A high-precision, portable laser terminal optical calibration device and method

Abstract

The present invention discloses a high-precision, portable laser terminal optical calibration device and method. The device includes an off-axis telescope primary mirror assembly, an off-axis telescope secondary mirror assembly, a first folding mirror assembly, a first beam splitter assembly, a second beam splitter assembly, a beam receiving assembly, a multi-spectral detector, a beam emitting assembly, an optical fiber assembly, a movable folding mirror assembly, a self-calibration mirror assembly, a movable beam collector assembly, a first beam collector assembly, a second beam collector assembly, and a main structure. The optical axes of the beam receiving assembly and the beam emitting assembly are perpendicular to each other. The normal directions of the first folding mirror assembly, the first beam splitter assembly, the second beam splitter assembly, and the movable folding mirror assembly all form a 45° angle with the zero field of view optical axis. The present invention meets the ground calibration requirements for the parallelism, emission efficiency, and divergence angle of multiple optical axes of transmission / reception of laser communication terminals with an aperture of less than 50 mm and an operating wavelength of 800 nm and 1550 nm. It has high optical transmission and reception isolation and strong practicality.

Description

Technical Field

[0001] The present invention relates to a laser communication optical calibration device and method, which can meet the test requirements of 800nm ​​and 1550nm laser beam emission and receiving optical axis parallelism, emission angle and optical efficiency, especially indoor and outdoor close-range testing, and belongs to the field of laser communication. Background Art

[0002] As the amount of global information data continues to increase, users are bound to have higher and higher demands for data transmission capabilities. Laser communication systems have obvious advantages over microwave communications, including fast data transmission, low energy loss, large bandwidth, small payload size, anti-interference, and good confidentiality. Laser communication systems usually have the functions of beacon, signal transmission, and beacon, signal reception, requiring optical calibration devices to have the same functions. The optical integrated test platform in the laboratory is usually composed of large coaxial parallel light pipes, large-aperture plane reflectors, beam splitters, folding mirrors, collimating or converging lenses, multiple lasers of different bands, multiple detectors of different bands, etc. The devices are separated from each other and take up a large space. They are used to calibrate the optical and electrical indicators of laser terminals in the laboratory, but cannot meet the requirements of outdoor laser docking.

[0003] In order to meet the outdoor docking requirements of the laser communication system, while ensuring the technical indicators of the optical device, it is necessary to optimize the structure of the optical device, reduce its weight, and facilitate the carrying of the optical device. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-precision, portable laser terminal optical calibration device and method to solve the problem that the existing technology cannot meet the requirements of outdoor laser docking.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A high-precision, portable laser terminal optical calibration device, comprising an off-axis telescope primary mirror assembly, an off-axis telescope secondary mirror assembly, a first folding mirror assembly, a first spectroscope assembly, a second spectroscope assembly, a light beam receiving assembly, a multi-spectral detector, a light beam emitting assembly, an optical fiber assembly, a movable folding mirror assembly, a self-calibration mirror assembly, a movable light beam collector assembly, a first light beam collector assembly, a second light beam collector assembly and a main structure; wherein the off-axis telescope primary mirror assembly and the off-axis telescope secondary mirror assembly constitute an off-axis two-reflecting telescope; the optical axes of the light beam receiving assembly and the light beam emitting assembly are perpendicular to each other; the normal directions of the first folding mirror assembly, the first spectroscope assembly, the second spectroscope assembly and the movable folding mirror assembly all form an angle of 45° with the zero field of view optical axis, and the self-calibration mirror assembly is located behind the first spectroscope assembly. end, and the normal direction is parallel to the zero field of view optical axis; the laser emits a fine light beam through the optical fiber component and the beam emitting component, and passes through the second beam splitter component, the first beam splitter component, the first folding mirror component, and the off-axis two-reflector telescope to emit a laser beam; the light beam emitted by the laser terminal to be measured passes through the off-axis two-reflector telescope, the first folding mirror component, the first beam splitter component, the second beam splitter component and the beam receiving component to converge the light beam and form an image on the multi-spectral detector; the movable folding mirror component is movably installed on the optical path between the second beam splitter component and the beam emitting component, the movable beam collector component is movably installed on the optical path between the first beam splitter component and the self-calibration mirror component, the first beam collector component is located on the rear optical path of the second beam splitter component, and the second beam collector component is located on the rear optical path of the first beam splitter component.

