Optical system for laser communication

Abstract

Provided is an optical system for laser communication. The optical system comprises: a transmissive optical antenna system, the transmissive optical antenna system being located upstream from a dual optical wedge system in a laser optical path of the optical system, and comprises a first objective lens group and a second objective lens group that are each composed of a plurality of lenses. An object plane of the second objective lens group is a focal plane of the first objective lens group, the first objective lens group is configured to focus an incident laser beam to the focal plane of the first objective lens group, and the second objective lens group is configured to reduce laser beams from a same point on the focal plane of the first objective lens group and emit same in parallel. The dual optical wedge system comprises two optical wedges arranged opposite one another, the dual optical wedge system is configured to deflect a parallel laser beam emitted from the transmissive optical antenna system into the field-of-view range of a tracking branch, and the dual-optical wedge system is driven by a driving device. In this way, an optical antenna having a large field-of-view range and a tracking device having a small volume are provided.

Description

Optical systems for laser communication Technical Field

[0001] This invention relates to the field of laser communication, and more particularly to an optical system for laser communication. Background Technology

[0002] In the field of laser communication, such as inter-satellite laser communication, if the field of view (also referred to as "viewing angle" or "field of view angle" in this paper) of the optical antenna is small, the constantly changing trajectory and attitude of the satellite may prevent the communication terminal from capturing the laser signal emitted by the other satellite in a timely manner, thus affecting the establishment of communication. To compensate for the small field of view of the optical antenna, the system often needs to add additional mechanical structures or electronic control devices, such as steering motors and galvanometers, to achieve wide-range scanning of the antenna or multi-directional signal reception.

[0003] However, in laser communication equipment, the presence of steering motors occupies a significant amount of space, increasing the overall size of the communication system and making it difficult to meet the miniaturization and lightweight requirements of modern communication equipment. For example, in some space laser communication applications, space is limited on satellites or spacecraft; excessively large motors restrict the installation and layout of the communication system, affecting the integration and use of other equipment. Furthermore, if the galvanometer used for rapidly changing the laser beam direction is too large, it reduces the integration of the optical system, making it difficult to tightly integrate with other optical components. This not only increases the system's size but also affects the stability and accuracy of the optical path. For instance, in some laser communication systems requiring high-precision beam pointing control, an excessively large galvanometer may lead to decreased optical path adjustment accuracy, affecting communication quality and reliability. These additional devices and structures increase the system's weight, size, and energy consumption, not only increasing system complexity but also raising costs and maintenance difficulties.

[0004] To overcome the aforementioned problems, there are two main types of optical systems for laser communication in the existing technology. The first type is equipped with an optical antenna based on a Galilean transmission configuration; the second type is an optical system for laser communication equipped with an off-axis optical antenna.

[0005] For the first type of laser communication optical system, its optical antenna has a small field of view. For example, a typical four-element spherical antenna can only achieve a range of <1°. Therefore, the directional scanning range when used in an optomechanical system is small, requiring the use of a galvanometer and a steering motor. In addition, the Galilean configuration has no focal point at the center, and the beam is not significantly contracted, requiring a large aperture for the folding mirror.

[0006] For the second type of laser communication optical system, its optical antenna has a small field of view. Generally, the field of view of an off-axis dual-mirror system can only reach <0.5°. Therefore, when used in an optomechanical system, the directional scanning range is small, requiring the use of a galvanometer and a steering motor. In addition, the off-axis dual-mirror configuration and the use of aspherical primary and secondary mirrors require high processing precision, resulting in high costs and high assembly and adjustment difficulties.

[0007] In summary, the shortcomings of traditional methods for reducing the size of optical communication systems are: the field of view of optical antennas is relatively small, and additional components such as steering motors and galvanometers are required to achieve antenna scanning or multi-directional signal reception, resulting in high costs. Summary of the Invention

[0008] This invention provides an optical system for laser communication that can significantly improve the field of view of the optical antenna and reduce the size of the tracking device.

