Optical systems for laser communications

Abstract

An optical system for laser communication is provided. The optical system includes a transmission optical antenna system, which is located upstream of a double optical wedge system in the laser optical path of the optical system, and includes a first objective lens group and a second anti-objective lens group respectively composed of a plurality of lenses, the object plane of the second anti-objective lens group is the focal plane of the first objective lens group, the first objective lens group is configured to focus the incident laser beam to the focal plane of the first objective lens group, and the second anti-objective lens group is configured to shrink the laser beam from the same point at the focal plane of the first objective lens group and then emit it in parallel; a double optical wedge system includes two oppositely arranged optical wedges, the double optical wedge system is configured to deflect the parallel laser beam emitted from the transmission optical antenna system into the field of view of the tracking branch, and the double optical wedge system is driven by a driving device. In this way, an optical antenna with a larger field of view angle range and a tracking device with a smaller volume are provided.

Description

Technical Field

[0001] The invention relates to the field of laser communication, and in particular to an optical system used for laser communication. Background Art

[0002] In the field of laser communication, for example, in inter-satellite laser communication, if the field of view of the optical antenna (also referred to as "viewing angle" or "field of view angle" in this article) is small, the satellite's trajectory and attitude are constantly changing, which may cause the communication terminal to be unable to capture the laser signal sent by the other satellite in time, affecting the establishment of communication. In order 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 large-range scanning of the antenna or multi-directional signal reception.

[0003] However, in laser communication equipment, the presence of the steering motor will take up a lot of space, which will increase the volume of the entire communication system and make it difficult to meet the requirements of modern communication equipment for miniaturization and lightweight. For example, in some space laser communication applications, the space on satellites or aircraft is limited, and the excessive size of the motor will limit the installation and layout of the communication system and affect the installation and use of other equipment. In addition, if the galvanometer used to quickly change the direction of the laser beam is too large, the integration of the optical system will be reduced, and it will be difficult to integrate it tightly with other optical components. This will not only increase the volume of the system, but also affect the stability and accuracy of the optical path. For example, in some laser communication systems that require high-precision beam pointing control, the excessive size of the galvanometer may cause the adjustment accuracy of the optical path to decrease, affecting the quality and reliability of communication. These additional equipment and structures will increase the weight, volume and energy consumption of the system, which will not only increase the complexity of the system, but also increase the cost and maintenance difficulty of the system.

[0004] In order to overcome the above problems, there are two mainstream optical systems for laser communication in the prior art: the first is an optical system for laser communication configured with an optical antenna based on a Galilean transmission configuration; the second is an optical system for laser communication configured with an off-axis optical antenna.

[0005] For the first type of laser communication optical system, the field of view of the optical antenna is small. For example, a general four-piece spherical antenna can only reach a range of <1°. Therefore, the directional scanning range when used in the optical machine system is small, and it needs to be used with a galvanometer and a steering motor. In addition, the center of the Galilean configuration is non-focused, the beam is not significantly narrowed, and the turning mirror requires a larger aperture.

[0006] For the second type of laser communication optical system, the optical antenna field of view is small, and the field of view of the off-axis double-reflector can generally only reach a range of <0.5°. Therefore, when the optical machine system is used, the directional scanning range is small, and it needs to be used with a galvanometer and a steering motor. In addition, the off-axis double-reflector configuration and the use of aspherical primary and secondary mirrors require high processing accuracy, high cost, and high difficulty in assembly and adjustment.

[0007] In summary, the shortcomings of the traditional method for reducing the volume of optical communication systems are: the field of view angle of the optical antenna is relatively small, and additional devices such as steering motors and galvanometers are required to achieve antenna scanning or multi-directional signal reception, which is costly. Summary of the invention

[0008] The present invention provides an optical system for laser communication, which can significantly improve the viewing angle range of an optical antenna and reduce the volume of a tracking device.

