Multi-channel switching device and method for astronomical terminal instruments

Abstract

This invention discloses a multi-channel switching device and method for astronomical terminal instruments. The device includes a frame, fiber optic mounts, a switching device, an adjustment device, and a precision calibration device. Utilizing the fixed geometric positional relationship between the incident fiber and the switching device, a motor-driven rotating shaft moves a reflector, ensuring that incident fibers at different positions on different fiber optic mounts are horizontally introduced into the terminal instrument. Errors in the incident light and the switching mechanism are calibrated using a tip / tilt mirror. The motor-driven intelligent unit switches between different incident fibers, avoiding high-precision position switching for each fiber optic source, reducing switching difficulty, and decreasing the degrees of freedom of the moving mechanism. This method achieves fully automatic switching of incident fibers, improving switching efficiency and accuracy, while avoiding the impact on equipment performance caused by manual switching requiring on-site intervention. This invention's device can simultaneously handle switching between direct incident light from folded-axis telescopes and fiber optic incident light.

Description

Technical Field

[0001] This invention belongs to the field of astronomical observation equipment technology, and in particular to a multi-channel switching device and method for astronomical terminal instruments. Background Technology

[0002] Astronomical terminal instruments refer to the general term for instruments and equipment used to observe celestial bodies and demonstrate celestial phenomena. Commonly used astronomical instruments include stellar astronomical instruments, radio astronomical instruments, and solar astronomical instruments. For stellar observation, commonly used astronomical terminal instruments include spectrometers, coronagraphs, and direct imagers.

[0003] With the advancement of science and technology, not only are superior performance requirements for astronomical instruments demanded, but also more advanced functions from terminal instruments. To meet the multifunctional needs of astronomical observation, different target lights are often introduced into the equipment via optical fibers for scientific observation. Simultaneously, the instruments themselves require calibration and system calibration, resulting in highly complex incident systems for terminal instruments. Existing incident systems are either too large or lack the precision required for higher accuracy.

[0004] In summary, developing a switching system with higher precision, greater reliability, and smaller weight and size is an urgent problem to be solved by those skilled in the art when switching between different functions of a multifunctional terminal instrument. Summary of the Invention

[0005] The purpose of this invention is to provide an incident device with higher precision and reliability, and smaller weight and size, for switching the light source into the multifunctional fiber optic terminal instrument of a high-precision compact astronomical telescope.

[0006] The technical solution to achieve the purpose of this invention is: a multi-channel switching device for astronomical terminal instruments, the device comprising a frame, an optical fiber mount, a switching device, an adjustment device, and a precision calibration device;

[0007] The fiber optic mounting base is fixedly installed on the upper end of the frame. Multiple optical fibers are arranged on the fiber optic mounting base, and the outgoing light rays of the optical fibers are in the same incident plane.

[0008] The switching device is installed at the lower end of the frame and below the fiber optic mounting base. It includes a reflector group and is used to switch between different types of optical fibers, thereby allowing the light emitted from different types of optical fibers to enter the terminal instrument.

[0009] The adjustment device is used to adjust the position of the optical fiber holder in a direction perpendicular to the incident plane;

[0010] The precision calibration device is used to allow the optical fiber output light to enter the terminal instrument, and at the same time, it is used to correct the switching error of the switching device and the error caused by other noise loads based on the error feedback result of the camera inside the terminal instrument.

[0011] The reflector group includes reflectors at different angles, and the outgoing light from different types of optical fibers corresponds to reflectors at different angles. After being reflected by the reflectors, the outgoing light from the optical fibers forms a horizontal outgoing light beam that is incident on the precision calibration device. After being calibrated and reflected by the precision calibration device, it enters the terminal instrument.

[0012] Furthermore, the frame includes an upper frame and support feet, with a pair of support feet fixedly installed at both ends of the bottom of the upper frame; the upper frame is a hollow structure, and the optical fiber fixing base is fixedly installed in the upper frame.

