Large-aperture spliced telescope adjusting device and adjusting method thereof

Abstract

The invention belongs to the field of astronomical telescopes, and particularly relates to a large-aperture spliced telescope adjusting device and method, and the method comprises the steps: starting a light source module, providing a far-field illumination light beam for a spliced primary mirror, and carrying out the confocal adjustment of each sub-mirror through an adjusting mechanism according to the far-field illumination light beam; the light source switching module is used for providing a near-field illumination light beam for the spliced primary mirror, and the near-field illumination light beam is split into two separated sub light beams by the pyramid mirror after penetrating through a splicing seam of the spliced primary mirror; performing dispersion on all the sub-beams through a dispersion prism, and converging the dispersed sub-beams through an achromatic lens to form dispersion stripes; the phase difference of the dispersion fringes is extracted through the camera, and co-phase adjustment is carried out on the sub-mirrors through the adjusting mechanism according to the phase difference of the dispersion fringes. According to the invention, high-precision and high-flux spectral response calibration and co-phase detection of the large-aperture spliced telescope can be realized, so that reliable technical support is provided for construction and operation of a next-generation giant astronomical telescope.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of astronomical telescopes, and particularly relates to a large-aperture spliced telescope adjusting device and an adjusting method thereof. BACKGROUND

[0002] With the development of astronomical research towards deeper space and more detailed observation, the spectral response calibration technology of the extremely large aperture telescope is put forward with unprecedented high requirements. High-precision spectral measurement is the premise for realizing the core scientific goals such as redshift estimation and element abundance analysis.

[0003] At present, the spectral response detection and co-phasing detection of large-aperture optical systems mainly face the following technical bottlenecks: Uniformity problem: The internal coating uniformity and edge consistency of the traditional large-aperture integrating sphere as a standard Lambertian radiator are difficult to guarantee, which leads to the deviation of the outgoing light field distribution from the ideal Lambert characteristic, and cannot provide a high-uniformity illumination light source for high-precision calibration.

[0004] Cost and flexibility dilemma: The cost of manufacturing a parallel light pipe with an aperture of more than 2 meters is extremely high, the cycle is long and the movement is difficult, which cannot meet the rapid and flexible detection needs of future large space telescopes. At the same time, the construction of a giant integrating sphere also faces the challenges of cost and technology.

[0005] Complexity of co-phasing detection: For spliced mirror telescopes, realizing co-phasing between sub-mirrors (i.e. eliminating piston error) is the key to ensuring imaging quality. Traditional co-phasing detection technology is often complex, low throughput, difficult to realize high-throughput and high-efficiency detection, and lacks effective compensation means for environmental factors such as atmospheric dispersion.

[0006] Limited detection accuracy: The existing detection methods have deficiencies in stray light suppression and modal noise elimination, for example, when using a multi-mode optical fiber, intermodal interference and speckle will be generated, which affects the uniformity of the light field and the final signal-to-noise ratio, thereby limiting the further improvement of the detection accuracy. SUMMARY

[0007] Therefore, the present application aims to provide a large-aperture spliced telescope adjusting device and an adjusting method thereof, which realizes high-precision and high-throughput spectral response calibration and co-phasing detection of large-aperture spliced telescopes, thereby providing reliable technical support for the construction and operation of the next generation of giant astronomical telescopes.

[0008] To achieve the above-mentioned purpose, the technical solution of the present application is as follows: A large-aperture spliced telescope adjusting device, the large-aperture spliced telescope comprising a spliced primary mirror, the spliced primary mirror being spliced by a plurality of sub-mirrors, and a splicing gap being formed between the plurality of sub-mirrors, comprising: a light source module for providing a near-field illumination light beam and a far-field illumination light beam for the mosaic primary mirror; a plurality of prisms, each prism being arranged at a corresponding one of the plurality of seams, and each prism being configured to split the near-field illumination light beam emitted from each seam into two separate sub-beams; a dispersion element arranged in an emission direction of the prisms and configured to disperse each of the sub-beams; a plurality of achromatic lenses, each achromatic lens being arranged in an emission direction of the dispersion element and configured to converge each of the dispersed sub-beams to form a dispersion fringe; a plurality of cameras, each camera being arranged in an emission direction of the achromatic lenses and configured to capture an image of the dispersion fringe and extract a phase difference of the dispersion fringe; an adjustment mechanism connected to each of the cameras and the sub-mirrors, and configured to co-phase adjust each of the sub-mirrors according to the phase difference of the dispersion fringe, and to co-focus adjust each of the sub-mirrors according to the far-field illumination light beam.