[0007] Furthermore, the off-axis telescope primary mirror assembly and the off-axis telescope secondary mirror assembly are both symmetrical parabolic mirrors.

[0008] Furthermore, the ratio of transmittance to reflectivity of the first spectroscope assembly and the second spectroscope assembly at 800 nm and 1550 nm is 10:90.

[0009] Furthermore, the light beam receiving component is a four-piece achromatic lens with an effective aperture of 8 mm, a field of view of 70 mrad, an entrance pupil distance of 110 mm, and a focal length of 70 mm.

[0010] Furthermore, the multi-spectral detector has a response wavelength range of 550 nm to 1700 nm.

[0011] Furthermore, the beam emitting assembly can emit Gaussian laser beams with wavelengths of 800 nm and 1550 nm, wherein the emission angle of the 1550 nm laser beam is 400 urad.

[0012] Furthermore, the light beam emitting component and the optical fiber component are connected in a standard FC / APC format.

[0013] Furthermore, the movable folding mirror assembly and the movable beam collector assembly are both moved by a one-dimensional guide rail.

[0014] Furthermore, the movable beam dump assembly, the first beam dump assembly and the second beam dump assembly are all hollow cubic structures, and two pieces of absorptive colored glass are arranged inside.

[0015] Furthermore, the apertures of the first folding mirror assembly, the movable folding mirror assembly, and the self-calibrating mirror assembly are 25 mm, the aperture of the first beam splitter assembly is 30 mm, and the aperture of the second beam splitter assembly is 50 mm.

[0016] On the other hand, the present invention also provides a method for calibrating the parallelism of a transmitting axis and a receiving axis using an interferometer, comprising the following steps:

[0017] Step 1: Remove the beam emitting assembly from the above-mentioned high-precision, portable laser terminal optical calibration device, and place an interferometer in the position of the beam emitting assembly. The interferometer emits a parallel beam that is reflected into the interferometer through a spectroscopic system composed of a second spectroscope assembly and a first spectroscope assembly and a self-calibration mirror assembly, thereby forming interference fringes with the reference light inside the interferometer. The interferometer is adjusted to minimize the tilt of the interference fringes.

[0018] Step 2: At this time, the other path of the interferometer's transmitted light beam passes through the second beam splitter assembly, the first beam splitter assembly, the self-calibration mirror assembly, and the beam receiving assembly, and is imaged at the target surface position of the multi-spectral detector. The center position of the light spot is determined by the sub-pixel centroid interpretation algorithm, and this position is used as the calibration zero point position;

[0019] Step 3, move the interferometer out, move the beam emitting assembly in, and then adjust the posture of the beam emitting assembly 8 so that the beam passes through the self-calibration mirror assembly to self-align until it reaches the calibrated zero position, completing the calibration of the parallelism of the emitting axis and the receiving axis.

[0020] In a third aspect, the present invention further provides a method for periodically self-calibrating the parallelism of the transmitting and receiving optical axes, comprising the following steps:

[0021] Step 1: After the calibration is completed using the above-mentioned method of calibrating the parallelism of the transmitting axis and the receiving axis using an interferometer, the movable beam collector assembly in the above-mentioned high-precision, portable laser terminal optical calibration device is regularly moved out of the optical path; the optical fiber assembly and the beam emitting assembly are connected to the laser and emit a light beam, the light beam passes through the second beam splitter assembly, the first beam splitter assembly, and then is reflected by the self-calibration mirror assembly, and is imaged onto the multi-spectral detector through the beam receiving assembly, and it is observed whether the imaging point on the multi-spectral detector deviates from the zero point position calibrated in the above-mentioned interferometer calibration method;

[0022] Step 2: If there is a deviation, the posture of the light beam emitting assembly is adjusted so that the light beam passes through the self-calibration mirror assembly and is self-calibrated until it reaches the zero point position mentioned above, thereby completing the self-calibration.

[0023] The advantages of the present invention compared with the prior art are:

[0024] (1) The present invention adopts a common optical path design for the receiving channel and the transmitting channel, and has the function of receiving and transmitting at 800nm ​​and 1550nm wavelengths, thereby avoiding the problems of large volume and poor optical axis parallelism caused by different apertures of the transmitting and receiving channels. In the laboratory, field and test field environment, the main optical index test requirements of the laser terminal with an effective aperture less than 50mm are quickly achieved; at the same time, the off-axis two-reflector telescope 16 and multiple beam collector components are used to improve the optical receiving and transmitting isolation of the present invention.

