Laser radar light emitting position calibration system

Abstract

The invention relates to the technical field of radar testing, and discloses a laser radar light emitting position calibration system which comprises a first collimation unit, a visible light output unit and an optical beam combining unit. The first collimation unit is used for collimating a radar laser beam output by a to-be-measured laser radar and inputting the collimated radar laser beam into the optical beam combining unit, and the radar laser beam is invisible light; the visible light output unit is used for generating a visible light beam and outputting the visible light beam to the optical beam combining unit; and the optical beam combining unit is used for changing the emitting direction of the visible light beam, so that the visible light beam and the radar laser beam are collimated and coaxially emitted. According to the invention, the equipment cost of laser radar alignment debugging can be reduced.

Description

Technical Field

[0001] The present invention relates to the field of radar testing technology, and in particular to a laser radar light output position calibration system. Background Art

[0002] With the rapid development of science and technology, LiDAR has become a powerful detection tool and is widely used in the fields of atmosphere, meteorology, environment, space, remote sensing and military. LiDAR is a detection technology that actively sends and receives lasers. In terms of laser wavelength selection, LiDAR generally selects infrared laser light sources with invisible wavelengths for the sake of anti-sunlight interference and eye safety. At the same time, in some special test occasions, it is necessary to test the distance, vibration and speed of small targets. In order to save costs, it is generally not necessary to use array LiDAR for testing. Single-point LiDAR can meet this test requirement.

[0003] At present, when invisible light single-point laser radar is detecting targets, it is necessary to confirm whether the laser radar is aligned with the target, that is, to confirm whether the laser is directly irradiating the target. However, since the laser radar light source is invisible light, the human eye cannot directly confirm whether the laser is irradiating the target. Using infrared color display cards or infrared cameras to confirm the laser irradiation position will increase the equipment cost.

[0004] Therefore, a low-cost lidar calibration solution is urgently needed. Summary of the invention

[0005] In view of this, the present invention provides a laser radar light output position calibration system to solve or partially solve the technical problem of high cost of existing laser radar illumination position confirmation solutions.

[0006] The technical solution proposed by the present invention is as follows:

[0007] The present invention provides a laser radar light output position calibration system, comprising a first collimation unit, a visible light output unit and an optical beam combining unit; the first collimation unit is used to collimate a radar laser beam output by a laser radar to be tested, and input the collimated radar laser beam into the optical beam combining unit, wherein the radar laser beam is invisible light; the visible light output unit is used to generate a visible light beam, and output the visible light beam to the optical beam combining unit; the optical beam combining unit is used to change the emission direction of the visible light beam, so that the visible light beam and the radar laser beam are collimated and emitted coaxially.

[0008] The laser radar light output position calibration system of the embodiment of the present invention collimates and coaxially emits the radar laser beam collimated by the first collimation unit and the visible light beam output by the visible light output unit through an optical beam combining unit, so that the optical path of the visible light beam is the same as the optical path of the radar laser beam output by the laser radar to be tested. Therefore, the position of the radar laser beam irradiated on the target object can be determined by observing the position of the visible light beam. The irradiation position of the laser radar output light can be quickly confirmed without the aid of an external infrared color display card or an infrared camera, thereby improving the efficiency of the laser radar in aligning the target object and reducing the time cost and equipment cost of the laser radar alignment and debugging.

[0009] Optionally, the optical beam combining unit includes a dichroic mirror and a second collimating unit; the dichroic mirror is used to transmit the collimated radar laser beam to the optical beam combining unit, and reflect the visible light beam to the optical beam combining unit to change the emission direction of the visible light beam so that the visible light beam and the radar laser beam are emitted coaxially; the second collimating unit is used to collimate the visible light beam and the radar laser beam.

[0010] In this method, the characteristics of the dichroic mirror are utilized to achieve coaxial emission of light beams of different wavelengths (radar laser beam and visible light beam), and the collimation of the visible light beam and the radar laser beam is further ensured by the second collimation unit to enhance the overlap effect of the light beams after emission.

