A multi-aperture lobster-eye optical system

Abstract

The present invention provides a multi-aperture lobster-eye optical system. Compared with the traditional lobster-eye optical system, the new lobster-eye optical system significantly increases the number of light spot arms. This improvement significantly reduces the difficulty of imaging positioning in the edge field of view and improves the accuracy and reliability of positioning. In addition, a central aperture optical subsystem is placed in the center to image the target object, which can improve the problem that the lobster-eye optical system itself cannot clearly image the target. Overall, the diamond-shaped lobster-eye lens of the present invention shows obvious advantages in both imaging performance and practical applications. It not only significantly reduces the difficulty of imaging positioning in the edge field of view and improves the accuracy and reliability of positioning, but also can maintain the original imaging clarity and detail performance when the angle between the diamond-shaped lobster-eye lens and the detector changes, and the imaging quality is highly stable.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical elements, and in particular relates to a multi-aperture lobster-eye optical system. Background Art

[0002] In traditional high-performance imaging optical systems, to achieve both a wide field of view and high image quality, the existing approach is to increase the system's entrance pupil diameter to reduce the F-number. This approach can improve the system's resolution and operating range, but it also leads to increased costs and system complexity. Specifically, to reduce off-axis aberrations such as astigmatism and chromatic aberration caused by a wide field of view, it is often necessary to introduce more optical elements or use specially designed optical components, which not only increases the weight and volume of the optical system but also significantly increases manufacturing costs.

[0003] The Lobster Eye optical system, due to its unique reflective stacking imaging properties, has a broad field of view and a wide applicable spectral range. This feature allows it to be used not only in high-energy radiation fields such as short-wavelength radiation, but also in visible light, infrared, and terahertz bands. In addition, when the ratio of the square cross-section of each small unit that makes up the optical system to its aperture length is kept at a low level, the system can achieve high resolution at the arcsecond level. Each small eye of the Lobster Eye system is arranged along the radius of the sphere, with its axis aligned with the radius of the sphere and pointing to the center of the sphere. This structural feature means that the system has no fixed optical axis, which gives the Lobster Eye optical system its remarkable characteristic of a wide field of view.

[0004] Researching and developing this novel, resolution-selective biomimetic multi-aperture imaging technology can significantly reduce the complexity of optical imaging systems. It is particularly applicable to aerial remote sensing and surveillance, where demanding requirements exist for a large field of view, high resolution, and fast image transmission and processing speeds. This technology not only effectively addresses common challenges in wide-field imaging but also achieves new heights in cost, efficiency, and performance.

[0005] However, it is well known that the field of view and imaging resolution of an optical system are in conflict with each other. Traditional design methods make it difficult to achieve a perfect balance of field of view, imaging resolution, and operating spectrum. This often results in complex system structures, increased weight, and increased costs, hindering practical use of the system. Summary of the Invention

[0006] To solve the above problems, the present invention provides a multi-aperture lobster-eye optical system that can simultaneously locate and image the target, significantly reduces the difficulty of imaging and positioning in the edge field of view, and improves the accuracy and reliability of positioning.

[0007] A multi-aperture lobster-eye optical system comprises a lobster-eye optical subsystem and a central aperture optical subsystem having a common image plane on a central axis. The lobster-eye optical subsystem is a hemispherical structure formed by arranging a plurality of quadrangular pyramidal microchannels, and a through hole is reserved in the middle of the hemispherical structure for mounting the central aperture optical subsystem.

[0008] The cross-section, upper surface and lower surface of the quadrangular pyramid microchannel are all rhombuses with curvature, and the inner wall surfaces of the quadrangular pyramid microchannel are all reflective planes; when the target point light source only enters the field of view of the lobster eye optical subsystem, each quadrangular pyramid microchannel is used to divide the incident light emitted by the target point light source into three paths and reflect it to the image plane, so that three light spot arms intersecting at one point for positioning the target point light source are formed on the image plane; when the target point light source enters the field of view of the lobster eye optical subsystem and the central aperture optical subsystem at the same time, each quadrangular pyramid microchannel is used to divide the incident light emitted by the target point light source into three paths and reflect it to the image plane, and the central aperture optical subsystem is used to image the incident light emitted by the target point light source, so that an image of the target point light source and three light spot arms intersecting at one point for positioning the target point light source are simultaneously formed on the image plane.