[0009] Further, the large-aperture mosaic telescope adjustment device further comprises a rotating mechanism, the dispersion element is mounted on the rotating mechanism, and the dispersion element is driven to rotate around its own axis by the rotating mechanism to realize atmospheric dispersion compensation.

[0010] Further, the light source module comprises a near-field light source and a far-field light source, the near-field light source is configured to provide the near-field illumination light beam, and the far-field light source is configured to provide the far-field illumination light beam.

[0011] Further, the dispersion element comprises a dispersion prism and / or a dispersion lens.

[0012] Further, a mirror is arranged on one side of each seam of the light source module, and a half-transmission half-reflection mirror is arranged between each seam and the corresponding prism, a part of the near-field illumination light beam emitted from each seam is transmitted to the camera, and the other part is reflected to the mirror and then re-transmitted through the seam to finally be incident on the camera.

[0013] Further, a grating is arranged between each achromatic lens and the corresponding camera, the convergent light passing through the achromatic lens is incident on the grating for dispersion and then captured by the camera.

[0014] Further, a microlens array is arranged between each grating and the corresponding camera, the light beam dispersed by the grating is converged by the microlens array and then captured by the camera.

[0015] Further, the large-aperture mosaic telescope adjustment device further comprises a secondary mirror truss for mounting a secondary mirror, a laser is arranged on the secondary mirror truss, the laser emitted by the laser is reflected by the mosaic primary mirror to the secondary mirror, and then transmitted through the slit to be incident on the tip of the prism.

[0016] A large-aperture telescope adjustment method is realized by using the large-aperture telescope adjustment device, and comprises the following steps: S1: turning on the light source module to provide a far-field illumination beam for the spliced primary mirror, and adjusting the confocal of each sub-mirror according to the far-field illumination beam through the adjusting mechanism; S2: switching the light source module to provide a near-field illumination beam for the spliced primary mirror, and the near-field illumination beam is split into two separated sub-beams by the prism after passing through the joint seam of the spliced primary mirror; S3: dispersing all the sub-beams through the dispersion prism, and converging each dispersed sub-beam through the achromatic lens to form a dispersion stripe; S4: extracting the phase difference of the dispersion stripe through the camera, and adjusting the in-phase of each sub-mirror according to the phase difference of the dispersion stripe through the adjusting mechanism.

[0017] Further, the image sharpness value of the dispersion stripe image is calculated, and the maximum value of the image sharpness is found through scanning.

[0018] Compared with the prior art, the present application can achieve the following beneficial effects: 1. High-precision and high-efficiency in-phase detection and correction is realized: by introducing a prism to separate the light beam at the joint seam of the spliced mirror, and combining with the subsequent dispersion element and achromatic lens, the dispersion stripe can be directly generated, which is easy to analyze. This method converts the complex wavefront sensing into intuitive stripe image processing, not only simplifies the detection process, but also quickly and accurately extracts the phase difference information, providing a high-efficiency and reliable feedback for the in-phase adjustment of the spliced mirror of the large-aperture telescope, ensuring that the imaging quality of the optical system approaches the diffraction limit.

[0019] 2. Active atmospheric dispersion compensation ability, stronger environmental adaptability: by rotating the dispersion element, the atmospheric dispersion caused by the pitch of the large-aperture telescope can be compensated in real time. This feature makes the device particularly suitable for ground-based large-aperture telescopes, effectively suppressing the negative impact of atmospheric dispersion on detection accuracy and final imaging quality, and widening the application scenarios of the detection method. BRIEF DESCRIPTION OF DRAWINGS

[0020] The accompanying drawings, which form a part of the present application, are used to provide a further understanding of the present application, and the illustrative embodiments of the present application and their description serve the purpose of explaining the present application. The accompanying drawings do not constitute an inappropriate limitation on the present application. In the drawings: Figure 1 A structure diagram of the large-aperture telescope adjustment device described in the embodiment of the present application; Figure 2 A confocal adjustment diagram of the spliced primary mirror described in the embodiment of the present application; Figure 3 This is a schematic diagram of the phase adjustment of the splicing primary mirror as described in an embodiment of the present invention.