[0009] According to one aspect of this disclosure, an optical system for laser communication is provided. The optical system includes: a transmissive optical antenna system located upstream of a dual-wedge system in the laser optical path of the optical system, and comprising a first objective lens group and a second reflecting objective lens group, each composed of multiple lenses, wherein the object plane of the second reflecting objective lens group is the focal plane of the first objective lens group, the first objective lens group is configured to focus an incident laser beam onto the focal plane of the first objective lens group, and the second reflecting objective lens group is configured to converge and parallelize a laser beam from the same point at the focal plane of the first objective lens group; and a dual-wedge system comprising two opposing optical wedges, the dual-wedge system being configured to deflect a parallel laser beam emitted from the transmissive optical antenna system into the field of view of the tracking branch, and the dual-wedge system being driven by a driving device.

[0010] In some embodiments, the transmissive optical antenna system further includes a deflector mirror located at the focal plane of the first objective lens group, the deflector mirror being configured to reflect a laser beam emitted from the first objective lens group toward the second reflector lens group.

[0011] In some embodiments, the ratio of the focal length to the aperture of the first objective lens group is between 3 and 3.5, the length of the first objective lens group is less than or equal to 2 / 3 of the length of the transmission optical antenna system, and the wavefront aberration of the first objective lens group is less than 1 / 12 of the wavelength of the laser beam.

[0012] In some embodiments, the product of the focal length of the second mirror group and the magnification of the transmission optical antenna system is equal to the focal length of the first mirror group, the length of the second mirror group is less than or equal to 1 / 3 of the length of the transmission optical antenna system, the image space of the second mirror group is unfocused, and the wavefront aberration of the second mirror group is less than 1 / 12 of the wavelength of the laser beam.

[0013] In some embodiments, the first objective lens group includes a convex plano lens, a first meniscus lens, a biconcave negative lens, and a second meniscus lens arranged sequentially along the laser optical path.

[0014] In some embodiments, the convex plano lens and the first meniscus lens are made of crown glass, and the biconcave negative lens and the second meniscus lens are made of flint glass.

[0015] In some embodiments, the second mirror group includes a plano-convex positive lens, a convex plano-positive lens, a meniscus positive lens, and a meniscus negative lens arranged sequentially along the laser optical path, wherein the dispersion capability of the plano-convex positive lens, the convex plano-positive lens, and the meniscus positive lens is higher than that of the meniscus negative lens.

[0016] In some embodiments, the driving device is configured to drive the two optical wedges in the dual optical wedge system to rotate around the main optical axis in the same direction and angular velocity.

[0017] In some embodiments, the driving device includes a driver for a dual optical wedge system, the driver being configured to generate the relative placement angle and co-rotational angular velocity of the two optical wedges corresponding to any viewing angle within the viewing angle range of the first objective lens group.

[0018] In some embodiments, the drive device is configured to repeat the following drive until scanning of any angle within the field of view of the first objective lens group is completed: the drive device positions the two optical wedges at a relative placement angle corresponding to the arbitrary angle, and drives the two optical wedges to rotate 360 ​​degrees around the principal optical axis at the same rotational angular velocity.

[0019] In some embodiments, the side of each of the two optical wedges is covered by a mirror mount, the side being adjacent to the chamfer and circular surface of the optical wedge, the outer surface of the mirror mount being gear-shaped, and the driving device including two drive motors, each of the two drive motors driving a gear, the gears and the mirror mount forming a transmission through a track.

[0020] It should be understood that the beneficial effects of the present invention are as follows: By focusing the incident laser beam to the focal plane of the first objective lens group at least via the transmissive optical antenna system, the present invention can increase the field of view; in addition, by deflecting the parallel laser beam emitted from the transmissive optical antenna system into the field of view of the tracking branch using the dual optical wedge system and driving the optical wedge to move, the present invention can achieve a circular change of the optical axis for scanning the laser signal, replacing the tracking fast-reflecting mirror which has a smaller scanning field of view and higher cost. Furthermore, by adopting an optical antenna configuration similar to a Keplerian telescope system, consisting of a first objective lens group, a planar mirror, and a second reflecting objective lens group, the field of view is further increased and the system size is reduced.