[0013] Furthermore, the switching device also includes an intelligent driving unit and a motor; the motor is fixedly installed on one side of one of the support feet, the intelligent driving unit is installed between a pair of support feet and below the fiber optic mounting base, and the reflector assembly is installed on the slider of the intelligent driving unit; the output shaft of the motor drives the stator of the intelligent driving unit to rotate, and the rotor of the intelligent driving unit drives the slider to move, thereby driving the reflector assembly to move in a direction perpendicular to the incident plane, so that different types of fiber optic light are reflected by reflectors at different angles and then emitted horizontally, realizing fiber optic switching.

[0014] Furthermore, the adjustment device includes an adjusting screw and leaf springs. A pair of leaf springs are respectively installed on both sides of the fiber optic mounting base and connected to the upper frame, and are respectively located on both sides of the incident plane. The compression direction of the leaf springs is perpendicular to the incident plane. A pair of pressure plates are provided on the upper frame, respectively located above the pair of leaf springs. The tail end of the adjusting screw passes through the threaded hole on the pressure plate and abuts against the leaf spring. By adjusting the adjusting screw, the leaf spring is deformed to generate elastic force applied to the fiber optic mounting base, pushing the position of the fiber optic mounting base to move, thereby realizing the adjustment of the position of the incident fiber.

[0015] Furthermore, the adjustment device also includes a set wire structure for fine-tuning the position of the fiber optic fixture; the set wire structure includes a pair of set wires, one end of which is respectively installed on two sides of the upper frame parallel to the incident plane, and the other end abuts against the adjustment side of the fiber optic fixture, the adjustment side being parallel to the incident plane; by adjusting the set wires on both sides of the upper frame, the fiber optic fixture moves horizontally along a direction perpendicular to the incident plane, thereby achieving fine-tuning of the position of the incident fiber.

[0016] Furthermore, a guide groove is provided on the side wall of the upper frame, and the fixed end of the optical fiber fixing seat is placed in the guide groove. The side wall of the guide groove positions the fixed end, and the optical fiber fixing seat can slide along the guide groove. A first slot is provided on the inner side wall of the upper frame parallel to the incident plane, and a second slot is provided on the side wall of the optical fiber fixing seat located on both sides of the incident plane. The two ends of the leaf spring are respectively engaged in the first slot and the second slot.

[0017] Furthermore, the precision calibration device includes a Tip / Tilt mirror and a Tip / Tilt actuator; the Tip / Tilt mirror is used to reflect the reflected light from the mirror group into the terminal instrument; the Tip / Tilt actuator is used to correct the switching error of the switching device and the error caused by other noise loads based on the feedback error result of the camera inside the terminal instrument, so that the reflected light from the mirror group accurately enters the terminal instrument.

[0018] Furthermore, the motor is an encoder motor, and the output shaft of the encoder motor has a zero position and a switching position, which accurately calibrates the switching position of different incident optical fibers corresponding to different positions; when the output shaft is in the zero position, the outgoing light of the optical fiber installed in the center position is reflected by the reflector to form a horizontal outgoing light; when the output shaft is in the switching position, the normal of the reflecting surface of the reflector coincides with the angle bisector of the included angle; the included angle is the angle formed by the outgoing light of the optical fiber and the horizontal line in the incident plane.

[0019] A method for multi-channel switching of astronomical terminal instruments based on the aforementioned device, the method comprising the following steps:

[0020] Step 1: Calibrate the zero position and switching position of the encoder motor's output shaft, and obtain the step value of each switching position relative to the zero position;

[0021] Step 2: Adjust the output shaft of the encoder motor to the zero position;

[0022] Step 3: Switch to different step values ​​to introduce the incident light from different optical fibers into the terminal instrument.

[0023] Furthermore, the method also includes:

[0024] Step 4: The monitoring CCD installed in the terminal instrument images the incident light and performs image processing. The monitoring CCD feeds back the incident error value of the image to the Tip / Tilt control system to correct the orientation of the incident light.

[0025] Compared with the prior art, the significant advantages of this invention are:

[0026] 1) By utilizing the fixed geometric positional relationship between the incident optical fiber and the switching device, the switching of different optical fiber light sources is completed through the one-dimensional rotation of the motor's output shaft. This avoids the need for high-precision position switching of each target optical fiber light source, reduces the difficulty of switching, reduces the degree of freedom of the motion mechanism, and thus reduces the size and weight of the device, thereby reducing costs.