[0011] Optionally, the second collimating unit includes a focusing lens and a second collimating lens; the focusing lens is used to focus the radar laser beam at a first focal position of the second collimating lens corresponding to the wavelength of the radar laser beam, and to image the visible light beam at a second focal position of the second collimating lens corresponding to the wavelength of the visible light beam; the second collimating lens is used to collimate the visible light beam and the radar laser beam for output.

[0012] In this method, by using a focusing lens and a second collimating lens in combination, light beams of different wavelengths are imaged at their respective focal positions and then collimated to emit, thereby avoiding the problem of poor light beam overlap caused by positional chromatic aberration of the second collimating lens, thereby improving the optical performance and calibration accuracy of the system.

[0013] Optionally, the visible light output unit includes a visible light source and an imaging lens; the visible light source is used to generate and output the visible light beam; and the imaging lens is used to image the visible light beam output by the visible light source onto the dichroic mirror.

[0014] In this method, a visible light source is used to generate a visible light beam, which improves the stability of the light source and the quality of the light beam. The visible light beam is accurately imaged on a dichroic mirror through an imaging lens, further ensuring the coaxiality of the light beam and the accuracy of calibration.

[0015] Optionally, the emitting direction of the radar laser beam output by the laser radar to be tested is perpendicular to the emitting direction of the visible light beam output by the visible light output unit, and the emitting directions of the visible light beam output by the dichroic mirror and the visible light beam output by the visible light output unit are at 45°.

[0016] In this method, the direction of the visible light beam is changed by setting the angle of the dichroic mirror to ensure that the radar laser beam and the visible light beam are emitted coaxially.

[0017] Optionally, the positions of the focusing lens and the second collimating lens satisfy the following relationship:

[0018] D1=a+b

[0019]

[0020] In the formula, D1 is the distance between the focusing lens and the second collimating lens, D2 is the distance between the focusing lens and the dichroic mirror, a is the focal length of the second collimating lens corresponding to the wavelength of the radar laser beam, b is the focal length of the second collimating lens corresponding to the wavelength of the visible light beam, and c is the focal length of the focusing lens corresponding to the wavelength of the visible light beam.

[0021] In this manner, the positions of the focusing lens and the second collimating lens are adjusted so that both the radar laser beam and the visible light beam can be located at their respective collimation focal points, thereby improving the beam overlap effect.

[0022] Optionally, the visible light source is a semiconductor laser.

[0023] Semiconductor lasers have the advantages of small size, low energy consumption and long life, which improves the portability and economy of the system.

[0024] Optionally, the first collimating unit includes a first collimating lens, and the radar laser beam output by the laser radar to be tested is collimated by the first collimating lens and then input into the optical beam combining unit.

[0025] In this method, the radar laser beam is collimated by the first collimating lens, the emission angle of the radar laser beam is reduced, and the radar laser beam is collimated, so that it can be ensured that the laser energy irradiated on the target object can meet the test requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly express the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 A schematic diagram of an optical path of a laser radar light output position calibration system according to an embodiment of the present invention;

[0028] Figure 2 Another optical path schematic diagram of the laser radar light output position calibration system in an embodiment of the present invention;

[0029] Figure 3 Schematic diagram of the optical path of lens chromatic aberration phenomenon in an embodiment of the present invention.

[0030] Reference numerals:

[0031] 100-first collimating unit; 200-optical beam combining unit; 300-visible light output unit; 1-radar laser light source; 2-first collimating lens; 3-dichroic mirror; 4-focusing lens; 5-second collimating lens; 6-visible light source; 7-imaging lens. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can also be the internal connection of two components, it can be a wireless connection, or it can be a wired connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] An embodiment of the present invention provides a laser radar light output position calibration system suitable for determining the position of a laser radar, especially a single-point laser radar, emitting a light beam.