[0009] Furthermore, any quadrangular pyramid microchannel reflects the incident light emitted by the target point light source to the image plane along three paths:

[0010] Part of the light is reflected on one set of mutually parallel inner surfaces of the rhombus, and finally converges on the image plane to form the first light spot arm; another part of the light is reflected on another set of mutually parallel inner surfaces of the rhombus, and finally converges on the image plane to form the second light spot arm; the last part of the light is reflected on the four inner surfaces of the rhombus, and the light in the short diagonal direction of the rhombus finally converges on the image plane to form the third light spot arm.

[0011] Furthermore, the target point light source is positioned according to the length change, width change and rotation angle change of the three light spot arms.

[0012] Furthermore, the method for positioning the target point light source through the three light spot arms is:

[0013] When the length of the light spot arm in the lower right corner increases and the width decreases, and the length of the light spot arm in the upper left corner decreases and the width increases, it means that the target point light source moves to the upper left corner;

[0014] When the length of the light spot arm in the lower left corner increases and the width decreases, and the length of the light spot arm in the upper right corner decreases and the width increases, it means that the target point light source moves toward the upper right corner;

[0015] When the length of the light spot arm in the upper right corner increases and the width decreases, and the length of the light spot arm in the lower left corner decreases and the width increases, it means that the target point light source moves to the lower left corner;

[0016] When the length of the light spot arm in the upper left corner increases and the width decreases, and the length of the light spot arm in the lower right corner decreases and the width increases, it means that the target point light source moves to the lower right corner;

[0017] When the length of the light spot arm formed by the light in the short diagonal direction of the rhombus gradually decreases, it means that the target point light source is approaching the multi-aperture lobster-eye optical system;

[0018] When the width of the three light spot arms gradually increases, it means that the target point light source is gradually moving away from the multi-aperture lobster-eye optical system;

[0019] When the angles of the three light spot arms rotate, it means that the target point light source also rotates.

[0020] Furthermore, the lens structure of the central aperture optical subsystem is a five-piece structure, located in the mid-wave infrared band, with a total length of 265mm, a focal length of 200mm, a back focal length of 90mm, a relative aperture of f / 2, and a half field of view angle of 7.5°.

[0021] Furthermore, the total field of view is 40° and the equivalent focal length is 265mm.

[0022] Furthermore, the method for determining the curvature radius R of the hemispherical structure formed by the lobster-eye optical subsystem is as follows:

[0023] Assume that the incident point E of any incident light ray DE from the target point light source D on any pyramid microchannel is the incident point. After multiple reflections in the pyramid microchannel, the exit point F on the pyramid microchannel is the image point A. The center point of the hemispherical surface structure formed by the lobster-eye optical subsystem is O. The foot of the perpendicular to the line segment OD at point F is B. A tangent line is drawn to the outer surface of the lobster-eye optical subsystem at point E. The intersection of this tangent line and the line segment OD is denoted as C.

[0024] Based on the geometric relationship, the curvature radius R of the hemispherical structure formed by the lobster-eye optical subsystem must meet the following constraints on the common image plane between the lobster-eye optical subsystem and the central aperture optical subsystem:

[0025]

[0026] Wherein, L1 is the distance from the first mirror to the last mirror of the central aperture optical subsystem, L2 is the semi-diameter of the central aperture optical subsystem, FB is the perpendicular segment between point F and line segment OD, ∠FOA is the apex angle of the quadrangular pyramid microchannel, ∠FAB is the acute angle between the light emitting direction FA and the central axis OD, and ∠AFO is the angle between the light emitting direction FA and line segment FO;

[0027] Based on the geometric relationship, on the basis of the common image plane of the lobster-eye optical subsystem and the central aperture optical subsystem, the constraint conditions that the ratio of the length to the width λ of any tetrahedral microchannel in the lobster-eye optical subsystem must meet are as follows:

[0028]

[0029] Wherein, γ is the apex angle of the tetrahedral microchannel, and ∠FAO is the obtuse angle between the light emitting direction FA and the central axis OD.