[0027] 2) The optical fiber holder can be moved horizontally perpendicular to the incident plane by adjusting the adjustment device, thereby realizing fine adjustment of the position of the incident optical fiber. Its structure is simple and improves the adjustment accuracy of the position of the incident optical fiber.

[0028] 3) The switching system's stability is improved by dynamically compensating for switching errors and environmental noise interference through Tip / Tilt mirrors.

[0029] 4) It can accommodate different telescope incident channels, such as fiber optic incident and folded-axis telescope incident.

[0030] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a multi-channel switching device for astronomical terminal instruments in an embodiment of the present invention;

[0032] Figure 2 yes Figure 1 The first sectional view;

[0033] Figure 3 yes Figure 1 The second sectional view. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0035] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0036] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0037] In one embodiment, combined Figure 1 and Figure 3 A multi-channel switching device for astronomical terminal instruments is provided for switching the incidence of different targets and light sources. The device includes a frame, an optical fiber holder 2, a switching device, an adjustment device, and a precision calibration device.

[0038] The fiber optic mounting base is fixedly installed on the upper end of the frame. Multiple optical fibers are arranged on the fiber optic mounting base, and the outgoing light rays of the optical fibers are in the same incident plane.

[0039] The switching device is installed at the lower end of the frame and below the fiber optic mounting base. It includes a reflector group 10 and is used to switch between different types of optical fibers, thereby allowing the light emitted from different types of optical fibers to enter the terminal instrument.

[0040] The adjustment device is used to adjust the position of the optical fiber holder in a direction perpendicular to the incident plane;

[0041] The precision calibration device is used to allow the optical fiber output light to enter the terminal instrument, and at the same time, it is used to correct the switching error of the switching device and the error caused by other noise loads based on the error feedback result of the camera inside the terminal instrument.

[0042] The reflector group includes reflectors at different angles, and the outgoing light from different types of optical fibers corresponds to reflectors at different angles. After being reflected by the reflectors, the outgoing light from the optical fibers forms a horizontal outgoing light beam that is incident on the precision calibration device. After being calibrated and reflected by the precision calibration device, it enters the terminal instrument.

[0043] The device of this invention can simultaneously switch between multiple modes, including direct incident and fiber optic incident via a folded-axis telescope.

[0044] It is worth noting here that the machining accuracy of the fiber optic connector mounting holes on the fiber optic mount 2 plays a crucial role in the switching accuracy of the incident device. If the machining accuracy of the fiber optic connector mounting holes is low, it directly leads to low installation position accuracy of the incident fiber 1, making it difficult to achieve high-precision position switching of multiple incident fibers.

[0045] Here, preferably, the top of the fiber optic mounting base 2 is either flat or arc-shaped. To ensure high machining accuracy, different machining processes are required for the flat and arc-shaped tops. For example, when using a conventional machine tool, machining the fiber optic connector mounting hole on the flat top can be considered as machining an angled hole on a flat plate. When machining an angled hole on a flat plate, because the center of the hole is not perpendicular to the drilling plane, the drill bit experiences uneven force, making it difficult to guarantee the perpendicularity requirement of the drilling. Therefore, it is necessary to add a step of creating a conical pit on the drilling plane to the original drilling process.

[0046] For the top of the flat or arc-shaped fiber optic mounting base 2, a five-axis machining center can be used to drill angled holes when machining fiber optic connector mounting holes. Compared to ordinary machine tools, a five-axis machining center can better ensure the machining accuracy of the fiber optic connector mounting holes and the positional accuracy between multiple holes, while also having higher machining efficiency.

[0047] like Figure 2 As shown, the fiber optic connector mounting hole has a central mounting hole, the centerline of which is perpendicular to the horizontal line in the incident plane. This central mounting hole facilitates the installation of the incident fiber as a calibration fiber for the motor-driven shaft rotation. To obtain horizontal emitted light, the incident angle of the light is 45 degrees, that is, the angle between the reflecting surface of the mirror and the horizontal plane is 45 degrees, which facilitates the measurement and verification of the rotation angle of the motor-driven shaft.