[0021] Explanation of reference numerals in the attached figures: 1. Sub-lens; 2. Prism lens; 3. Dispersive element; 4. Achromatic lens; 5. Camera. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0024] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0025] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "assembly," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] like Figure 1As shown, this invention provides a large-aperture spliced ​​telescope adjustment device. The large-aperture spliced ​​telescope includes a splicing primary mirror and a secondary mirror. The secondary mirror is mounted on the secondary mirror truss, and the splicing primary mirror is mounted on the primary mirror truss. The splicing primary mirror is composed of multiple sub-mirrors 1 spliced ​​together, with seams formed between the multiple sub-mirrors 1. The large-aperture spliced ​​telescope adjustment device includes a light source module, a prism mirror 2, a dispersive element 3, an achromatic lens 4, a camera 5, and an adjustment mechanism.

[0028] The light source module includes a near-field light source and a far-field light source. The near-field light source is used to provide a near-field illumination beam for the stitching master mirror, and the far-field light source is used to provide a far-field illumination beam for the stitching master mirror.

[0029] The number of pyramidal mirrors 2 is the same as the number of seams. Each pyramidal mirror 2 is set at each seam. The near-field illumination beam emitted from each seam is split into two separate sub-beams by the pyramidal mirror 2.

[0030] The dispersive element 3 is positioned in the exit direction of the prism 2 to disperse each beam of light. The dispersive element 3 can be a dispersive prism with high dispersion characteristics, a dispersive lens with low dispersion characteristics, or a combination of a dispersive prism and a dispersive lens.

[0031] The number of achromatic lenses 4 is the same as the number of seams. Each achromatic lens 4 is set in the emission direction of the dispersive element 3 to converge the various sub-beams that have passed through the dispersive element to form dispersive fringes.

[0032] The number of cameras 5 is the same as the number of seams. Each camera 5 is set in the exit direction of the achromatic lens 4 to acquire dispersive fringe images and extract the phase difference of the dispersive fringes.

[0033] The adjustment mechanism is connected to the camera 5 and each sub-mirror 1 respectively, and is used to perform co-phase adjustment on each sub-mirror 1 according to the phase difference of the dispersion fringes, and to perform confocal adjustment on each sub-mirror 1 according to the far-field illumination beam.

[0034] The adjustment device for the large aperture modular telescope also includes a rotating mechanism. The dispersive element 3 is mounted on the rotating mechanism, which drives the dispersive element 3 to rotate around its own axis to achieve atmospheric dispersion compensation.

[0035] A reflector is provided on one side of each seam located in the light source module 1. A semi-transparent and semi-reflective mirror is provided between each seam and the corresponding pyramidal mirror 2. Part of the near-field illumination beam emitted from each seam is transmitted to the camera 5, and the other part is reflected to the reflector. After being reflected by the reflector, it passes through the seam again and finally enters the camera 5.

[0036] A grating is placed between each achromatic lens 4 and its corresponding camera 5. The converging light from the achromatic lens 4 is incident on the grating for dispersion, and then captured by the camera 5 to form an image. The purpose of setting up the grating is to achieve a wide range of measurements through multi-wavelength combinations, thus overcoming the shortcomings of single-wavelength measurements.

[0037] In order to improve the energy received by the camera 5, a microlens array is set between each grating and the corresponding camera 5. The light beam dispersed by the grating is converged by the microlens array, so that the light energy is concentrated and then collected by the camera 5, thereby improving the signal-to-noise ratio.

[0038] A laser is also installed on the secondary mirror truss. The laser beam emitted by the laser is incident on sub-mirror 1, reflected by sub-mirror 1 to the secondary mirror, and then reflected by the secondary mirror to pass through the slit and enter the tip of the pyramidal mirror 2. If the laser beam is not at the tip of the pyramidal mirror 2, the position of the secondary mirror is adjusted until the laser beam is at the tip of the pyramidal mirror 2 to avoid the dynamic range being destroyed by the overall tilt.

[0039] This invention provides a method for adjusting a large-aperture modular telescope, which utilizes the aforementioned large-aperture modular telescope adjustment device. The method includes the following steps: S1: Turn on the light source module to provide a far-field illumination beam for the main mirror of the splicing, and adjust the confocal adjustment of each sub-mirror according to the far-field illumination beam through the adjustment mechanism.