[0030] Beneficial effects:

[0031] 1. The present invention provides a multi-aperture lobster-eye optical system. Compared with traditional lobster-eye optical systems, the new lobster-eye optical system significantly increases the number of spot arms. This improvement significantly reduces the difficulty of imaging positioning in the edge field of view and improves the accuracy and reliability of positioning. In addition, the central aperture optical subsystem is placed in the center to image the target object, which can improve the problem that the lobster-eye optical system itself cannot clearly image the target. Overall, the diamond-shaped lobster-eye lens of the present invention exhibits obvious advantages in both imaging performance and practical applications. It not only significantly reduces the difficulty of imaging positioning in the edge field of view and improves the accuracy and reliability of positioning, but also maintains the original imaging clarity and detail when the angle between the diamond-shaped lobster-eye lens and the detector changes, and the imaging quality is highly stable.

[0032] 2. The present invention provides a multi-aperture lobster-eye optical system, which can effectively acquire and identify the characteristic information of the light source by analyzing the changes in the focal arm in the imaging and the corresponding angle information. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic structural diagram of the multi-aperture lobster eye optical system of the present invention.

[0034] Figure 2 It is a schematic structural diagram of the lobster eye optical subsystem after the hole is dug in the present invention.

[0035] Figure 3 This is a schematic diagram of positioning the light spot in the central field of view of the novel lobster-eye optical system of the present invention.

[0036] Figure 4 It is a schematic diagram of the central aperture optical system structure.

[0037] Figure 5 This is a schematic diagram of imaging a point light source at the edge of the field of view.

[0038] Figure 6 It is a schematic diagram of positioning and imaging a point light source in the field of view.

[0039] Figure 7 This is a schematic diagram of the imaging of a point light source at the center of the field of view by the new lobster-eye optical system.

[0040] Figure 8 This is a schematic diagram of the light propagation model of the new lobster eye optical system. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0042] The present invention aims to resolve the conflict between a large field of view and high resolution in traditional optical systems. Based on the lobster-eye structure, it provides a novel multi-aperture lobster-eye optical system with a unique structure. This system can provide richer image information for any point light source within a large field of view, acquire spectral information of key targets within the field of view, and effectively improve detection accuracy. While maintaining a wide field of view, high-resolution optical components in the central area enable detailed observation of specific areas and identification of long-distance targets. This multi-aperture technology has important application value in optical system design. It not only improves light energy utilization and optimizes imaging quality, but also significantly reduces the weight and complexity of the optical system, and reduces the need for data transmission and processing, thereby reducing costs.

[0043] Specifically, such as Figure 1 As shown, the present invention provides a multi-aperture lobster-eye optical system, comprising a lobster-eye optical subsystem and a central aperture optical subsystem having a common image plane on the central axis, wherein the lobster-eye optical subsystem is a hemispherical structure formed by arranging multiple quadrangular pyramid microchannels, and a through hole is reserved in the middle of the hemispherical structure for mounting the central aperture optical subsystem, as shown in FIG. Figure 2 As shown;

[0044] The cross-section, upper surface and lower surface of the quadrangular pyramid microchannel are all rhombuses with curvature, and the inner wall surfaces of the quadrangular pyramid microchannel are all reflective planes; when the target point light source only enters the field of view of the lobster eye optical subsystem, each quadrangular pyramid microchannel is used to divide the incident light emitted by the target point light source into three paths and reflect it to the image plane, so that three light spot arms intersecting at one point for positioning the target point light source are formed on the image plane; when the target point light source enters the field of view of the lobster eye optical subsystem and the central aperture optical subsystem at the same time, each quadrangular pyramid microchannel is used to divide the incident light emitted by the target point light source into three paths and reflect it to the image plane, and the central aperture optical subsystem is used to image the incident light emitted by the target point light source, so that an image of the target point light source and three light spot arms intersecting at one point for positioning the target point light source are simultaneously formed on the image plane.