[0009] According to one aspect of the present disclosure, an optical system for laser communication is provided. The optical system includes: a transmission optical antenna system, which is located upstream of a double optical wedge system in the laser optical path of the optical system, and includes a first objective lens group and a second anti-objective lens group respectively composed of a plurality of lenses, the object plane of the second anti-objective lens group is the focal plane of the first objective lens group, the first objective lens group is configured to focus the incident laser beam to the focal plane of the first objective lens group, and the second anti-objective lens group is configured to shrink the laser beam from the same point at the focal plane of the first objective lens group and then emit it in parallel; and a double optical wedge system, including two oppositely arranged optical wedges, the double optical wedge system is configured to deflect the parallel laser beam emitted from the transmission optical antenna system into the field of view of the tracking branch, and the double optical wedge system is driven by a driving device.

[0010] In some embodiments, the transmission optical antenna system further includes: a turning mirror located at a focal plane of the first objective lens group, wherein the turning mirror is configured to reflect the laser beam emitted from the first objective lens group toward the second anti-objective 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 transmissive optical antenna system, and the wave 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 anti-objective lens group and the magnification of the transmission optical antenna system is equal to the focal length of the first objective lens group, the length of the second anti-objective lens group is less than or equal to 1 / 3 of the length of the transmission optical antenna system, the second anti-objective lens group is afocal in image space and the wave aberration of the second anti-objective lens 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 flat positive lens, a first meniscus positive lens, a double concave negative lens, and a second meniscus positive lens placed in sequence along the laser light path.

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

[0015] In some embodiments, the second anti-objective lens group includes a plano-convex positive lens, a convex-planar positive lens, a meniscus positive lens and a meniscus negative lens placed in sequence along the laser light path, wherein the dispersion capabilities of the plano-convex positive lens, the convex-planar positive lens and the meniscus positive lens are all higher than the dispersion capability of the meniscus negative lens.

[0016] In some embodiments, the driving device is configured to drive the two optical wedges in the double 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 the double wedge system, and the driver is configured to generate a relative placement angle and a co-directional rotation angular velocity of the two wedges corresponding to any viewing angle within the viewing angle range of the first objective lens group.

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

[0019] In some embodiments, a side surface of each of the two optical wedges is covered by a mirror mount, the side surface is adjacent to the chamfered surface and the circular surface of the optical wedge, the outer surface of the mirror mount is gear-shaped, and the driving device includes two driving motors, each of which drives a gear, and the gear and the mirror mount form a transmission through a track.

[0020] It should be understood that the beneficial effects of the present invention are: by making the transmission optical antenna system focus the incident laser beam to the focal plane of the first objective lens group at least through the first objective lens group, the present invention can increase the field of view angle; in addition, by making the double wedge system deflect the parallel laser beam emitted from the transmission optical antenna system to the field of view of the tracking branch, and driving the wedge to move, the present invention can realize the annular change of the optical axis for scanning the laser signal, replacing the tracking and aiming fast reflection mirror with a small scanning field of view angle and high cost. Furthermore, by adopting the configuration of the optical antenna composed of the first objective lens group, the flat reflection mirror and the second reflection objective lens group, which is similar to the Kepler telescope system, the field of view angle is further increased and the system volume is reduced.

[0021] It should be understood that the contents described in the Summary of the Invention are not intended to limit the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements.

[0023] Figure 1 A schematic diagram of an optical system for laser communication according to some embodiments of the present invention is shown.

[0024] Figure 2 A schematic diagram showing the arrangement and optical path of a first objective lens group according to some embodiments of the present invention is shown.

[0025] Figure 3 A schematic diagram showing the arrangement of a second anti-objective lens group and an optical path according to some embodiments of the present invention is shown.

[0026] Figure 4 A schematic diagram showing the combined arrangement and optical path of a first objective lens group and a second anti-objective lens group according to some embodiments of the present invention is shown.

[0027] Figure 5 The arrangement of the optical system at different field angles according to some embodiments of the present invention is shown.

[0028] Figure 6 A schematic diagram of a transmission device for rotating an optical wedge according to some embodiments of the present invention is shown.

[0029] Throughout the drawings, the same or similar reference numbers denote the same or similar elements. DETAILED DESCRIPTION

[0030] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are only for exemplary purposes and are not intended to limit the scope of protection of the present disclosure.

[0031] In the description of the embodiments of the present disclosure, the term "including" and similar terms should be understood as open inclusion, that is, "including but not limited to". The term "based on" should be understood as "based at least in part 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 FIG. 1 is a schematic diagram of an optical system 100 for laser communication according to some embodiments of the present invention. Figure 1 As shown, the optical system includes a transmissive optical antenna system and a double wedge system, wherein the transmissive optical antenna system is located upstream of the double wedge system in the laser light path of the optical system 100, and includes a first objective lens group 102, a turning mirror 104 and a second anti-objective lens group 106.