[0025] (2) The off-axis double-reflector telescope 16, the beam emitting assembly 8 and the beam receiving assembly 6 of the present invention have a small effective aperture, and all optical elements can be used as independent modules and integrated into a main structure. Compared with the optical system test platform in which each optical device is separated, the off-axis double-reflector telescope 16, the beam emitting assembly 8 and the beam receiving assembly 6 of the present invention have a compact structure, light weight, easy to carry and strong practicality.

[0026] (3) The transmitting system of the present invention adopts an off-axis double-reflecting telescope 16, which allows multiple wavelengths of light beams to be transmitted without being affected by chromatic aberration, thereby improving the practicality of the optical device.

[0027] (4) The present invention has a built-in self-calibration component consisting of a self-calibration mirror component 11 and a movable beam collector component 12, which can periodically self-calibrate the optical transmission and receiving optical axes of the optical system itself. During operation, the movable beam collector component 12 can be moved out of the optical path between the first beam splitter component 4 and the self-calibration mirror component 11.

[0028] (5) The present invention has a built-in movable folding mirror 10, which can introduce the light beam into the entrance of the spatial optical power meter and quickly test the optical efficiency of the laser terminal emission. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the optical path of the high-precision, portable laser terminal optical calibration device of the present invention;

[0030] Figure 2 This is a schematic structural diagram of the high-precision, portable laser terminal optical calibration device of the present invention;

[0031] Figure 3 This is a schematic diagram of the connection between the high-precision, portable laser terminal optical calibration device and the two-dimensional turntable coarse alignment structure of the present invention;

[0032] Figure 4 This is a schematic diagram of the optical path of the light-transmitting and light-receiving axis using an interferometer according to the present invention;

[0033] Figure 5 This is a schematic diagram of the self-calibration of the light-receiving and light-emitting axis of the present invention. DETAILED DESCRIPTION

[0034] like Figure 1 As shown, the present invention provides a high-precision, portable laser terminal optical calibration device, including an off-axis telescope primary mirror assembly 1, an off-axis telescope secondary mirror assembly 2, a first folding mirror assembly 3, a first beam splitter assembly 4, a second beam splitter assembly 5, a beam receiving assembly 6, a multi-spectral detector 7, a beam emitting assembly 8, an optical fiber assembly 9, a movable folding mirror assembly 10, a self-calibration mirror assembly 11, a movable beam collector assembly 12, a first beam collector assembly 13, a second beam collector assembly 14 and a main structure 15. Among them, the off-axis telescope primary mirror assembly 1 and the off-axis telescope secondary mirror assembly 2 form an off-axis two-reflecting telescope 16; the optical axes of the light beam receiving assembly 6 and the light beam emitting assembly 8 are perpendicular to each other; the normal directions of the first folding mirror assembly 3, the first beam splitter assembly 4, the second beam splitter assembly 5, and the movable folding mirror assembly 10 are all at an angle of 45° to the zero field of view optical axis, and the self-calibration mirror assembly 11 is located at the rear end of the first beam splitter assembly 4, and the normal direction is parallel to the zero field of view optical axis; the laser emits a fine light beam through the optical fiber assembly 9 and the light beam emitting assembly 8, passes through the second beam splitter assembly 5, the first beam splitter assembly 4, the first folding mirror assembly 3, and the off-axis two-reflecting telescope 16 to emit laser light beam; similarly, the light beam emitted by the laser terminal to be measured passes through the off-axis two-reflective telescope 16, the first folding mirror assembly 3, the first spectroscope assembly 4, the second spectroscope assembly 5 and the light beam receiving assembly 6 to converge the light beam and image it on the multi-spectral detector 7; the movable folding mirror assembly 10 is movably mounted on the optical path between the second spectroscope assembly 5 and the light beam emitting assembly 8, the movable beam collector assembly 12 is movably mounted on the optical path between the first spectroscope assembly 4 and the self-calibration mirror assembly 11, the first beam collector assembly 13 is located on the rear end optical path of the second spectroscope assembly 5, and the second beam collector assembly 14 is located on the rear end optical path of the first spectroscope assembly 4.