[0045] Based on this, the detection process of the present invention can be briefly described as follows: the basic working mode of the system is high-sensitivity detection of a large field of view in the periphery and high-resolution imaging of the central local area. First, when the target enters the field of view, the multi-aperture lobster-eye optical system captures the light radiated by the target, such as Figure 5 As shown. The light is reflected in the microchannel of the spherical shell unit and eventually forms a positioning image on the photodetector. By analyzing the imaging law of the light source on the diamond lobster eye lens, the image signal of the target can be processed to obtain the target's position information. When the field of view angle of the target relative to the multi-aperture lobster eye optical system is less than 15°, as shown in the figure below: Figure 6 When entering the field of view of the central aperture optical system, the target is imaged while being positioned, as shown in Figure 7 As shown, a C-shaped annular light spot can be obtained on the receiving surface.

[0046] It should be noted that the lens structure of the central aperture optical subsystem of the present invention is a five-piece structure located in the mid-wave infrared band, with a total length of 265mm, a focal length of 200mm, a back focal length of 90mm, a relative aperture of f / 2, and a half field of view angle of 7.5°. The specific structure is as follows Figure 4 It should be noted that when optimizing the central aperture optical subsystem using optical design software, custom optimization operands can be added to optimize the aberrations in the optical system. By setting the optimized index values, the optical system can be analyzed and its parameter structure can be changed to gradually approach the set target.

[0047] For the novel lobster-eye optical system, a 60° convex platform base unit structure is first established, and a curved array is performed on the corresponding curve to form the complete novel lobster-eye optical system. Alternatively, a single quadrangular pyramid structure with both upper and lower surfaces in a rhombus shape is first established, and curved arrays are performed on the quadrangular pyramid structure in two directions to ultimately obtain the novel lobster-eye optical system. Both modeling methods accurately reproduce the structure and optical properties of the novel lobster-eye optical system. The total field of view of the multi-aperture lobster-eye optical system is 40°. The total length of the designed central aperture optical system is 265 mm. Due to the unique structural characteristics of the novel lobster-eye optical system, the equivalent focal length of the novel lobster-eye optical system is 265 mm.

[0048] That is to say, the new lobster eye optical system provided by the present invention changes the existing lobster eye microchannel structure, designs the upper and lower surfaces of the quadrangular pyramid microchannel into a rhombus with curvature, and makes a curve array according to the arc of the sphere, and finally obtains a new lobster eye optical system with a rhombus structure. The central aperture optical system is placed in the central area, and high-resolution imaging can be performed while positioning the target. The inner wall surface of the quadrangular pyramid is a plane with reflective properties. When light enters the microchannel, due to the particularity of the quadrangular pyramid microchannel structure, the light will be divided into multiple paths due to the difference in angles. Among them, a part of the light will be reflected on the inner surfaces of the rhombus that are parallel to each other, and finally converge on the image plane. The other part of the light is reflected on the four inner surfaces of the rhombus. Due to the angle of the light in the long diagonal direction, the light will be dispersed, and it is difficult to form a light spot. In the short diagonal direction, the light will not be deflected at too large an angle, and finally converge on the image plane. When it reaches the image plane, three obvious light spot arms will be formed, such as Figure 3 shown.

[0049] Compared to existing technologies, the novel lobster-eye optical system proposed in this invention significantly improves the problem of reduced imaging information in the spot of existing lobster-eye lenses when imaging at the edge of the field of view. Through the optimized design of the lobster-eye lens structure, the system offers numerous advantages: As the field of view angle of the diamond-shaped lobster-eye lens changes, the length and width of the focal arm of the imaging spot, as well as the energy concentration of the central diffuse spot, also change. Furthermore, as the distance between the point light source and the diamond-shaped lobster-eye lens changes, the imaging spot also changes regularly. The numerous advantages of the diamond-shaped lobster-eye lens allow for the simultaneous capture of multi-angle images by analyzing the spot's richer characteristic information to facilitate the determination of the point light source's information. A central aperture optical system is placed at the center of the novel lobster-eye optical system to image objects in the field of view, enabling the multi-aperture lobster-eye optical system to simultaneously perform positioning and imaging functions.