[0021] It should be understood that the description in the Summary of the Invention section is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0022] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0023] Figure 1 shows a schematic diagram of an optical system for laser communication according to some embodiments of the present invention;

[0024] Figure 2 shows a schematic diagram of the arrangement and optical path of the first objective lens group according to some embodiments of the present invention;

[0025] Figure 3 shows a schematic diagram of the arrangement and optical path of the second reflective lens group according to some embodiments of the present invention;

[0026] Figure 4 shows a schematic diagram of the combined arrangement and optical path of the first objective lens group and the second reflection objective lens group according to some embodiments of the present invention;

[0027] Figure 5 illustrates the arrangement of the optical system at different field-of-view angles according to some embodiments of the present invention; and

[0028] Figure 6 shows a schematic diagram of a transmission device for rotating a light wedge according to some embodiments of the present invention.

[0029] In all the accompanying figures, the same or similar reference numerals denote the same or similar elements. Detailed Implementation

[0030] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0031] In the description of embodiments of this disclosure, the term "comprising" and similar terms should be understood as open-ended inclusion, i.e., "including but not limited to". The term "based on" should be understood as "at least partially based on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0032] Figure 1 shows a schematic diagram of an optical system 100 for laser communication according to some embodiments of the present invention. As shown in Figure 1, the optical system includes a transmissive optical antenna system and a dual optical wedge system, wherein the transmissive optical antenna system is located upstream of the dual optical wedge system in the laser optical path of the optical system 100, and includes a first objective lens group 102, a turning mirror 104, and a second reflecting objective lens group 106.

[0033] In some embodiments, the first objective lens group 102 includes a plurality of lenses located upstream of the concave-convex mirror 104 in the laser optical path and configured to focus an incident laser beam onto the focal plane of the first objective lens group 102, wherein the material and shape of the plurality of lenses are selected by the final result of an optimization design process. The second reflecting objective lens group 106 is located downstream of the concave-convex mirror 104 in the laser optical path, its object plane being the focal plane of the first objective lens group 102, and is composed of a plurality of lenses (determined by the final result of an optimization design process), and is configured to constrict the laser beam incident from the first objective lens group 102.

[0034] In some embodiments, the deflector mirror 104 is located at the focal plane of the first objective lens group 102 and is configured to reflect the laser beam emitted from the first objective lens group 102 toward the second reflecting objective lens group 106. In some embodiments, the placement angle of the deflector mirror 104 is generally 45°, but it can also be placed at any other arbitrary angle depending on overall requirements. Since the deflector mirror 104 is located at the focal plane of the first objective lens group 102, the beam width is small, so only the focal plane size introduced by the field of view and the width of the defocusing portion of the edge field of view need to be considered, and the required aperture of the deflector mirror 104 is small.

[0035] With a configuration similar to a Keplerian telescope system consisting of a first objective lens group 102, a folding mirror 104, and a second reflecting objective lens group 106, the field of view of the first objective lens group can reach 10 degrees, which is at least 10 times higher than that of traditional technology. By placing the folding mirror 104 at the central focal plane, the aperture of the folding mirror 104 is effectively reduced.

[0036] In some embodiments, the dual-wedge system includes two opposing first wedges 108-1 and second wedges 108-2. The dual-wedge system is configured to deflect a parallel laser beam emitted from the same focal point at the focal plane of the transmissive optical antenna system into the field of view of the tracking branch (e.g., perpendicular to the target surface of the camera). The dual-wedge system is driven by a first drive unit 110-1 and a second drive unit 110-2 via a pivot 112. Because the field of view of the tracking branch is much smaller than that of the transmissive optical antenna system, a scanning device is needed to maximize the incidence of the laser beam emitted from the transmissive optical antenna system into the tracking branch field of view. However, by using a dual-wedge system as the scanning device, no additional steering motor and galvanometer are required. Compared to tracking mirrors with smaller field of view and higher costs, the dual-wedge system of this invention has significant advantages in terms of scanning range, response speed, manufacturing cost, and system integration.