[0048] Furthermore, in one embodiment, the frame includes an upper frame 5 and support feet 6, with a pair of support feet 6 fixedly installed at both ends of the bottom of the upper frame 5; the upper frame 5 is a hollow structure, and the optical fiber fixing seat 2 is fixedly installed in the upper frame 5.

[0049] Preferably, the support foot 6 is also provided with weight-reducing holes to reduce the overall weight of the frame.

[0050] Furthermore, in one embodiment, the switching device further includes an intelligent driving unit 11 and a motor 12; the motor 12 is fixedly mounted on one side of one of the support feet 6, the intelligent driving unit 11 is mounted between a pair of support feet 6 and located below the fiber optic mounting base 2, and the reflector assembly 10 is mounted on the slider of the intelligent driving unit 11 via a reflector mount 9; the output shaft of the motor 12 drives the stator of the intelligent driving unit 11 to rotate, and the rotor of the intelligent driving unit 11 drives the slider to move, thereby driving the reflector assembly 10 to move in a direction perpendicular to the incident plane, so that different types of fiber optic outgoing light are reflected by reflectors at different angles and then emitted horizontally, realizing fiber optic switching. When all reflector assemblies are removed, the input light of the folding-axis telescope is directly incident on the Tip / Tilt.

[0051] Here, switching between different fiber optic light sources is accomplished solely through the one-dimensional rotation of the motor's output shaft, avoiding the need for high-precision position switching for each target fiber optic light source and reducing the difficulty of switching.

[0052] Here, the switching device can be replaced with the following scheme: The switching device includes a rotating shaft, a mirror chamber, a reflector, and a motor. The motor drives the rotating shaft to rotate, which in turn rotates the reflector inside the mirror chamber, making the normal of the reflector's reflecting surface the angle bisector. The incident light is reflected by the reflector to form a horizontal outgoing light. By switching the normal as the angle bisector of different angles, the switching of the incident fiber is achieved. This method completes the switching of different fiber optic light sources solely through the one-dimensional rotation of the motor's output shaft, avoiding high-precision position switching for each target fiber optic light source and reducing the switching difficulty.

[0053] Furthermore, in one embodiment, the adjustment device includes an adjusting screw 3 and a leaf spring 4. A pair of leaf springs 4 are respectively installed on both sides of the optical fiber holder 2 and connected to the upper frame 5, and are respectively located on both sides of the incident plane. The compression direction of the leaf springs 4 is perpendicular to the incident plane. A pair of pressure plates are provided on the upper frame 5, respectively located above the pair of leaf springs 4. The tail end of the adjusting screw 3 passes through the threaded hole on the pressure plate and abuts against the leaf spring 4. By adjusting the adjusting screw 3, the leaf spring 4 deforms and generates elastic force applied to the optical fiber holder 2, pushing the position of the optical fiber holder 2 to move, thereby realizing the adjustment of the position of the incident optical fiber.

[0054] Here, leaf spring 4 can be either an arc-shaped leaf spring or a steel leaf spring. When using a steel leaf spring, prestress is applied to it to create a bend, leaving an adjustment margin.

[0055] Furthermore, in one embodiment, the adjustment device further includes a set wire structure for fine-tuning the position of the optical fiber holder; the set wire structure includes a pair of set wires, one end of which is respectively installed on two sides of the upper frame 5 parallel to the incident plane, and the other end abuts against the adjustment side of the optical fiber holder 2, the adjustment side being parallel to the incident plane; by adjusting the set wires on both sides of the upper frame 5, the optical fiber holder 2 is moved horizontally along a direction perpendicular to the incident plane, thereby achieving fine-tuning of the position of the incident optical fiber.

[0056] Furthermore, in one embodiment, a guide groove is provided on the side wall of the upper frame 5, the fixed end of the optical fiber fixing seat 2 is placed in the guide groove, the side wall of the guide groove positions the fixed end, and the optical fiber fixing seat 2 can slide along the guide groove; a first slot is provided on the inner side wall of the upper frame 5 parallel to the incident plane, and a second slot is provided on the side wall of the optical fiber fixing seat 2 located on both sides of the incident plane, and the two ends of the leaf spring 4 are respectively engaged in the first slot and the second slot.