[0050] Furthermore, any quadrangular pyramid microchannel reflects the incident light emitted by the target point light source to the image plane along three paths:

[0051] Part of the light is reflected on one set of mutually parallel inner surfaces of the rhombus, and finally converges on the image plane to form the first light spot arm; another part of the light is reflected on another set of mutually parallel inner surfaces of the rhombus, and finally converges on the image plane to form the second light spot arm; the last part of the light is reflected on the four inner surfaces of the rhombus, and the light in the short diagonal direction of the rhombus finally converges on the image plane to form the third light spot arm.

[0052] It's important to note that the diamond-shaped lobster-eye lens exhibits significantly different imaging effects than traditional lobster-eye lenses at different field-of-view angles and distances. This unique imaging characteristic helps capture and identify the detailed characteristics of a light source through image information. As the light source moves toward the upper left corner, the display of the diamond-shaped lobster-eye imaging system changes. Specifically, the focal arm length in the lower right corner increases while the width decreases, while the focal arm length in the upper left corner decreases while the width increases. This characteristic information about the changes in focal arm length and width can be used to determine the location and related characteristics of the light source. Therefore, by analyzing the changes in the focal arm during imaging and the corresponding angle information, the characteristic information of the light source can be effectively captured and identified.

[0053] Based on this, the present invention locates the target point light source according to the length change, width change and rotation angle change of the three light spot arms, as follows:

[0054] When the length of the light spot arm in the lower right corner increases and the width decreases, and the length of the light spot arm in the upper left corner decreases and the width increases, it means that the target point light source moves to the upper left corner;

[0055] When the length of the light spot arm in the lower left corner increases and the width decreases, and the length of the light spot arm in the upper right corner decreases and the width increases, it means that the target point light source moves toward the upper right corner;

[0056] When the length of the light spot arm in the upper right corner increases and the width decreases, and the length of the light spot arm in the lower left corner decreases and the width increases, it means that the target point light source moves to the lower left corner;

[0057] When the length of the light spot arm in the upper left corner increases and the width decreases, and the length of the light spot arm in the lower right corner decreases and the width increases, it means that the target point light source moves to the lower right corner;

[0058] When the length of the light spot arm formed by the light in the short diagonal direction of the rhombus gradually decreases, it means that the target point light source is approaching the multi-aperture lobster-eye optical system;

[0059] When the width of the three light spot arms gradually increases, it means that the target point light source is gradually moving away from the multi-aperture lobster-eye optical system;

[0060] When the angles of the three light spot arms rotate, it means that the target point light source also rotates.

[0061] That is, when the detector and the multi-aperture lobster-eye optical system are fixed in position, changes in the light source distance affect the image produced by the multi-aperture lobster-eye optical system. Within a certain distance of light source movement, the image maintains a clear spot structure, indicating the presence of optical depth of field. As the distance between the point light source and the multi-aperture lobster-eye optical system decreases, the lengths of the two focal arms corresponding to the shorter diagonal lines of the multi-aperture lobster-eye optical system gradually decrease, eventually disappearing completely. Conversely, as the distance between the light source and the multi-aperture lobster-eye optical system increases, the widths of the three focal arms in the image continue to increase, ultimately causing the light spot to dissipate and the image to lose clarity. When the light source is at infinity, the image's focal spot effect is pronounced, with the two focal arms in the upper right and lower left exhibiting a degree of bifurcation, clearly demonstrating the distribution characteristics of the focal spot.

[0062] When the relative angular position between the multi-aperture lobster-eye optical system and the detector changes, for example by rotating the system through a certain angle, the image formed by the light source passing through the multi-aperture lobster-eye optical system is affected. Specifically, the angle of the imaging spot formed by the point light source during the imaging process of the diamond lobster-eye lens also changes. The angles of the three focal arms of the diamond lobster-eye lens have all rotated. However, despite the change in focal arm angle, the image clarity is not affected, maintaining the original clarity and detail. This demonstrates that the diamond lobster-eye lens has excellent control over the stability of image quality during rotation.

[0063] It should be noted that the advantages of using three light spot arms for positioning in the present invention are reflected in the following aspects:

[0064] 1. Redundancy: The positioning of the intersection of the three spot arms provides redundant information. If the data of one spot arm is erroneous or interfered with, the remaining two spot arms can still provide sufficient information to determine the location of the target. This redundancy improves the reliability of the system.