[0037] In some embodiments, the optical wedge can be made of a transmissive material with a certain refractive index. A large-angle antireflective coating is deposited on both planes of the wedge, forming an included angle between them, typically 10-30° depending on the application requirements. The parallel laser beam is deflected by a certain angle after passing through the optical wedge; this deflection angle is determined by the refractive index of the wedge material and the wedge angle. Generally, one optical wedge can achieve a deflection of 5-15°. If the refractive index is 2, then a wedge with a 15° wedge angle can achieve a 15° deflection. Data shows that for an optical system for laser communication equipped with two optical wedges, a deflection of 30° can be achieved.

[0038] Figure 2 shows a schematic diagram of the arrangement and optical path of a first objective lens group 102 according to some embodiments of the present invention. As shown in Figure 2, the first objective lens group 102 includes a first lens 202, a second lens 204, a third lens 206, and a fourth lens 208 placed sequentially along the laser optical path. Light rays passing through each lens of the first objective lens group 102 are focused at the focal plane of the first objective lens group 102. As described above, the material and shape selection of the first lens 202, the second lens 204, the third lens 206, and the fourth lens 208 are determined by the final result of an optimization design process.

[0039] In some embodiments, the process of optimizing the design of the materials and shapes of the individual lenses in the first objective lens group 102 includes the following steps.

[0040] (1) Based on the requirements for the aperture, field of view and total length of the transmission optical antenna system, select a suitable initial configuration for the first objective lens group 102 and determine the initial total length and focal length. For example, since the requirements for the field of view and aperture are relatively large, and the total length of the system is limited and the wavelength range used is small, the initial configuration may be selected, for example, but not limited to, the Ernostar telephoto objective lens, which is a relatively classic initial configuration that meets the requirements of a large aperture and a large field of view.

[0041] (2) Set the ratio of focal length to aperture of the first objective lens group 102, the ratio of length of the first objective lens group 102 to length of the transmission optical antenna system, wavefront aberration, etc., to set the full field-of-view evaluation function. For example, set the ratio of focal length to aperture of the first objective lens group 102 to between 3 and 3.5, set the length of the first objective lens group 102 to be less than or equal to 2 / 3 of the length of the transmission optical antenna system, and set the wavefront aberration of the first objective lens group 102 to be less than 1 / 12 of the wavelength of the laser beam.

[0042] (3) Set the radius of curvature, thickness and material of each lens in the first objective lens group 102 as variables and add corresponding constraints.

[0043] (4) Optimize the first objective lens group 102 until its performance is close to the requirements to obtain the first objective lens group.

[0044] In some embodiments, the first lens 202 is a convex plano-positive lens, the second lens 204 is a meniscus-positive lens, the third lens 206 is a biconcave negative lens, and the fourth lens 208 is a meniscus-positive lens. The first lens 202 and the second lens 204 are low-refractive, high-dispersion crown glass, and the third lens 206 and the fourth lens 208 are high-refractive, low-dispersion flint glass. The optical parameters of the first objective lens group 102, composed of these lenses, are, for example, an aperture of 60 mm, an F-number of 3-3.5, a focal length of 180 mm, a field of view of ±5 degrees, and a total length of 120 mm. The first objective lens group 102 optimizes spherical aberration, primary coma, and astigmatism, for example, through material matching and positive / negative meniscus symmetry and a biconcave configuration. A small amount of advanced coma, astigmatism, and field curvature remain to be compensated.