[0040] S2: Switch the light source module to provide a near-field illumination beam for the splicing master mirror. After passing through the splicing seam of the splicing master mirror, the near-field illumination beam is split into two separate sub-beams by the prism mirror.

[0041] S3: Dispersion of all sub-beams is achieved through a dispersive prism, and the dispersed sub-beams are converged through an achromatic lens to form dispersion fringes.

[0042] Atmospheric dispersion compensation is achieved by rotating the dispersive element around its own axis through a rotating mechanism.

[0043] S4: The phase difference of the dispersion fringes is extracted by the camera, and then the adjustment mechanism is used to adjust the phase difference of the dispersion fringes to achieve co-phase adjustment of each sub-mirror.

[0044] The confocal adjustment method is as follows: The dispersion fringes acquired by the camera are a special type of interference fringe. In the interference fringe image, the dark area corresponding to the stitching seam should be located in the middle of the camera target surface, meaning the bright areas on both sides of the dark area are symmetrical. This indicates that the two sub-mirrors on both sides of the stitching seam are confocal. Therefore, when observing the image acquired by the camera, if the bright areas on both sides of the dark area are asymmetrical, the sub-mirrors on both sides of the stitching seam are not confocal. In this case, it is necessary to adjust the spatial pose of the sub-mirrors on both sides of the stitching seam to make the bright areas on both sides of the dark area symmetrical, thus achieving confocal adjustment of the sub-mirrors on both sides of the stitching seam.

[0045] like Figure 2 As shown, from (a1) to (d1), the integrity and symmetry of the pattern gradually improve, indicating that the performance or control parameters of the optical system are being optimized step by step, making the light intensity distribution more regular and predictable. The method of co-phase adjustment is as follows: calculate the light intensity difference between the two sub-mirror regions through the interference fringe image, adjust the two sub-mirrors according to the light intensity difference, and finally achieve co-phase.

[0046] like Figure 3 As shown, the yellow-marked stripes are a direct result of phase coherence superposition. The change in stripe pattern from (a2) to (d2) reflects the difference in the degree of phase matching under co-phase modulation, which in turn leads to different interference characteristics.

[0047] For the extended target, the image sharpness value of its dispersion fringe image after dispersion is calculated. Then, by scanning, the maximum image sharpness value is found to achieve co-phase between the two sub-mirrors under the extended target.

[0048] The basic principle of spectral domain response detection is: Based on the reversibility of light and the impulse function of the pupil plane, the system transfer function is measured by performing a Fourier transform at the focal plane. By using the impulse input at the pupil, a response is formed at the focal plane. By using the convolution principle of the surface source, the response function of the entire system is reconstructed by moving the output light source to different locations.

[0049] In terms of system architecture, the system outputs broadband light from a broadband light source, and the output frequency band is selected by a wavelength division multiplexer before being emitted to the system's focal plane via a coupler. In practical use, firstly, the center position of the projection is confirmed using a central waveguide and lens group; secondly, the projection range of the system is confirmed using edge waveguides. Based on the changes in the projection shape and the measurement of geometric angles, the distribution of the projected light on the projection target surface can be estimated. Using the contrast of the entire surface as the optimization objective, a gradient descent method is used for calculation, and adjustments are made to ultimately make the light intensity projection contrast on the surface as uniform as possible. During actual installation, multiple small-aperture systems with known precision and detectors are used for prior calibration of the light field. Illuminance when the light source directly illuminates the surface (inverse square law of distance). Point light source average luminous intensity microvan distance for , right The solid angle subtended by the point is , normal and solid angle The included angle of the axis is .

[0050] By the definition of solid angle, we have: ; From the expression for luminous intensity, we get: ; Therefore, the area Illuminance for: ; That is, when a point light source illuminates a micro-area, the illuminance of the micro-area is compared to the luminous intensity of the point light source. Proportional to the distance from the point light source to the micro-area It is inversely proportional to the square and is also related to the angle between the normal to the infinitesimal area and the direction of the illuminating beam. It is proportional to the cosine when irradiated perpendicularly ( During grazing ( ), the illuminance is at its maximum; during grazing ( ), with an illuminance of 0.

[0051] When the light source is a surface light source, the illuminance of the illuminated surface is still inversely proportional to the square of the distance between the surface and the light source.