[0065] 2. Higher precision: Three beam arms can better define a point in space, especially when there are measurement errors. The intersection of two beam arms may be inaccurate due to errors, while the intersection of three beam arms can improve accuracy by solving the optimal value between multiple intersection points.

[0066] 3. Error detection and correction: By comparing the intersection points defined by the three beam arms, outliers or errors can be identified. When the intersection points of the three beam arms are far apart, it can be inferred that there may be a problem with the measurement of a beam arm, which can be corrected in a timely manner.

[0067] 4. Multi-directional positioning: The three beam arms can come from different directions, providing a comprehensive perspective. Compared to two straight beam arms that can only intersect in one plane, the intersection of three beam arms allows positioning to be performed in more complex environments.

[0068] 5. Geometric stability: The intersection of the three light spot arms provides a more stable solution geometrically, especially when dealing with complex terrain or environments, which can effectively reduce the impact of obstacles or interference.

[0069] Furthermore, the present invention combines the designed central aperture optical system with the bionic lobster-eye optical system structure to complete the overall design of the multi-aperture lobster-eye optical system, which requires:

[0070] 1) The lobster-eye optical subsystem and the central aperture optical subsystem perform imaging through the edge channel and the central channel respectively. The light from the two channels forms an image on a common image plane after passing through the sub-optical systems.

[0071] 2) The overall length of the central aperture optical subsystem is designed to not block light, allowing it to converge and form images through the edge channels. Similarly, the microchannels of the lobster eye optical system cannot block light from the central aperture optical system.

[0072] 3) The field of view angles of the central channel and the edge channels should be reasonably distributed during the design process. The aperture of the central aperture optical subsystem should not be too large to prevent interference with the lobster eye microchannel imaging at the boundary line of the field of view.

[0073] The half-field-of-view angle range of the lobster-eye optical subsystem should be larger than that of the central-aperture optical subsystem, and there should be no field-of-view gap between the two optical subsystems. Therefore, a circular through-hole is used to house the central-aperture optical subsystem, which places restrictions on the edge height of the central-aperture optical subsystem. Therefore, the maximum diameter and overall length of the central-aperture optical subsystem at the circular through-hole should be subject to the following constraints:

[0074] like Figure 8 As shown, the microchannel closest to the central aperture optical subsystem is shown. Assume that the incident point E of any incident light ray DE formed by the target point light source D on any pyramid microchannel is the incident point, and the exit point F on the pyramid microchannel after multiple reflections in the pyramid microchannel is the exit point F. The image point of the incident light ray DE on the image plane is A. The center point of the hemispherical surface structure formed by the lobster-eye optical subsystem is O. The foot of the perpendicular to the line segment OD at point F is B. A tangent line is drawn to the outer surface of the lobster-eye optical subsystem at point E, and the intersection of the tangent line and the line segment OD is recorded as C.

[0075] ∠DEC=α1. The angle will change during reflection in the microchannel. According to the geometric relationship, the angle α2 during the second reflection is calculated as:

[0076]

[0077] The exit angle α after n reflections n for:

[0078] α n =α1-(n-1)β

[0079] Where β is the lobster-eye optical system's cone apex angle ∠EOD, and n is the number of reflections within the new lobster-eye optical system's microchannel at the structural boundary. According to the formula, light entering the lobster-eye optical system's microchannel will be unable to pass through the microchannel due to excessive reflections and will instead be emitted in the opposite direction.

[0080] After combining the boundary conditions of the lobster eye light incidence, we can analyze that:

[0081] ∠FAB=90°+(n-1)β+∠FOA-α1

[0082] The lobster-eye optical system and the central optical system have a common image plane on the central axis. Therefore, based on the geometric relationship, the curvature radius R of the hemispherical structure formed by the lobster-eye optical subsystem needs to meet the following constraints on the basis of the common image plane of the lobster-eye optical subsystem and the central aperture optical subsystem:

[0083]