[0045] Figure 3 shows a schematic diagram of the arrangement and optical path of the second reflecting lens group 106 according to some embodiments of the present invention. As shown in Figure 3, the second reflecting lens group 106 includes a fifth lens 302, a sixth lens 304, a seventh lens 306, and an eighth lens 308 placed sequentially along the laser optical path. The second reflecting lens group 106 uses the focal plane of the first reflecting lens group 102 as its object plane and is conjugate to the image plane at infinity. As described above, the material and shape selection of the fifth lens 302, sixth lens 304, seventh lens 306, and eighth lens 308 placed sequentially along the laser optical path in the second reflecting lens group 106 are determined by the final result of the optimization design process.

[0046] In some embodiments, the process of optimizing the design of the materials and shapes of the individual lenses in the second mirror group 106 includes the following steps.

[0047] (1) Based on the magnification and total length requirements of the transmission optical antenna system, select a suitable initial configuration for the second mirror group 106, and determine the initial focal length and system aperture of the second mirror group 106. For example, based on the magnification requirements of the transmission optical antenna system, the focal length of the second mirror group 106 is relatively small, which is the focal length of the first mirror group 102 divided by the magnification. Considering the relatively large aperture and the large image-side field of view after beam contraction, for example, but not limited to, a Zeiss eyepiece is selected as the initial configuration, and the doublet is split into two independent pieces.

[0048] (2) Keep the first objective lens group 102 unchanged, and connect the second mirror objective lens group 106 behind the focal plane of the first objective lens group 102 according to the initial object distance of the Zeiss eyepiece.

[0049] (3) Set the ratio of the length of the second mirror group 106 to the length of the transmission optical antenna system, wavefront aberration, etc., to set the full field-of-view evaluation function. For example, set the length of the second mirror group 106 to be less than or equal to 1 / 3 of the length of the transmission optical antenna system, and set the wavefront aberration of the second mirror group 106 to be less than 1 / 12 of the wavelength of the laser beam.

[0050] (4) Set the radius of curvature, thickness and material of each lens in the second mirror group 106 as variables and add corresponding constraints.

[0051] (5) Optimize each lens to bring its performance close to the requirements to obtain the second mirror group 106.

[0052] In some embodiments, the fifth lens 302 is a plano-convex positive lens, the sixth lens 304 is a convex plano-positive lens, the seventh lens 306 is a meniscus positive lens, and the eighth lens 308 is a meniscus negative lens. The fifth lens 302, sixth lens 304, and seventh lens 306 are made of a high-dispersion material, while the eighth lens is made of a low-dispersion material. The optical parameters of the second reflecting objective lens group 106, composed of these lenses, are, for example, a focal length of 30 mm and a field of view of ±30 degrees. The second reflecting objective lens group 106 compensates for the residual aberrations of the first objective lens group 102 through its symmetrical configuration and the meniscus lens.

[0053] Figure 4 illustrates a schematic diagram of a combined arrangement 400 of a first objective lens group 102 and a second reflecting objective lens group 106 according to some embodiments of the present invention, and the optical path. As shown in Figure 4, the combined arrangement 400 includes a first objective lens group 102 upstream of the laser optical path and a second reflecting objective lens group 106 downstream of the laser optical path. The first objective lens group 102 is, for example, a telephoto objective lens configuration, and the second reflecting objective lens group 106 is, for example, a Zeiss eyepiece configuration. The combined arrangement 400 is obtained through an overall optimization process of the first objective lens group 102 and the second reflecting objective lens group 106.

[0054] In some embodiments, the overall optimization process for the combined arrangement 400 includes: further optimizing the overall image quality (equivalent to "wavelength aberration") while keeping the aperture, field of view, total length requirements and magnification of the transmissive optical antenna system unchanged, and paying attention to the cost of device materials, tolerance sensitivity and image quality degradation caused by temperature changes, so as to finally obtain a complete transmissive optical antenna system.