[0033] In some embodiments, the first objective lens group 102 includes a plurality of lenses, which are located upstream of the turning mirror 104 in the laser light path, and are configured to focus the incident laser beam to the focal plane of the first objective lens group 102, wherein the material and shape selection of the plurality of lenses are determined by the final result of the optimization design process. The second anti-objective lens group 106 is located downstream of the turning mirror 104 in the laser light path, and its object plane is the focal plane of the first objective lens group 102, and is composed of a plurality of lenses (determined by the final result of the optimization design process), and the second anti-objective lens group 106 is configured to narrow the laser beam incident from the first objective lens group 102.

[0034] In some embodiments, the turning 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 defocusing lens group 106. In some embodiments, the placement angle of the turning mirror 104 is generally 45°, and it can also be placed at any other angle according to overall requirements. Since the turning mirror 104 is located at the focal plane position 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 edge field of view defocusing turning part need to be considered, and the required aperture of the turning mirror 104 is small.

[0035] Through the configuration similar to the Keplerian telescope system consisting of the first objective lens group 102, the turning flat mirror 104 and the second anti-objective lens group 106, the viewing angle range 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 turning flat mirror 104 at the central focal plane position, the aperture of the turning flat mirror 104 is effectively reduced.

[0036] In some embodiments, the dual optical wedge system includes two first optical wedges 108-1 and second optical wedges 108-2 arranged opposite to each other. The dual optical wedge system is configured to deflect the parallel laser beams from the same focus at the focal plane emitted from the transmission optical antenna system into the field of view of the tracking branch (for example, perpendicular to the target surface of the camera), and the dual optical wedge system is driven by the first driving device 110-1 and the second driving device 110-2 through the pivot 112. Because the field of view of the tracking branch is much smaller than that of the transmission optical antenna system, a scanning device is required to make the laser beam emitted from the transmission optical antenna system enter the field of view of the tracking branch to the greatest extent. Since the dual optical wedge system is used as a scanning device, no additional steering motor and galvanometer are required. Compared with the tracking and aiming fast reflection mirror with a smaller field of view and higher cost, the dual optical wedge system of the present invention has obvious advantages in 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, and a large-angle anti-reflection film is coated on the two planes of the optical wedge, forming a certain angle between the two planes, which is generally 10-30° according to the use requirements. After passing through the optical wedge, the parallel laser beam will be deflected by a certain angle. The deflection angle is determined by the refractive index of the material of the optical wedge and the wedge angle. In general, an optical wedge can complete a deflection of 5-15°. If the refractive index is 2, then an optical wedge with a wedge angle of 15° can achieve a deflection of 15°. Implementation data shows that for an optical system of laser communication equipped with dual optical wedges, a deflection of 30° can be achieved.

[0038] Figure 2 FIG. 4 is a schematic diagram showing the arrangement and optical path of the first objective lens group 102 according to some embodiments of the present invention. Figure 2 As shown, the first objective lens group 102 includes a first lens 202, a second lens 204, a third lens 206, and a fourth lens 208 sequentially placed along the laser light path. Light passing through each lens of the first objective lens group 102 is focused at the focal plane position 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 the optimization design process.

[0039] In some embodiments, the optimization design process for the material and shape of each lens in the first objective lens group 102 includes the following steps.

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

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

[0042] (3) The curvature radius, thickness and material of each lens in the first objective lens group 102 are set as variables, and corresponding restriction conditions are added.

[0043] (4) Optimize the first objective lens group 102 until various performances are close to the requirements, thereby obtaining the first objective lens group.

[0044] In some embodiments, the first lens 202 is a convex-planar positive lens, the second lens 204 is a meniscus positive lens, the third lens 206 is a double-concave negative lens, and the fourth lens 208 is a meniscus positive lens. The first lens 202 and the second lens 204 are crown glasses with low refraction and high dispersion, and the third lens 206 and the fourth lens 208 are flint glasses with high refraction and low dispersion. 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 plus or minus 5 degrees, and a total length of 120 mm. The first objective lens group 102 optimizes spherical aberration, primary coma and astigmatism as a whole through material matching, positive and negative meniscus symmetry, and double-bend configuration, and a small amount of high-order coma astigmatism and field curvature remain to be compensated.