[0084] Wherein, L1 is the distance from the first mirror to the last mirror of the central aperture optical subsystem, L2 is the semi-diameter of the central aperture optical subsystem, FB is the perpendicular segment between point F and line segment OD, ∠FOA is the apex angle of the quadrangular pyramid microchannel, ∠FAB is the acute angle between the light emitting direction FA and the central axis OD, and ∠AFO is the angle between the light emitting direction FA and line segment FO;

[0085] Based on the geometric relationship, on the basis of the common image plane of the lobster-eye optical subsystem and the central aperture optical subsystem, the constraint conditions that the ratio of the length to the width λ of any tetrahedral microchannel in the lobster-eye optical subsystem must meet are as follows:

[0086]

[0087] Wherein, γ is the apex angle of the tetrahedral microchannel, and ∠FAO is the obtuse angle between the light emitting direction FA and the central axis OD.

[0088] Furthermore, the central aperture optical subsystem of the present invention, during the optimization design process using optical design software, incorporates custom optimization operands to optimize the aberrations in the optical system. After setting the optimization index value, the optical system is analyzed and the parameter structure of the optical system is modified to gradually approach the set target. During the optimization process, the field of view angle, aperture size, and overall length assigned to the two different channels are continuously adjusted to balance the impact of the interaction of the multi-aperture optical system on the imaging quality. The specific steps are as follows:

[0089] 1) Set the optical system parameters and boundary conditions of the initial structure, and manually change the initial parameters such as the working spectrum, field of view angle, and entrance pupil diameter of the initial structure.

[0090] 2) The curvature radius, center thickness, and other parameters of the optical glass in the lens of the central aperture optical system are set as variables, and the total length of the optical system is controlled by limiting the optical parameters within special constraints.

[0091] 3) Add boundary conditions for structural parameters such as back focal length restrictions and edge height, and use the global optimization module in code V to further optimize the optical system. From this, you can select the appropriate optical system structure and gradually optimize it until the design requirements are met.

[0092] 4) After optimizing the lens using the virtual refractive index, use the glass fit macro file in the optical design software to select the virtual glass model. If the imaging quality of the optical system degrades after selecting the actual glass model, use the glass expert function to further optimize the design of each glass.

[0093] In summary, the present invention has the following advantages over the prior art:

[0094] 1. The multi-aperture lobster-eye optical system achieves high resolution at the center and large field of view at the edge in a brand-new way. It can not only effectively deal with common problems in wide-field imaging, but also significantly reduce the complexity of the optical imaging system.

[0095] 2. The multi-aperture lobster-eye optical system can simultaneously locate and image the target, significantly reducing the difficulty of imaging and positioning in the edge field of view during positioning, and improving positioning accuracy and reliability. At the same time, the three-arm image of the lobster-eye imaging is highly sensitive, and the position information change of the light source can be reflected in the imaging spot feature information on the detector. When the angle between the diamond-shaped lobster-eye lens and the detector changes, the imaging spot on the detector will also rotate accordingly, while maintaining the original clarity and detail performance, and the imaging quality is highly stable.

[0096] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may of course make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A multi-aperture lobster-eye optical system, characterized in that: The lobster-eye optical subsystem and the central aperture optical subsystem have a common image plane on the central axis, wherein the lobster-eye optical subsystem is a hemispherical structure formed by arranging multiple quadrangular pyramid microchannels, and a through hole is reserved in the middle of the hemispherical structure for installing the central aperture optical subsystem; The cross-section, upper surface and lower surface of the quadrangular pyramid microchannel are all rhombuses with curvature, and the inner wall surfaces of the quadrangular pyramid microchannel are all reflective planes; when the target point light source only enters the field of view of the lobster eye optical subsystem, each quadrangular pyramid microchannel is used to divide the incident light emitted by the target point light source into three paths and reflect it to the image plane, so that three light spot arms intersecting at one point for positioning the target point light source are formed on the image plane; when the target point light source enters the field of view of the lobster eye optical subsystem and the central aperture optical subsystem at the same time, each quadrangular pyramid microchannel is used to divide the incident light emitted by the target point light source into three paths and reflect it to the image plane, and the central aperture optical subsystem is used to image the incident light emitted by the target point light source, so that an image of the target point light source and three light spot arms intersecting at one point for positioning the target point light source are simultaneously formed on the image plane.