[0052] The micro-emitting surface representing the light source is located at a distance of of Illumination on the surface .

[0053] ; In the formula, The brightness of the light source, , Each is a light-emitting surface and the surface being illuminated normal and distance The angle between directions. The above formula shows that when a surface light source illuminates a small area, the illuminance of the illuminated surface is related to the luminance L of the surface light source and the area. Proportional to distance Inversely proportional to, and the angle between, the normals of the two surfaces and the direction of the irradiated beam. , The illuminance is directly proportional to the cosine of the distance. Compared with the illuminance formula of a point light source, the difference between the two is that the illuminance caused by a point light source is directly proportional to the luminous intensity, while the illuminance caused by a surface light source is directly proportional to the luminous brightness and the area of ​​the light source. The similarity between the two is that they are both inversely proportional to the square of the distance and are related to the inclination of the surface.

[0054] First consider the illuminance of the image point on the axis. The figure shows an imaging optical system where only the entrance pupil and exit pupil are drawn. and These represent the minute areas of the object and image near the point on the axis, respectively; the object-side and image-side aperture angles are respectively... , The object plane and image plane brightness are respectively and If the object is considered as a cosine radiator, then its infinitesimal area... The aperture angle to the plane is The luminous flux emitted within the solid angle range can be calculated using the following formula.

[0055] ; Right now .

[0056] Similarly, from the exit pupil to the image plane The luminous flux over the micro-area is: .

[0057] Image plane illuminance is: .

[0058] According to the law of light transmission Thus, the image surface illuminance is obtained. .

[0059] When the refractive index of the medium in the object space is the same, that is hour, .

[0060] Next, examine the illuminance of off-axis image points. Off-axis image points The angle between the principal ray and the optical axis is , The angle is called the image-side field of view angle of the off-axis image point.

[0061] When the object surface has uniform brightness, the off-axis image point Illuminance can be expressed by the previous illuminance formula as follows: .when When the size is smaller, then: .

[0062] therefore, ,Right now .

[0063] Therefore, the illuminance of off-axis image points varies with the field of view angle. The increase and according to The regularity decreases.

[0064] The detection accuracy analysis is as follows: An array of reflectors is placed at the exit pupil of the system during splicing. This array consists of a single Lambertian radiator and has a direction adjustment and centering mechanism to ensure that the light returns along its original path. Since the intensity of the light reflected by the Lambertian radiator varies with the reflection angle in a cosine manner, the accuracy of the adjustment mechanism can be deduced based on the cosine intensity variation law.

[0065] During the detection process, the adjustment mechanism can be actively subjected to alternating carrier waves. Based on the carrier wave changes, the requirements for absolute positioning accuracy and suppression of stray light can be reduced, and in-situ detection can be achieved. This method can reduce the construction requirements of large-aperture integrating spheres. Large-aperture integrating spheres require the formation of a uniform single radiator on the surface, thus necessitating complex optical paths or multiple reflections. Here, laser multi-path interference is used to form fringes, improving projection uniformity. Phase fluctuations between multiple projections are used to achieve light intensity homogenization, and combined with long-term integration, projection uniformity is further improved. In single-mode fiber, only the fundamental mode propagates; therefore, from the perspective of degree-of-freedom restriction, only the signal intensity attenuates. However, multimode fiber has multiple modes propagating simultaneously. After traveling the same distance, different modes exhibit different attenuation modes and states; therefore, multiple mode combinations will appear at the output end.

[0066] A multimode fiber with a mode scrambler is employed to suppress intermode interference and large-area speckle caused by mode separation. An optical switch rapidly switches between different fields of view, and averaging is achieved through long-term integration by the end detector.

[0067] The study on multi-field-of-view segmentation detection path of fiber optic interconnected interferometric array is based on the dual coupling of the field of view of the fiber optic interconnected system under the interference mechanism and the numerical aperture of the fiber. By combining the field of view segmentation of the prism and the optical flow segmentation of the few-mode device, the sensing flux is effectively expanded. Real-time high-throughput wavefront sensing and fringe tracking are achieved by guiding the target near the satellite.

[0068] Based on the reversible characteristics of the synthesized optical path at the integrated interferometer end, the internal metric architecture of the system based on shearing interferometry is optimized to construct an integrated architecture for alignment / sensing multiplexing.