[0057] Furthermore, in one embodiment, the precision calibration device includes a Tip / Tilt reflector 7 and a Tip / Tilt actuator 8; the Tip / Tilt reflector 7 is used to reflect the reflected light from the reflector group into the terminal instrument; the Tip / Tilt actuator 8 is used to correct the switching error of the switching device and the error caused by other noise loads based on the feedback error result of the camera inside the terminal instrument, so that the reflected light from the reflector group accurately enters the terminal instrument.

[0058] More preferably, the outer surfaces of the frame, fiber optic mount, switching device, and adjustment device are all coated with a black coating, which helps to reduce the impact of stray light on the performance of terminal instruments or related testing equipment.

[0059] More preferably, the surface of the output end of the incident optical fiber 1 is uniformly coated with refractive index oil to ensure that the maximum transmission efficiency is obtained after the incident optical fiber is connected.

[0060] More preferably, the motor 12 can be an encoder motor. The output shaft of the encoder motor has a zero position and a switching position. When the output shaft is in the zero position, the incident light emitted from the incident optical fiber installed in the central mounting hole is reflected by the reflector to form a horizontal outgoing light. When the output shaft is in the switching position, the normal of the reflecting surface of the reflector coincides with the angle bisector of the included angle. Using an encoder motor is beneficial for implementing high-precision closed-loop control and further improving the imaging position accuracy of the incident optical fiber.

[0061] More preferably, the monitoring CCD and Tip / Tilt8 installed in the terminal instrument form a closed-loop control to precisely correct the orientation of the incident light.

[0062] In one embodiment, a method for multi-channel switching of an astronomical terminal instrument is provided, the method comprising the following steps:

[0063] Step 1: Calibrate the zero position and switching position of the encoder motor's output shaft, and obtain the step value of each switching position relative to the zero position;

[0064] Step 2: Adjust the output shaft of the encoder motor to the zero position;

[0065] Step 3: Switch to different step values ​​to introduce the incident light from different optical fibers into the terminal instrument.

[0066] Furthermore, in one embodiment, in order to implement high-precision closed-loop control of the position of the incident optical fiber, the method further includes:

[0067] Step 4: The monitoring CCD installed in the terminal instrument images the incident light and performs image processing. The monitoring CCD feeds back the incident error value of the image to the Tip / Tilt control system to correct the orientation of the incident light.

[0068] This method enables fully automatic switching of incident optical fibers, improving switching efficiency and accuracy, while avoiding the impact on equipment performance caused by manual switching requiring entry into the equipment site.

[0069] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention without departing from its spirit and scope should be included within the protection scope of the present invention.

Claims

1. A multi-channel switching device for astronomical terminal instruments, characterized by, The device includes a frame, an optical fiber mount, a switching device, an adjustment device, and a precision calibration device. The fiber optic mounting base is fixedly installed on the upper end of the frame. Multiple optical fibers are arranged on the fiber optic mounting base, and the outgoing light rays of the optical fibers are in the same incident plane. The switching device is installed at the lower end of the frame and below the fiber optic mounting base. It includes a reflector group and is used to switch between different types of optical fibers, thereby allowing the light emitted from different types of optical fibers to enter the terminal instrument. The adjustment device is used to adjust the position of the optical fiber holder in a direction perpendicular to the incident plane; The precision calibration device is used to allow the optical fiber output light to enter the terminal instrument, and at the same time, it is used to correct the switching error of the switching device and the error caused by other noise loads based on the error feedback result of the camera inside the terminal instrument. The reflector group includes reflectors at different angles, and the outgoing light from different types of optical fibers corresponds to reflectors at different angles. After being reflected by the reflectors, the outgoing light from the optical fibers forms a horizontal outgoing light beam that is incident on the precision calibration device. After being calibrated and reflected by the precision calibration device, it enters the terminal instrument. The switching device also includes an execution unit and a motor; the motor is fixedly installed on one side of one of the support feet, the execution unit is installed between a pair of support feet and below the fiber optic mounting base, and the reflector assembly is installed on the slider of the execution unit; the output shaft of the motor drives the stator of the execution unit to rotate, and the rotor of the execution unit drives the slider to move, thereby driving the reflector assembly to move in a direction perpendicular to the incident plane, so that different types of fiber optic light are reflected by reflectors at different angles and then emitted horizontally, realizing fiber optic switching; The adjustment device includes an adjusting screw and leaf springs. A pair of leaf springs are respectively installed on both sides of the fiber optic mounting base and connected to the upper frame, and are respectively located on both sides of the incident plane. The compression direction of the leaf springs is perpendicular to the incident plane. A pair of pressure plates are provided on the upper frame, respectively located above the pair of leaf springs. The tail end of the adjusting screw passes through the threaded hole on the pressure plate and abuts against the leaf spring. By adjusting the adjusting screw, the leaf spring is deformed to generate elastic force applied to the fiber optic mounting base, pushing the position of the fiber optic mounting base to move, thereby realizing the adjustment of the position of the incident fiber. The adjustment device also includes a set wire structure for fine-tuning the position of the fiber optic fixture. The set wire structure includes a pair of set wires, one end of which is installed on two sides of the upper frame parallel to the incident plane, and the other end of which abuts against the adjustment side of the fiber optic fixture, which is parallel to the incident plane. By adjusting the set wires on both sides of the upper frame, the fiber optic fixture can be moved horizontally in a direction perpendicular to the incident plane, thereby achieving fine-tuning of the position of the incident fiber.