[0035] like Figure 1 、 2 As shown, the present invention uses an off-axis double-reflector telescope 16 as a common-channel signal transmission / reception device. The off-axis double-reflector telescope 16 comprises an off-axis telescope primary mirror assembly 1 and an off-axis telescope secondary mirror assembly 2. The off-axis telescope 16 has an effective aperture of 50 mm, a mirror spacing of 100 mm, a magnification of -7, a transmission efficiency exceeding 99.5%, and a central field wavefront aberration of less than 15 nm. The off-axis telescope primary mirror assembly 1 is a parabolic mirror with a focal length of 87.5 mm and a 50 mm offset pupil. The off-axis telescope secondary mirror assembly 2 is a symmetrical parabolic mirror with a focal length of 12.5 mm.

[0036] The ratio of transmittance to reflectance of the first beam splitter assembly 4 and the second beam splitter assembly 5 at 800 nm and 1550 nm is 10:90.

[0037] The beam receiving component 6 is a four-piece achromatic lens with an effective aperture of 8mm, a field of view of 70mrad, an entrance pupil distance of 110mm, a focal length of 70mm, and a central field wave order difference of better than 30nm for wavelengths of 632.8nm, 800nm ​​and 1550nm.

[0038] The multispectral detector 7 has a response wavelength range of 550nm~1700nm. The specifications of the multispectral detector 7 are: effective target surface 1 / 1.8 inches, response spectrum range 500nm~1700nm, camera array 1600×1200, pixel size dx or dy is 4.5um, then the spatial resolution θ corresponding to a single pixel, and The use of a sub-pixel subdivision algorithm can improve the accuracy of spot centroid interpretation to better than 1urad. The beam receiving component 6 and the multispectral detector 7 are designed as a modular whole, and the electrical interface of the multispectral detector 7 is pluggable.

[0039] The beam emitting assembly 8 uses a parabolic reflector to achieve beam collimation, with an effective aperture of 6.5mm and a focal length of 25mm. The beam emitting assembly 8 can emit Gaussian laser beams with wavelengths of 800nm ​​and 1550nm, of which the 1550nm laser beam has an emission angle of 400urad.

[0040] like Figure 2 As shown, the 800nm ​​and 1550nm wavelengths of the present invention share a light beam emitting component 8, and a wavelength division multiplexer is used to couple the light beams of the two optical fibers into the optical fiber component 9, and the light beams are emitted through the light beam emitting component 8. The interface of the optical fiber adopts a standard FC / APC connection form, and the optical cable can be plugged in and out, which is easy to carry. The present invention meets the multi-wavelength test conditions of the laser terminal, and has only one emission branch, which optimizes the structure and reduces the weight. The light beam emitting component 8 and the optical fiber component 9 are connected in a standard FC / APC form.

[0041] The movable folding mirror assembly 10 is controlled by a one-dimensional guide rail and can be moved into or out of the optical path as needed to test the light transmission efficiency.

[0042] The movable beam dump assembly 12, the first beam dump assembly 13, and the second beam dump assembly 14 are all hollow cube structures, each containing two sheets of absorptive colored glass with a light absorption capacity exceeding 99.9%. The movable beam dump assembly 12 is controlled by a one-dimensional guide rail, allowing it to be moved into or out of the optical path as needed. The simultaneous installation of the movable beam dump assembly 12, the first beam dump assembly 13, and the second beam dump assembly 14 in the present invention effectively absorbs stray light in the optical path, improving the optical transmit / receive isolation of the device.

[0043] The apertures of the first folding mirror assembly 3, the movable folding mirror assembly 10, and the self-calibrating mirror assembly 11 are 25 mm, the aperture of the first beam splitter assembly 4 is 30 mm, and the aperture of the second beam splitter assembly 5 is 50 mm.

[0044] In summary, the device of the present invention utilizes a shared optical path design for both receiving and transmitting channels. The shared optical path includes an off-axis telescope primary mirror assembly 1, an off-axis telescope secondary mirror assembly 2, a first folding mirror assembly 3, a first beam splitter assembly 4, and a second beam splitter assembly 5. The receiving channel includes a signal receiving assembly 6 and a multispectral detector 7, while the receiving channel also includes a signal transmitting assembly 8 and an optical fiber assembly 9. The optical telescope has an effective aperture of 50 mm and an angular magnification of -7x. The transmitting and receiving lenses have small apertures, resulting in a clear structure and compact spatial arrangement. Compared to optical system test platforms that combine separate optical devices, the device is more miniaturized, modular, lightweight, and portable.