[0045] Figure 3 FIG. 2 shows a schematic diagram of the arrangement and optical path of the second anti-objective lens group 106 according to some embodiments of the present invention. Figure 3 As shown, the second anti-objective lens group 106 includes a fifth lens 302, a sixth lens 304, a seventh lens 306 and an eighth lens 308 sequentially placed along the laser light path. The second anti-objective lens group 106 takes the focal plane of the first objective lens group 102 as the object plane and is conjugate to the infinite image plane. As described above, the material and shape selection of the second anti-objective lens group 106 including the fifth lens 302, the sixth lens 304, the seventh lens 306 and the eighth lens 308 sequentially placed along the laser light path is determined by the final result of the optimization design process.

[0046] In some embodiments, the optimization design process for the material and shape of each lens in the second anti-objective lens group 106 includes the following steps.

[0047] (1) According to the magnification and total length requirements of the transmission optical antenna system, a suitable initial configuration for the second anti-objective lens group 106 is selected, and the initial focal length and system aperture of the second anti-objective lens group 106 are clarified. For example, according to the magnification requirements of the transmission optical antenna system, the focal length of the second anti-objective lens group 106 is relatively small, which is the focal length of the first objective lens group 102 divided by the magnification. Considering the relatively large aperture and the large image field after beam reduction, for example but not limited to, a Zeiss eyepiece is selected as the initial configuration, and the double glued piece is split into two independent pieces.

[0048] (2) Keeping the first objective lens group 102 unchanged, the second anti-objective lens group 106 is connected behind the focal plane of the first objective lens group 102 according to the initial object distance of the Zeiss eyepiece.

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

[0050] (4) The curvature radius, thickness and material of each lens in the second anti-objective lens group 106 are set as variables, and corresponding restriction conditions are added.

[0051] (5) Optimize each lens until its performance is close to the requirements, and obtain the second anti-objective lens 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, the sixth lens 304 and the seventh lens 306 are made of high dispersion materials, and the eighth lens is made of low dispersion materials. The optical parameters of the second anti-objective lens group 106 composed of these lenses are, for example, a focal length of 30 mm and a field of view of plus or minus 30 degrees. The second anti-objective lens group 106 compensates for the residual aberration of the first objective lens group 102 through a symmetrical configuration and a meniscus lens.

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

[0054] In some embodiments, the overall optimization process for the combined arrangement 400 includes: under the conditions that the aperture, field of view, total length requirements and magnification of the transmissive optical antenna system remain unchanged, further optimizing the overall image quality (equivalent to "wave aberration"), and paying attention to device material cost, tolerance sensitivity, and image quality degradation caused by temperature changes, etc., to ultimately obtain a complete transmissive optical antenna system.

[0055] By adopting a combined optimization of telephoto objective and Zeiss eyepiece, the system can maintain good image quality within a 10° field of view without the need for a large-angle motor bandpass optical system to complete coarse tracking alignment, saving space.

[0056] Figure 5 1 shows the arrangement of the optical system under different viewing angles according to some embodiments of the present invention. Figure 5 As shown, the first optical wedge 108-1 and the second optical wedge 108-2 in the double optical wedge system are Figure 5 Parts (a) to (c) shown in the figure are placed at different relative angles. Figure 5 The portion (a) shown in FIG. 1 corresponds to a field of view of 0 degrees. Figure 5 Part (b) shown in FIG. 1 corresponds to a field of view of -3 degrees, Figure 5 The portion (c) shown in the figure corresponds to a 5 degree field of view, and accordingly, the deflection angle of the main 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 placement angle and rotate around the axis in the same direction and angular velocity, the normal direction of the optical wedge tilt surface also rotates around the main optical axis, so the scanning area is a circle.

