plot is shown in Figure 2(d). Figure 2(d) shows that the dot patterns formed within each field of view are relatively round, without obvious tailing, and the spectral bands converge and concentrate without obvious color separation. Numerically, the radius of the diffuse spot is smaller than the Airy disk radius (3.944 μm) within a 0.5 field of view, indicating high energy concentration, meeting application requirements. The relative illuminance diagram is shown in Figure 2(e), where the vertical direction represents the percentage of relative illuminance, and the horizontal direction represents the image plane size. The curve in Figure 2(e) shows that the relative illuminance does not change significantly across the entire field of view and is consistently above 98%, indicating good image plane illuminance uniformity, meeting application requirements.

[0091] As shown in Figure 3(a), by moving zoom group 2, compensation group 4, and image stabilization group 5, the mid-focus state (focal length 180mm) in the visible spectrum (0.4μm~0.65μm) can be obtained. Its modulation transfer function (MTF) is shown in Figure 3(b), where the vertical direction represents contrast and the horizontal direction represents spatial frequency. From the curves in Figure 3(b), it can be seen that the MTF values ​​for each field of view are all higher than 0.2 at a frequency of 145lp / mm. The MTF curve for the 0-field view is close to the diffraction limit, indicating that the mid-focus in the visible spectrum has good contrast, which can meet application requirements. The field curvature / distortion diagram is shown in Figure 3(c). The vertical direction represents the field of view, the horizontal direction in the left diagram represents the distance from the focal plane to the paraxial focal plane, and the right diagram represents the distortion percentage. From the curves in the figure, it can be seen that within the field of view, the field curvature aberration value is controlled within (-0.1mm, +0.1mm), and the distortion is controlled within 0.1%. This indicates that the field curvature and distortion in the visible spectrum are well controlled, with low distortion levels, meeting application requirements. Figure 3(d) shows a dot plot. It can be seen that the dot patterns formed within each field of view are relatively round, without obvious tailing, and the spectral bands converge and concentrate without obvious color separation. Numerically, the radius of the diffuse spot is smaller than the Airy disk radius (3.662 μm) within a 0.5 field of view, indicating high energy concentration, meeting application requirements. Figure 3(e) is a relative illuminance diagram. The vertical direction represents the percentage of relative illuminance, and the horizontal direction represents the image plane size. The curve in Figure 3(e) shows that the relative illuminance does not change significantly across the entire field of view and is consistently above 95%, indicating good image plane illuminance uniformity, meeting application requirements.

[0092] As shown in Figure 4(a), by moving the zoom group 2, compensation group 4, and image stabilization group 5, the telephoto state (focal length 350mm) in the visible spectrum (0.4μm~0.65μm) of this embodiment of the invention can be obtained. Figure 4(b) is a modulation transfer function (MTF) graph, with the vertical direction representing contrast and the horizontal direction representing spatial frequency. From the curves in the figure, it can be seen that the MTF values ​​for each field of view are all higher than 0.2 at a frequency of 145lp / mm, with the 0-field-of-view MTF curve approaching the diffraction limit, indicating that the telephoto lens in the visible spectrum has good contrast and can meet application requirements. Figure 4(c) is a field curvature / distortion graph, with the vertical direction representing the field of view, the horizontal direction in the left graph representing the distance from the focal plane to the paraxial focal plane, and the right graph representing the distortion percentage. From the curves in Figure 4(c), it can be seen that within the field of view, the field curvature aberration value is controlled within (-0.5mm, +0.5mm), and the distortion is controlled within 0.3%. This indicates that the field curvature and distortion in the visible spectrum are well controlled, with no significant distortion, meeting application requirements. Figure 4(d) is a dot plot. The graph in Figure 4(d) shows that the dot patterns formed within each field of view are relatively round, without significant tailing, and the spectral bands converge and concentrate without obvious color separation. Numerically, the radius of the diffuse spot is smaller than the Airy disk radius (4.33 μm) within a 0.5 field of view, indicating high energy concentration, meeting application requirements. Figure 4(e) is a relative illuminance diagram. The vertical direction represents the percentage of relative illuminance, and the horizontal direction represents the image plane size. The curve in Figure 4(e) shows slight variations in relative illuminance across the entire field of view, all above 90%, indicating good image plane illuminance uniformity, meeting application requirements.