[0045] The above is the structural design of the high-precision, portable laser terminal optical calibration device of the present invention, and the method for testing it is described in detail below.

[0046] 1. During the optical index test of the laser terminal, the optical calibration device of the present invention can meet the close-range test requirements of the aperture less than 50mm, the parallelism of the receiving optical axis at wavelengths of 800nm ​​and 1550nm, the emission angle and the optical emission efficiency.

[0047] 1. Test the parallelism of the receiving optical axis.

[0048] like Figure 3 As shown, first, the device of the present invention is installed on the two-dimensional turntable 17, the optical fiber component 9 and the light beam emitting component 8 are connected to the 632.8nm laser and emit a red light beam, and the two-dimensional turntable 17 is adjusted until the emitted light beam covers the light input port of the laser terminal to be tested, completing the rough alignment, and then the laser terminal to be tested emits signal light, which can conveniently, quickly and accurately complete the establishment of the optical axis of the optical calibration device of the present invention and the laser terminal to be tested.

[0049] The laser terminal to be tested emits an 800nm ​​or 1550nm light beam, which is compressed by the off-axis two-reflector telescope 16 and then reflected multiple times by the first folding mirror assembly 3 and the first beam splitter assembly 4, and transmitted by the second beam splitter assembly 5 and the light beam receiving assembly 6. The light beam is converged and imaged on the multi-spectral detector 7. The center of mass position of the current light spot is quickly calculated according to the center of mass algorithm, and the zero position of the optical calibration device of the present invention is compared to test the deviation of multiple emission optical axes, that is, to test the parallelism of multiple optical axes. The optical calibration device of the present invention emits a 1550nm or 800nm ​​light beam to reach each receiving channel of the laser terminal to be tested. The parallelism of each receiving optical axis of the laser terminal to be tested can be calculated according to the calibration zero position of the laser terminal to be tested, and then the parallelism of the transmitting and receiving multiple optical axes of the laser terminal to be tested is calculated according to the coaxiality of the transmitting and receiving calibrated by the device of the present invention.

[0050] 2. Emission angle test.

[0051] According to the effective diameter d of the imaging spot (1 / e 2 ), the off-axis double-reflector telescope 16 has a magnification of -7, the focal length f of the signal receiving component 6 is 70mm, and the signal light emission angle of the laser terminal to be measured is .

[0052] 3. Optical emission efficiency test.

[0053] The laser terminal to be tested emits an 800nm ​​or 1550nm light beam, which is compressed by an off-axis two-reflector telescope 16 and then reflected multiple times by the first folding mirror assembly 3, the first beam splitter assembly 4, the second beam splitter assembly 5 and the movable folding mirror assembly 10, and the light beam is reflected into a large-aperture optical power meter, wherein the movable folding mirror assembly 10 is moved to the optical path between the second beam splitter assembly 5 and the second beam splitter assembly 8. According to the optical transmission efficiency of the optical calibration device of the present invention, the emission efficiency of the laser terminal to be tested can be calculated.

[0054] 2. A method for calibrating the parallelism of the transmitting axis and the receiving axis of the present invention using an interferometer.

[0055] The principle of this method is as follows Figure 4 As shown, the following steps are included:

[0056] Step 1: Remove the light beam emitting assembly 8 from the device of the present invention and place an interferometer in the position of the light beam emitting assembly 8. The interferometer emits a parallel light beam which is reflected into the interferometer through the optical splitting system composed of the second beam splitter assembly 5 and the first beam splitter assembly 4 and the self-calibration mirror assembly 11, thereby forming interference fringes with the reference light inside the interferometer. The interferometer is adjusted to minimize the tilt of the interference fringes.

[0057] Step 2: At this time, the other path of the interferometer-transmitted light beam passes through the second beam splitter assembly 5, the first beam splitter assembly 4, the self-calibration mirror assembly 11, and the beam receiving assembly 6, and is imaged at the target surface position of the multi-spectral detector 7. The center position of the light spot is determined by the sub-pixel centroid interpretation algorithm, and this position is used as the calibration zero point position;

[0058] Step 3, move the interferometer out, move the beam emitting assembly 8 in, and then adjust the posture of the beam emitting assembly 8 so that the light beam passes through the self-calibration mirror assembly 11 to self-align until it reaches the calibrated zero position, completing the calibration of the parallelism of the emitting axis and the receiving axis.