[0069] This research on the fabrication and error calibration methods of wavefront sensing few-mode devices is based on aperture coding combined with few-mode optical fibers. It utilizes a few-mode device mode conversion calibration method to achieve wavefront calculation. Furthermore, based on precise pointing correction, aperture coding and optical fibers are used to detect the co-phase state of splicing mirrors and low-order wavefronts.

[0070] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0071] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A large-aperture modular telescope adjustment device, the large-aperture modular telescope comprising a modular primary mirror and secondary mirrors, the modular primary mirror being composed of multiple sub-mirrors joined together, with seams formed between the multiple sub-mirrors, characterized in that... include: The light source module is used to provide near-field and far-field illumination beams for the stitching master mirror; The number of prisms is the same as the number of seams. Each prism is set at each seam. The near-field illumination beam emitted from each seam is split into two separate sub-beams by the prisms. A dispersive element is positioned in the exit direction of the prism mirror to disperse each beam of light. Achromatic lenses, the number of which is the same as the number of seams, are respectively set in the emission direction of the dispersive element to converge the individual sub-beams that have passed through the dispersive element to form dispersive fringes. The number of cameras is the same as the number of seams. Each camera is set in the exit direction of the achromatic lens to acquire images of dispersion fringes and extract the phase difference of the dispersion fringes. The adjustment mechanism, which is connected to the camera and each sub-lens respectively, is used to perform co-phase adjustment of each sub-lens based on the phase difference of the dispersion fringes, and to perform confocal adjustment of each sub-lens based on the far-field illumination beam.

2. The large-aperture modular telescope adjustment device according to claim 1, characterized in that, It also includes a rotating mechanism, on which the dispersive element is mounted. The rotating mechanism drives the dispersive element to rotate around its own axis to achieve atmospheric dispersion compensation.

3. The large-aperture modular telescope adjustment device according to claim 1, characterized in that, The light source module includes a near-field light source and a far-field light source. The near-field light source is used to provide a near-field illumination beam, and the far-field light source is used to provide a far-field illumination beam.

4. The adjustment device for a large-aperture modular telescope according to claim 1, characterized in that, Dispersive elements include dispersive prisms and / or dispersive lenses.

5. The large-aperture modular telescope adjustment device according to claim 1, characterized in that, A semi-transparent, semi-reflective mirror is placed between each seam and the corresponding pyramidal mirror. Part of the near-field illumination beam emitted from each seam is transmitted to the camera, and the other part is reflected to the secondary mirror. After being reflected by the secondary mirror, it passes through the seam again and finally enters the camera.

6. The adjustment device for a large-aperture modular telescope according to claim 1, characterized in that, A grating is placed between each achromatic lens and its corresponding camera. The converging light from the achromatic lens is incident on the grating for dispersion and then captured by the camera.

7. The large-aperture modular telescope adjustment device according to claim 6, characterized in that, A microlens array is set between each grating and its corresponding camera. The light beam dispersed by the grating is converged by the microlens array and then captured by the camera.

8. The large-aperture modular telescope adjustment device according to claim 1, characterized in that, It also includes a secondary mirror truss for mounting the secondary mirror, on which a laser is installed. The laser emitted by the laser is reflected by the splicing primary mirror to the secondary mirror, and then reflected by the secondary mirror through the slit before entering the tip of the pyramidal mirror.

9. A method for adjusting a large-aperture modular telescope, implemented using the large-aperture modular telescope adjustment device as described in claim 1, characterized in that... Includes the following steps: S1: Turn on the light source module to provide a far-field illumination beam for the main mirror of the splicing, and adjust each sub-mirror according to the far-field illumination beam through the adjustment mechanism; S2: Switch the light source module to provide a near-field illumination beam for the splicing master mirror. After passing through the splicing seam of the splicing master mirror, the near-field illumination beam is split into two separate sub-beams by the prism mirror. S3: Dispersion of all sub-beams is achieved through a dispersive prism, and the dispersed sub-beams are converged through an achromatic lens to form dispersion fringes. S4: Acquire dispersion fringe images through a camera, extract the phase difference of the dispersion fringes, and then adjust each sub-mirror according to the phase difference of the dispersion fringes through an adjustment mechanism.

10. The adjustment method for a large-aperture modular telescope according to claim 9, characterized in that, Calculate the image sharpness value of the dispersive fringe image by scanning to find the maximum image sharpness value.

Images