[0093] As shown in Figure 5(a), by moving zoom group 2, compensation group 4, and image stabilization group 5, a short focal length (10mm) is obtained in the near-infrared spectral band (0.65μm~0.90μm). Figure 5(b) shows the modulation transfer function (MTF) graph, with the vertical direction representing contrast and the horizontal direction representing spatial frequency. The curves in the figure show that the MTF values ​​for each field of view are all above 0.3 at a frequency of 30lp / mm, indicating that the short focal length in the near-infrared spectral band has good low-frequency contrast, ensuring good fog-penetrating observation capability. Figure 5(c) shows the field curvature / distortion graph, with the vertical direction representing the field of view, the horizontal direction in the left graph representing the distance from the focal plane to the paraxial focal plane, and the right graph representing the distortion percentage. The curves in the figure show that within the field of view, the field curvature aberration is controlled within (-0.5mm, +0.5mm), and the distortion is controlled within 3%. This indicates that the short focal field curvature and distortion in the visible spectrum are well controlled, with low distortion levels, meeting application requirements. Figure 5(d) is a dot plot. The graph shows that the dot patterns formed within each field of view are relatively round, without obvious tailing, and the spectral bands converge and are concentrated without obvious color separation. Numerically, the radius of the diffuse spot is smaller than the Airy disk radius (5.585 μm) within a 0.7 field of view, indicating high energy concentration, meeting application requirements. Figure 5(e) is a relative illumination diagram. The vertical direction represents the percentage of relative illumination, and the horizontal direction represents the image plane size. The curves in the figure show that the relative illumination does not change significantly across the entire field of view and is consistently above 98%, indicating good image plane illumination uniformity, meeting application requirements.

[0094] As shown in Figure 6(a), by moving zoom group 2, compensation group 4, and image stabilization group 5, a mid-focus state (focal length 180mm) in the near-infrared spectral band (0.65μm~0.90μm) can be obtained. Figure 6(b) is a modulation transfer function (MTF) diagram, with the vertical direction representing contrast and the horizontal direction representing spatial frequency. The curves in the figure show that the MTF values ​​for each field of view are all above 0.3 at a frequency of 30lp / mm, indicating that the low-frequency information in the mid-focus area of ​​the near-infrared spectral band is well preserved, ensuring good fog-penetrating observation capability. Figure 6(c) is a field curvature / distortion diagram, with the vertical direction representing the field of view, the horizontal direction in the left figure representing the distance from the focal plane to the paraxial focal plane, and the right figure representing the distortion percentage. The curves in the figure show that within the field of view, the field curvature aberration value is controlled within (-0.1mm, +0.1mm), and the distortion is controlled within 0.1%. This indicates that the field curvature and distortion in the visible spectrum are well controlled, with low distortion levels, meeting application requirements. Figure 6(d) is a dot plot. The graph shows that the dot patterns formed within each field of view are relatively round, without obvious tailing or color separation. Numerically, the radius of the diffuse spot within the field of view is slightly larger than the Airy disk radius (5.213 μm), indicating a slight decrease in energy concentration. However, the convergence of light at different wavelengths in the near-infrared spectrum remains relatively consistent, meeting the imaging requirements for black and white images in the near-infrared band. Figure 6(e) is a relative illumination diagram. The vertical direction represents the percentage of relative illumination, and the horizontal direction represents the image plane size. The curves in the figure show that the relative illumination does not change significantly across the entire field of view and is consistently above 95%, indicating good image plane illumination uniformity, meeting application requirements.