[0055] By employing a combination of telephoto objectives and Zeiss eyepieces for optimization, the system can maintain good image quality within a 10° field of view without requiring a large-angle motor bandpass optical system for coarse tracking alignment, thus saving space.

[0056] Figure 5 illustrates the arrangement of the optical system at different field-of-view angles according to some embodiments of the present invention. As shown in Figure 5, the first optical wedge 108-1 and the second optical wedge 108-2 in the dual optical wedge system are placed at different relative angles in portions (a) to (c) shown in Figure 5. Portion (a) in Figure 5 corresponds to a 0-degree field of view, portion (b) in Figure 5 corresponds to a -3-degree field of view, and portion (c) in Figure 5 corresponds to a 5-degree field of view. Correspondingly, the deflection angle of the principal optical axis relative to the vertical axis is also different. When the first optical wedge 108-1 and the second optical wedge 108-2 are placed at a certain relative angle and rotate about the axis in the same direction and at the same angular velocity, the normal of the inclined surface of the optical wedge also rotates about the principal optical axis, so the scanning area is a circle.

[0057] In some embodiments, a first driving device 110-1 and a second driving device 110-2, which are respectively connected to the first optical wedge 108-1 and the second optical wedge 108-2 via a pivot 112, drive the first optical wedge 108-1 and the second optical wedge 108-2 to rotate around the main optical axis in the same direction and at the same angular velocity. For example, the first driving device 110-1 and the second driving device 110-2 are drive motors.

[0058] In some embodiments, the driving device includes a driver for a dual-wedge system, the driver being configured to generate the relative placement angle and co-rotational angular velocity of the two optical wedges 108-1 and 108-2 corresponding to any viewing angle within the viewing angle range of the first objective lens group 102. For example, the -5-5° field of view is combined with the tracking branch field of view, discretized into a certain number of equal parts, and the relative angle corresponding to each field of view is calculated.

[0059] In some embodiments, the driving device is configured to repeat the following drive until scanning of any viewing angle within the field of view of the first objective lens group 102 is completed: the driving device positions the two optical wedges 108-1 and 108-2 at a relative placement angle corresponding to the arbitrary viewing angle, and drives the two optical wedges 108-1 and 108-2 to rotate 360 ​​degrees around the principal optical axis at the same rotational angular velocity. In this way, scanning of the entire field of view of the optical system 100 can be achieved.

[0060] In some embodiments, when the dual-wedge system scans the spot into the field of view of the tracking branch, it enters the fine tracking mode and adjusts the relative placement angle to bring the spot into the center of the field of view (e.g., the center of the camera) to maintain the fine tracking state.

[0061] Figure 6 shows a schematic diagram of a transmission device 600 for rotating a light wedge according to some embodiments of the present invention. Taking the transmission device 600 for a first light wedge 108-1 as an example, as shown in Figure 6, the transmission device 600 includes a gear 606, a track 610, and a mirror base 608. The mirror base 608 covers the side surface of the first light wedge 108-1, which is adjacent to the chamfered surface and circular surface of the first light wedge 108-1. The outer surface of the mirror base 608 is machined into a gear shape. The gear 606 is driven by a drive motor 602 via a drive shaft 604, and drives the rotation of the mirror base 608 via the track 610.

[0062] By studying the accompanying drawings, the disclosure, and the appended claims, those skilled in the art can understand and implement other variations of the disclosed embodiments when carrying out the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude multiple. The mere fact that certain measures are recited in mutually different dependent claims does not imply that combinations of these measures cannot be fully utilized. Any reference signs in the claims should not be construed as limiting the scope.

[0063] The term "comprising" also includes embodiments that "comprise" or "formulate".

[0064] The present invention is also applicable to devices, apparatuses, or systems that include one or more of the characterizing features described in the specification and / or shown in the drawings. The present invention also relates to methods or processes that include one or more of the characterizing features described in the specification and / or shown in the drawings. Furthermore, if an embodiment of a method or approach performed in a device, apparatus, or system is described, it should be understood that the device, apparatus, or system is suited to or configured for (performing) a method or an embodiment of that method.