[0037] At present, the laser emission scheme of a single-point laser radar generally includes two parts: a laser light source and a collimating lens. The laser light source is used to provide laser signals, and generally uses a semiconductor laser. Its light output is generally a radar laser beam with a certain divergence angle. After the radar laser beam is emitted, it will expand to form a large area of ​​light spot, resulting in less laser energy irradiated on the target object and unable to meet the test requirements. The collimating lens has the function of reducing the emission angle of the radar laser beam and realizing the collimation of the radar laser beam, so as to ensure that the laser energy irradiated on the target object can meet the test requirements.

[0038] The laser light source of a single-point lidar is generally an infrared laser light source with an invisible wavelength. When the invisible light single-point lidar detects a target, it is necessary to confirm whether the lidar is aligned with the target. However, since the laser light source of the lidar is invisible light, the human eye cannot directly confirm whether the laser is irradiated on the target. When using infrared color display cards or infrared cameras to confirm the laser irradiation position, there will be the defect of increasing time and equipment costs.

[0039] In view of this, an embodiment of the present invention provides a laser radar light output position calibration system, which adds a visible light path and realizes coaxial emission of the visible light path and the radar laser light path through optical elements, so that when the radar laser beam is irradiated onto the target object, there is a visible light spot visible to the naked eye on the surface of the target object. In this way, the irradiation position of the radar laser beam can be directly determined during use, thereby improving the efficiency of the laser radar in aligning the target object to be measured and reducing the time cost and equipment cost of the laser radar alignment and debugging.

[0040] like Figure 1 and Figure 2As shown, an embodiment of the present invention provides a laser radar light output position calibration system, including a first collimation unit 100, a visible light output unit 300 and an optical beam combining unit 200; the first collimation unit 100 is used to collimate the radar laser beam output by the laser radar to be tested, and input the collimated radar laser beam to the optical beam combining unit 200, wherein the radar laser beam is invisible light; the visible light output unit 300 is used to generate a visible light beam, and output the visible light beam to the optical beam combining unit 200; the optical beam combining unit 200 is used to change the emission direction of the visible light beam, so that the visible light beam and the radar laser beam are collimated and emitted coaxially.

[0041] Specifically, the laser radar to be tested outputs a radar laser beam through its internal radar laser light source 1, which generally adopts a semiconductor laser. The laser radar light output position calibration system of the embodiment of the present invention is used to test whether the radar laser beam emitted by the radar laser light source 1 reaches the target position.

[0042] In one example, the radar laser beam is an infrared beam, and the visible light beam is a red light beam.

[0043] The radar laser light source 1 inside the laser radar to be tested generally outputs a radar laser beam with a certain divergence angle. After being emitted, the radar laser beam will expand to form a large-area light spot, resulting in less laser energy irradiated on the target object and failing to meet the test requirements. Therefore, by setting the first collimation unit 100 to collimate the radar laser beam, the radar laser beam emission angle can be reduced and the radar laser beam can be collimated, thereby ensuring that the laser energy irradiated on the target object can meet the test requirements.

[0044] In one example, the first collimating unit 100 includes a first collimating lens 2 , and the radar laser beam output by the laser radar to be tested is collimated by the first collimating lens 2 and then input into the optical beam combining unit 200 .

[0045] The radar laser light source 1 is placed at the object focus of the first collimating lens 2 so that the radar laser light beam emitted by the radar laser light source 1 is collimated into parallel light after passing through the first collimating lens 2.

[0046] The radar laser beam is collimated by the first collimating lens 2 to reduce the emission angle of the radar laser beam and achieve the collimation of the radar laser beam, thereby ensuring that the laser energy irradiated on the target object can meet the test requirements.

[0047] The visible light output unit 300 calibrates the light output position by outputting a visible light beam, and the wavelength of the visible light beam is between 780nm and 400nm. The visible light output unit 300 can use a laser or other lighting light source. Exemplarily, the visible light output unit 300 can select a red light semiconductor laser or other visible light band laser to output a visible light beam.