[0095] As shown in Figure 7(a), by moving zoom group 2, compensation group 4, and image stabilization group 5, a telephoto state (focal length 350mm) in the near-infrared spectral band (0.65μm~0.90μm) can be obtained. Figure 7(b) is a modulation transfer function (MTF) graph, with the vertical direction representing contrast and the horizontal direction representing spatial frequency. The curves in the graph show that the MTF values ​​for each field of view are all above 0.2 at a frequency of 30lp / mm, indicating that the mid-to-low frequency information in the near-infrared spectral band is well preserved, ensuring good fog-penetrating observation capability. Figure 7(c) is a field curvature / distortion graph, with the vertical direction representing the field of view, the horizontal direction in the left graph representing the distance from the focal plane to the paraxial focal plane, and the right graph representing the distortion percentage. The curves in the graph show that within the field of view, the field curvature aberration is controlled within (-0.5mm, +0.5mm), and the distortion is controlled within 0.3%. This indicates that the field curvature and distortion in the visible spectrum are well controlled, with low distortion levels, meeting application requirements. Figure 7(d) shows that the dot pattern formed in each field of view is relatively round, without obvious tailing or color separation. Numerical data shows that the radius of the diffuse spot is basically consistent across all fields of view, indicating uniform imaging sharpness across the entire field of view.

[0096] Figure 7(e) shows the relative illumination diagram. The vertical direction represents the percentage of relative illumination, and the horizontal direction represents the image plane size. As can be seen from the curves in the figure, there are slight variations in relative illumination across the entire field of view, all of which are above 90%, indicating that the image plane illumination uniformity is good and can meet the application requirements.

[0097] As shown in Figure 8(a), by moving zoom group 2, compensation group 4, and image stabilization group 5, a long focal length (focal length 350mm) in the laser spectrum (1.064μm) can be obtained. Figure 8(b) shows the modulation transfer function (MTF) graph, with the vertical direction representing contrast and the horizontal direction representing spatial frequency. The curves in the graph show that the MTF values ​​for each field of view are all above 0.3 at a frequency of 50lp / mm, indicating that the long focal length image in the laser spectrum maintains a high level of contrast, allowing for observation of the target environment while simultaneously observing the laser spot. Figure 8(c) shows the dot pattern. The graph shows that the dot patterns formed in each field of view are relatively round with no obvious trailing. The radius of the diffuse spots is basically consistent across each field of view, indicating that the imaging sharpness is basically consistent across the entire field of view.

Claims

1. A multi-spectral, high-resolution, large-magnification, miniaturized zoom optical system, characterized in that: It includes a front fixing group (1), a zoom group (2), a relay group (3), a compensation group (4), an image stabilization group (5), and a filter switching group (6) arranged sequentially from the object side to the image side along the optical axis; The front fixing group (1) is fixedly installed and used to converge the light of the target object; The zoom group (2), compensation group (4) and image stabilization group (5) are all movable along the optical axis, and are used to realize the focal length change of the optical system through the linkage of the three groups; The relay group (3) is fixed and is used to compensate for spherical aberration and coma. The filter switching group (6) is fixed and is used to provide bandpass filtering in the visible spectrum, near-infrared spectrum and laser spectrum respectively, so as to realize the detection and identification of different targets; The filter switching group (6) includes three types of filters; the working spectral bands of the three types of filters are the visible spectrum band of 0.4μm~0.65μm, the near-infrared spectrum band of 0.65μm~0.90μm and the laser spectrum band of 1.064μm, respectively. The filter switching group (6) is a filter wheel structure; The image stabilization group (5) includes a first lens (51) and a second lens (52) arranged sequentially along the optical axis from the object side to the image side; The first lens (51) of the image stabilizing group is a glass lens having a negative refractive power, and the range of the refractive power is -0.115≤Φ 稳像组第一透镜 ≤-0.