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

[0058] In some embodiments, the driving device includes a driver for a dual optical wedge system, and the driver is configured to generate a relative placement angle and a co-directional rotation 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, and is equally discretized into a certain number, 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 driving until the scanning of any angle of view within the angle 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 angle of view, and drives the two optical wedges 108-1 and 108-2 to rotate 360 ​​degrees around the main optical axis at the same rotation angular velocity. In this way, the 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 a light spot entering the field of view of the tracking branch, it enters the fine tracking mode and adjusts the relative placement angle so that the light spot enters the center of the field of view (for example, the center of the camera) to maintain the fine tracking state.

[0061] Figure 6 FIG. 6 is a schematic diagram of a transmission device 600 for rotating an optical wedge according to some embodiments of the present invention. The transmission device 600 for the first optical wedge 108-1 is used as an example. Figure 6 As shown, 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 optical wedge 108-1, and the side surface is adjacent to the chamfered surface and the circular surface of the first optical wedge 108-1. The outer surface of the mirror base 608 is processed into a gear shape. The gear 606 is driven by the driving motor 602 through the transmission shaft 604, and drives the mirror base 608 to rotate through the track 610.

[0062] Other variations to the disclosed embodiments may be understood and effected by those skilled in the art in practicing the claimed invention by studying the drawings, the disclosure and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

[0063] The term "comprising" also includes embodiments where the term "comprising" means "consisting of.

[0064] The present invention also applies to a device, apparatus or system comprising one or more of the characterizing features described in the specification and / or shown in the drawings. The present invention also relates to a method or process comprising one or more of the characterizing features described in the specification and / or shown in the drawings. In addition, if a method or an embodiment of a method performed in a device, apparatus or system is described, it should be understood that the device, apparatus or system is suitable for or configured for (performing) a method or an embodiment of the method, respectively.

[0065] The various aspects discussed in this patent may be combined in order to provide additional advantages. In addition, those skilled in the art will appreciate that embodiments may be combined, and more than two embodiments may also be combined. In addition, some features may form the basis for one or more divisional applications.

Claims

1. An optical system for laser communication, characterized in that: include: A transmission optical antenna system, the transmission optical antenna system is located upstream of the double wedge system in the laser light path of the optical system, and comprises a first objective lens group and a second anti-objective lens group respectively composed of a plurality of lenses, the object plane of the second anti-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 to the focal plane of the first objective lens group through each lens of the first objective lens group, and the second anti-objective lens group is configured to shrink the laser beams from the same point at the focal plane of the first objective lens group and then emit them in parallel; A double optical wedge system, comprising two optical wedges arranged opposite to each other, wherein the double optical wedge system is configured to deflect the parallel laser beam emitted from the transmission optical antenna system into the field of view of the tracking branch, and the double optical wedge system is driven by a driving device; as well as The driving device includes a driver for the dual optical wedge system, and the driver is configured to generate a relative placement angle and a same-direction rotation 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 further comprises: The turning mirror is located at the focal plane of the first objective lens group, and is configured to reflect the laser beam emitted from the first objective lens group toward the second anti-objective 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 wave 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 anti-objective lens group and the magnification of the transmission optical antenna system is equal to the focal length of the first objective lens group, the length of the second anti-objective lens group is less than or equal to 1 / 3 of the length of the transmission optical antenna system, the second anti-objective lens group is afocal in image space and the wave aberration of the second anti-objective 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-flat positive lens, a first meniscus positive lens, a double concave negative lens and a second meniscus positive lens which are sequentially placed along the laser light path.

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

7. The optical system according to claim 4, characterized in that The second anti-objective lens group includes a plano-convex positive lens, a convex-planar positive lens, a meniscus positive lens and a meniscus negative lens placed in sequence along the laser light path, wherein the dispersion capabilities of the plano-convex positive lens, the convex-planar positive lens and the meniscus positive lens are all higher than the dispersion capability 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 double 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 driving device is configured to: repeat the following driving until scanning of any viewing angle within the viewing angle range 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 viewing angle, and drives the two optical wedges to rotate 360 ​​degrees around the main optical axis at the same rotation angular velocity.

10. The optical system according to claim 9, characterized in that The side surface of each of the two optical wedges is covered by a mirror seat, and the side surface is adjacent to the chamfered surface and the circular surface of the optical wedge. The outer surface of the mirror seat is gear-shaped. The driving device includes two driving motors, and the two driving motors respectively drive a gear. The gear and the mirror seat form a transmission through a track.

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