[0065] The various aspects discussed in this patent can be combined to provide additional advantages. Furthermore, those skilled in the art will understand that embodiments can be combined, and more than one embodiment can be combined. Additionally, some features can form the basis of one or more divisional applications.

Claims

1. An optical system for laser communication, characterized in that, include: A transmissive optical antenna system is located upstream of a dual-wedge system in the laser optical path of an optical system, and includes a first objective lens group and a second reflective objective lens group, each composed of multiple lenses. The object plane of the second reflective objective lens group is the focal plane of the first objective lens group. The first objective lens group is configured to focus an incident laser beam onto the focal plane of the first objective lens group through each lens of the first objective lens group. The second reflective objective lens group is configured to reduce the laser beam from the same point on the focal plane of the first objective lens group and emit it in parallel. A dual-wedge system includes two opposing optical wedges, the dual-wedge system being configured to deflect a parallel laser beam emitted from the transmissive optical antenna system into the field of view of the capture branch, and the dual-wedge system being driven by a driving device; as well as The driving device includes a driver for the dual optical wedge system, which is configured to generate the relative placement angle and co-rotational angular velocity of the two optical wedges corresponding to any viewing angle within the viewing angle range of the first objective lens group.

2. The optical system according to claim 1, characterized in that, The transmissive optical antenna system also includes: A folding mirror, located at the focal plane of the first objective lens group, is configured to reflect a laser beam emitted from the first objective lens group toward the second mirror lens group.

3. The optical system according to claim 2, characterized in that, The ratio of the focal length to the aperture of the first objective lens group is between 3 and 3.5, the length of the first objective lens group is less than or equal to 2 / 3 of the length of the transmission optical antenna system, and the wavefront aberration of the first objective lens group is less than 1 / 12 of the wavelength of the laser beam.

4. The optical system according to claim 3, characterized in that, The product of the focal length of the second reflective lens group and the magnification of the transmission optical antenna system is equal to the focal length of the first reflective lens group. The length of the second reflective lens group is less than or equal to 1 / 3 of the length of the transmission optical antenna system. The image space of the second reflective lens group is unfocused and the wavefront aberration of the second reflective lens group is less than 1 / 12 of the wavelength of the laser beam.

5. The optical system according to claim 3, characterized in that, The first objective lens group includes a convex plano lens, a first meniscus lens, a biconcave negative lens, and a second meniscus lens, which are placed sequentially along the laser optical path.

6. The optical system according to claim 5, characterized in that, The convex plano lens and the first meniscus lens are made of crown glass, while the biconcave negative lens and the second meniscus lens are made of flint glass.

7. The optical system according to claim 4, characterized in that, The second mirror assembly includes a plano-convex positive lens, a convex plano-positive lens, a meniscus positive lens, and a meniscus negative lens arranged sequentially along the laser optical path, wherein the dispersion capability of the plano-convex positive lens, the convex plano-positive lens, and the meniscus positive lens is higher than that of the meniscus negative lens.

8. The optical system according to claim 1, characterized in that, The driving device is configured to drive the two optical wedges in the dual optical wedge system to rotate around the main optical axis in the same direction and angular velocity.

9. The optical system according to claim 8, characterized in that, The drive mechanism is configured to repeat the following drive until scanning of any angle within the field of view of the first objective lens group is completed: The driving device positions the two optical wedges at the relative placement angle corresponding to the arbitrary viewpoint, and drives the two optical wedges to rotate 360 ​​degrees around the main optical axis at the same rotational angular velocity.

10. The optical system according to claim 9, characterized in that, The side of each of the two optical wedges is covered by a mirror base. The side is adjacent to the chamfer and circular surface of the optical wedge. The outer surface of the mirror base is gear-shaped. The driving device includes two drive motors, each of which drives a gear. The gears and the mirror base are connected by a track.

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