100. The second lens (52) of the image stabilizing group is a glass lens having positive refractive power, with a refractive power range of 0.045≤Ф 稳像组第二透镜 ≤0.

080.

2. The multi-band high-resolution large zoom ratio miniaturized zoom optical system according to claim 1, characterized in that: The front fixing group (1) includes a first lens (11), a second lens (12), a third lens (13), and a fourth lens (14) arranged sequentially along the optical axis from the object side to the image side. The first lens (11) of the front fixing group is a glass lens with positive focal power, whose focal power range is 0.089≤Ф 前固定第一透镜 ≤0.094; The second lens (12) of the front fixed group is a glass lens with negative optical power, whose optical power ranges from -0.013≤Φ 前固定第二透镜 ≤-0.011; The third lens (13) of the front fixed group is a glass lens with positive refractive power, whose refractive power ranges from 0.005≤Ф 前固定第三透镜 ≤0.006; The fourth lens (14) of the front fixed group is a glass lens with positive refractive power, whose refractive power ranges from 0.006≤Ф 前固定第四透镜 ≤0.

007.

3. The multi-band high-resolution large zoom ratio miniaturized zoom optical system according to claim 2, characterized in that: The zoom group (2) includes a first zoom group lens (21), a second zoom group lens (22), a third zoom group lens (23), a fourth zoom group lens (24), and a fifth zoom group lens (25) arranged sequentially from the object side to the image side along the optical axis; The first lens (21) of the zoom group is a glass lens with negative optical power, and its optical power range is -0.032≤Ф. 变倍组第一透镜 ≤-0.027; The second lens (22) of the zoom group is a glass lens with positive optical power, and its optical power range is 0.036≤Ф. 变倍组第二透镜 ≤0.039; The third lens (23) of the zoom group is a glass lens with negative optical power, and its optical power range is -0.085≤Ф. 变倍组第三透镜 ≤-0.081; The fourth lens (24) of the zoom group is a glass lens with positive optical power, and its optical power range is 0.032≤Ф. 变倍组第四透镜 ≤0.035; The fifth lens (25) of the zoom group is a glass lens with negative optical power, and its optical power range is -0.043≤Ф. 变倍组第五透镜 ≤-0.

039.

4. The multi-band high-resolution large zoom ratio miniaturized zoom optical system according to claim 3, characterized in that: The relay group (3) includes a first lens (31) and a second lens (32) arranged sequentially along the optical axis from the object side to the image side; The first lens (31) of the relay group is a glass lens with positive optical power, and its optical power range is 0.065≤Ф. 中继组第一透镜 ≤0.071; The second lens (32) of the relay group is a glass lens with negative optical power, and its optical power range is -0.048≤Ф. 中继组第二透镜 ≤-0.

044.

5. The multi-band high-resolution large zoom ratio miniaturized zoom optical system according to claim 4, characterized in that: The compensation group (4) includes a first compensation group lens (41), a second compensation group lens (42), and a third compensation group lens (43) arranged sequentially along the optical axis from the object side to the image side; The first lens (41) of the compensation group is a glass lens with positive optical power, and its optical power range is 0.0575≤Ф. 补偿组第一透镜 ≤0.062; The second lens (42) of the compensation group is a glass lens with negative optical power, and its optical power range is -0.052≤Ф. 补偿组第二透镜 ≤-0.048; The third lens (43) of the compensation group is a glass lens with positive optical power, and its optical power range is 0.022≤Ф. 补偿组第三透镜 ≤0.

025.

6. The multi-band high-resolution large zoom ratio miniaturized zoom optical system according to claim 3, characterized in that: The fourth lens (24) of the zoom group adopts a left crescent configuration; The fifth lens (25) of the zoom group adopts a double concave configuration.

7. The multi-band high-resolution large zoom ratio miniaturized zoom optical system according to claim 6, characterized in that: It also includes an aperture located on the side of the first lens (31) of the relay group near the fifth lens (25) of the zoom group.

Images