2. The multi-channel switching device for astronomical terminal instruments according to claim 1, characterized in that, The frame includes an upper frame and support feet, with a pair of support feet fixedly installed at both ends of the bottom of the upper frame; the upper frame is a hollow structure, and the fiber optic mounting base is fixedly installed in the upper frame.

3. The multi-channel switching device for astronomical terminal instruments according to claim 1, characterized in that, A guide groove is provided on the side wall of the upper frame, and the fixed end of the optical fiber fixing seat is placed in the guide groove. The side wall of the guide groove positions the fixed end, and the optical fiber fixing seat can slide along the guide groove. A first slot is provided on the inner side wall of the upper frame parallel to the incident plane, and a second slot is provided on the side wall of the optical fiber fixing seat located on both sides of the incident plane. The two ends of the leaf spring are respectively engaged in the first slot and the second slot.

4. The multi-channel switching device for astronomical terminal instruments according to claim 1, characterized in that, The precision calibration device includes a Tip / Tilt reflector and a Tip / Tilt actuator; the Tip / Tilt reflector is used to reflect the reflected light from the reflector group into the terminal instrument; The Tip / Tilt actuator is used to correct the switching error of the switching device and the error caused by other noise loads based on the feedback error result of the camera inside the terminal instrument, so that the reflected light from the mirror group accurately enters the terminal instrument.

5. The multi-channel switching device for astronomical terminal instruments according to claim 1, characterized in that, The motor is an encoder motor, and the output shaft of the encoder motor has a zero position and a switching position, which accurately calibrates the switching position of different incident optical fibers corresponding to different positions. When the output shaft is in the zero position, the outgoing light of the optical fiber installed in the center position is reflected by the reflector to form a horizontal outgoing light. When the output shaft is in the switching position, the normal of the reflecting surface of the reflector coincides with the angle bisector of the included angle. The included angle is the angle formed by the outgoing light of the optical fiber and the horizontal line in the incident plane.

6. A method for switching a plurality of channels of an astronomical terminal instrument based on the apparatus according to any one of claims 1 to 5, characterized by, The method includes the following steps: Step 1: Calibrate the zero position and switching position of the encoder motor's output shaft, and obtain the step value of each switching position relative to the zero position; Step 2: Adjust the output shaft of the encoder motor to the zero position; Step 3: Switch to different step values ​​to introduce the incident light from different optical fibers into the terminal instrument.

7. The astronomical terminal instrument multi-channel switching method according to claim 6, characterized in that, The method also includes: Step 4: The monitoring CCD installed in the terminal instrument images the incident light and performs image processing. The monitoring CCD feeds back the incident error value of the image to the Tip / Tilt control system to correct the orientation of the incident light.

Images