[0059] This method can be used to calculate the difference θ between the interferometer's transmitting optical axis and the interferometer's receiving optical axis. At this time, θ is also the parallelism deviation between the signal and receiving optical axes of the present invention, and its accuracy is ,in is the optical path difference caused by the optical axis deviation, To calibrate the beam diameter. Since the PV value test accuracy of the interferometer is generally better than 0.025 , so the optical axis parallelism of the interferometer after calibration is better than 1".

[0060] 3. Method for regular self-calibration of the parallelism of the transmitting and receiving optical axes

[0061] Since the transmitting component 8 and the optical fiber component 9 are not fixed with positioning pins, long-term use may cause posture changes, thereby causing the transmitting optical axis to deviate. This method is used for regular self-calibration of the optical axis. Figure 5 As shown, the following steps are included:

[0062] Step 1: Move the movable beam dump assembly 12 out of the optical path; connect the optical fiber assembly 9 and the beam emitting assembly 8 to the laser and emit a light beam. The light beam passes through the second beam splitter assembly 5, the first beam splitter assembly 4, and then is reflected by the self-calibration mirror assembly 11. The light beam is imaged onto the multispectral detector 7 through the beam receiving assembly 6. Observe whether the imaged point on the multispectral detector 7 deviates from the zero point position calibrated in the above-mentioned interferometer calibration method.

[0063] Step 2: If there is a deviation, adjust the posture of the light beam emitting component 8 so that the light beam passes through the self-calibration mirror component 11 and is self-calibrated until it reaches the zero point position mentioned above, completing the self-calibration.

[0064] Parts not described in detail in the description of the present invention belong to common knowledge among those skilled in the art.

Claims

1. A high-precision, portable laser terminal optical calibration device, characterized in that: The invention comprises an off-axis telescope primary mirror assembly (1), an off-axis telescope secondary mirror assembly (2), a first folding mirror assembly (3), a first beam splitter assembly (4), a second beam splitter assembly (5), a beam receiving assembly (6), a multi-spectral detector (7), a beam emitting assembly (8), an optical fiber assembly (9), a movable folding mirror assembly (10), a self-calibrating mirror assembly (11), a movable beam collector assembly (12), a first beam collector assembly (13), a second beam collector assembly (14) and a main structure ( 15); wherein the off-axis telescope primary mirror assembly (1) and the off-axis telescope secondary mirror assembly (2) form an off-axis two-mirror telescope (16); the optical axes of the light beam receiving assembly (6) and the light beam emitting assembly (8) are perpendicular to each other; the normal directions of the first folding mirror assembly (3), the first beam splitter assembly (4), the second beam splitter assembly (5), and the movable folding mirror assembly (10) are all at an angle of 45° to the zero field of view optical axis, the self-calibrating mirror assembly (11) is located at the rear end of the first beam splitter assembly (4), and The normal direction is parallel to the zero field of view optical axis; the laser emits a fine light beam through the optical fiber component (9) and the beam emitting component (8), and then passes through the second beam splitter component (5), the first beam splitter component (4), the first folding mirror component (3), and the off-axis two-reflector telescope (16) to emit a laser beam; the light beam emitted by the laser terminal to be measured passes through the off-axis two-reflector telescope (16), the first folding mirror component (3), the first beam splitter component (4), the second beam splitter component (5), and the beam receiving component (6) to converge the light beam and form an image on On the multi-spectral detector (7); the movable folding mirror assembly (10) is movably mounted on the optical path between the second beam splitter assembly (5) and the light beam emitting assembly (8); the movable beam collector assembly (12) is movably mounted on the optical path between the first beam splitter assembly (4) and the self-calibration mirror assembly (11); the first beam collector assembly (13) is located on the rear optical path of the second beam splitter assembly (5); and the second beam collector assembly (14) is located on the rear optical path of the first beam splitter assembly (4); The ratio of transmittance to reflectance of the first beam splitter assembly (4) and the second beam splitter assembly (5) at 800 nm and 1550 nm is 10:90; The beam emitting assembly (8) can emit Gaussian laser beams with wavelengths of 800 nm and 1550 nm, wherein the emission angle of the 1550 nm laser beam is 400 urad.