2. The multi-aperture lobster-eye optical system according to claim 1, wherein: The three paths along which any quadrangular pyramid microchannel reflects the incident light from the target point light source to the image plane are: Part of the light is reflected on one set of mutually parallel inner surfaces of the rhombus, and finally converges on the image plane to form the first light spot arm; another part of the light is reflected on another set of mutually parallel inner surfaces of the rhombus, and finally converges on the image plane to form the second light spot arm; the last part of the light is reflected on the four inner surfaces of the rhombus, and the light in the short diagonal direction of the rhombus finally converges on the image plane to form the third light spot arm.

3. The multi-aperture lobster-eye optical system according to claim 1, wherein: The target point light source is positioned according to the changes in length, width and rotation angle of the three light spot arms.

4. A multi-aperture lobster-eye optical system according to claim 1 or 3, characterized in that: The method for locating the target point light source through three light spot arms is: When the length of the light spot arm in the lower right corner increases and the width decreases, and the length of the light spot arm in the upper left corner decreases and the width increases, it means that the target point light source moves to the upper left corner; When the length of the light spot arm in the lower left corner increases and the width decreases, and the length of the light spot arm in the upper right corner decreases and the width increases, it means that the target point light source moves toward the upper right corner; When the length of the light spot arm in the upper right corner increases and the width decreases, and the length of the light spot arm in the lower left corner decreases and the width increases, it means that the target point light source moves to the lower left corner; When the length of the light spot arm in the upper left corner increases and the width decreases, and the length of the light spot arm in the lower right corner decreases and the width increases, it means that the target point light source moves to the lower right corner; When the length of the light spot arm formed by the light in the short diagonal direction of the rhombus gradually decreases, it means that the target point light source is approaching the multi-aperture lobster-eye optical system; When the width of the three light spot arms gradually increases, it means that the target point light source is gradually moving away from the multi-aperture lobster-eye optical system; When the angles of the three light spot arms rotate, it means that the target point light source also rotates.

5. The multi-aperture lobster-eye optical system according to claim 1, wherein: The lens structure of the central aperture optical subsystem is a five-piece structure located in the mid-wave infrared band, with a total length of 265mm, a focal length of 200mm, a back focal length of 90mm, a relative aperture of f / 2, and a half field of view angle of 7.5°.

6. The multi-aperture lobster-eye optical system according to claim 1, wherein: The total field of view is 40° and the equivalent focal length is 265mm.

7. The multi-aperture lobster-eye optical system according to claim 1, wherein: The method for determining the curvature radius R of the hemispherical structure formed by the lobster eye optical subsystem is as follows: Assume that the incident point E of any incident light ray DE from the target point light source D on any pyramid microchannel is the incident point. After multiple reflections in the pyramid microchannel, the exit point F on the pyramid microchannel is the image point A. The center point of the hemispherical surface structure formed by the lobster-eye optical subsystem is O. The foot of the perpendicular to the line segment OD at point F is B. A tangent line is drawn to the outer surface of the lobster-eye optical subsystem at point E. The intersection of this tangent line and the line segment OD is denoted as C. Based on the geometric relationship, the curvature radius R of the hemispherical structure formed by the lobster-eye optical subsystem must meet the following constraints on the common image plane between the lobster-eye optical subsystem and the central aperture optical subsystem: Wherein, L1 is the distance from the first mirror to the last mirror of the central aperture optical subsystem, L2 is the semi-diameter of the central aperture optical subsystem, FB is the perpendicular segment between point F and line segment OD, ∠FOA is the apex angle of the quadrangular pyramid microchannel, ∠FAB is the acute angle between the light emitting direction FA and the central axis OD, and ∠AFO is the angle between the light emitting direction FA and line segment FO; Based on the geometric relationship, on the basis of the common image plane of the lobster-eye optical subsystem and the central aperture optical subsystem, the constraint conditions that the ratio of the length to the width λ of any tetrahedral microchannel in the lobster-eye optical subsystem must meet are as follows: Wherein, γ is the apex angle of the tetrahedral microchannel, and ∠FAO is the obtuse angle between the light emitting direction FA and the central axis OD.

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