2. The high-precision, portable laser terminal optical calibration device according to claim 1, characterized in that: The off-axis telescope primary mirror assembly (1) and the off-axis telescope secondary mirror assembly (2) are both symmetrical parabolic mirrors.

3. The high-precision, portable laser terminal optical calibration device according to claim 1, characterized in that: The light beam receiving component (6) is a four-piece achromatic lens with an effective aperture of 8 mm, a field of view of 70 mrad, an entrance pupil distance of 110 mm, and a focal length of 70 mm.

4. The high-precision, portable laser terminal optical calibration device according to claim 1, characterized in that: The multi-spectral detector (7) has a response wavelength range of 550 nm to 1700 nm.

5. The high-precision, portable laser terminal optical calibration device according to claim 1, characterized in that: The light beam emission component (8) and the optical fiber component (9) are connected in a standard FC / APC format.

6. The high-precision, portable laser terminal optical calibration device according to claim 1, characterized in that: The movable folding mirror assembly (10) and the movable light beam collector assembly (12) are both moved via a one-dimensional guide rail.

7. The high-precision, portable laser terminal optical calibration device according to claim 1, characterized in that: The movable light beam collector component (12), the first light beam collector component (13) and the second light beam collector component (14) are all cube hollow structures, and two pieces of absorption-type colored glass are arranged inside.

8. The high-precision, portable laser terminal optical calibration device according to claim 1, characterized in that: The apertures of the first folding mirror assembly (3), the movable folding mirror assembly (10), and the self-calibrating mirror assembly (11) are 25 mm, the aperture of the first beam splitter assembly (4) is 30 mm, and the aperture of the second beam splitter assembly (5) is 50 mm.

9. A method for calibrating the parallelism of a transmitting axis and a receiving axis using an interferometer, characterized in that: The steps include: Step 1, remove the light beam emitting assembly (8) in the high-precision, portable laser terminal optical calibration device according to any one of claims 1 to 8, place an interferometer at the position of the light beam emitting assembly (8), and the interferometer emits a parallel light beam which is reflected into the interferometer through a spectroscopic system composed of a second spectroscope assembly (5) and a first spectroscope assembly (4) and a self-calibration mirror assembly (11), and forms interference fringes with the reference light inside the interferometer; adjust the posture of the interferometer so that the inclination of the interference fringes is minimized; Step 2, at this time, the other path of the interferometer-transmitted light beam passes through the second beam splitter assembly (5), the first beam splitter assembly (4), the self-calibration mirror assembly (11), and the light beam receiving assembly (6), and is imaged at the target surface position of the multi-spectral detector (7). The center position of the light spot is determined by a sub-pixel centroid interpretation algorithm, and this position is used as the zero point position of the calibration; Step 3, move the interferometer out, move the beam emitting assembly (8) in, and then adjust the posture of the beam emitting assembly (8) so that the beam passes through the self-calibration mirror assembly (11) to calibrate to the calibrated zero point position, completing the calibration of the parallelism of the emitting axis and the receiving axis.

10. A method for periodically self-calibrating the parallelism of the transmitting and receiving optical axes, characterized in that: The steps include: Step 1, after the calibration is completed by the method of using an interferometer to calibrate the parallelism of the transmitting axis and the receiving axis as described in claim 9, the movable beam collector assembly (12) in the high-precision, portable laser terminal optical calibration device as described in any one of claims 1 to 8 is regularly moved out of the optical path; the optical fiber assembly (9) and the beam emitting assembly (8) are connected to the laser and emit a light beam, the light beam passes through the second beam splitter assembly (5), the first beam splitter assembly (4) and then is reflected by the self-calibration mirror assembly (11), and is imaged onto the multi-spectral detector (7) through the beam receiving assembly (6), and whether the imaging point on the multi-spectral detector (7) deviates from the zero point position calibrated in the method of using an interferometer to calibrate the parallelism of the transmitting axis and the receiving axis as described in claim 9; Step 2: If there is a deviation, the posture of the light beam emitting assembly (8) is adjusted so that the light beam passes through the self-calibration mirror assembly (11) and is self-calibrated until it reaches the zero point position, thereby completing the self-calibration.

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