[0048] The optical beam combining unit 200 uses optical lenses such as a reflector to change the emission direction of the visible light beam, so that the visible light beam and the radar laser beam are emitted coaxially, and a lens combination such as a convex lens and a concave lens can be used to collimate the visible light beam and the radar laser beam, so that they are emitted as parallel light. In this way, the emission optical paths of the visible light beam and the radar laser beam coincide, and the position of the radar laser beam can be known by observing the position where the visible light beam irradiates the target object.

[0049] The laser radar light output position calibration system of the embodiment of the present invention collimates and coaxially emits the radar laser beam collimated by the first collimation unit 100 and the visible light beam output by the visible light output unit 300 through the optical beam combining unit 200, so that the optical path of the visible light beam is the same as the optical path of the radar laser beam output by the laser radar to be tested. Therefore, the position of the radar laser beam irradiated on the target object can be determined by observing the position of the visible light beam, and the irradiation position of the laser radar output light can be quickly confirmed without the aid of external infrared color display cards or infrared cameras, thereby improving the efficiency of the laser radar in aligning the target object and reducing the time cost and equipment cost of the laser radar alignment and debugging.

[0050] In some embodiments, the optical beam combining unit 200 includes a dichroic mirror 3 and a second collimating unit; the dichroic mirror 3 is used to transmit the collimated radar laser beam to the optical beam combining unit 200, and reflect the visible light beam to the optical beam combining unit 200 to change the emission direction of the visible light beam so that the visible light beam and the radar laser beam are coaxially emitted; the second collimating unit is used to collimate the visible light beam and the radar laser beam.

[0051] The dichroic mirror 3 is an optical device that can separate light beams according to wavelengths. The two sides of the dichroic mirror are coated with a reflective film and an anti-reflection film for light beams of different wavelengths, respectively, and exhibit high transmittance or high reflection properties for light beams of different wavelengths.

[0052] One side of the dichroic mirror 3 in the embodiment of the present invention is coated with an anti-reflection film for the wavelength band corresponding to the radar laser beam, and the other side is coated with a reflective film for the wavelength band corresponding to the visible light beam. Therefore, it has high reflective properties for the visible light beam and high transmittance properties for the radar laser beam.

[0053] By utilizing the characteristics of the dichroic mirror 3, coaxial emission of light beams of different wavelengths (radar laser beam and visible light beam) is achieved, and the collimation of the visible light beam and the radar laser beam is further ensured by the second collimation unit, thereby enhancing the overlap effect of the light beams after emission.

[0054] Furthermore, the emitting direction of the radar laser beam output by the laser radar to be tested is perpendicular to the emitting direction of the visible light beam output by the visible light output unit 300, and the emitting directions of the visible light beam output by the dichroic mirror 3 and the visible light beam output by the visible light output unit 300 are at 45°.

[0055] In this method, since the light emitting directions of the visible light beam output by the dichroic mirror 3 and the visible light output unit 300 are 45°, the propagation direction of the visible light beam will rotate 90° clockwise and be coaxial with the propagation direction of the radar laser light source 1. By setting the angle of the dichroic mirror 3 to change the direction of the visible light beam, it is ensured that the radar laser beam and the visible light beam are emitted coaxially.

[0056] In some embodiments, the visible light output unit 300 includes a visible light source 6 and an imaging lens 7; the visible light source 6 is used to generate and output the visible light beam; the imaging lens 7 is used to image the visible light beam output by the visible light source 6 onto the dichroic mirror 3.

[0057] Specifically, the visible light source 6 is a semiconductor laser, which has the advantages of small size, low energy consumption, long life, etc., and improves the portability and economy of the system.

[0058] In one example, the imaging lens 7 images the visible light beam output by the visible light source 6 onto the center position of the first surface of the dichroic mirror 3 .

[0059] Assume that the distance between the visible light source 6 and the imaging lens 7 is l, the focal length of the imaging lens 7 is f', and the distance between the visible light image point formed by the imaging lens 7 and the imaging lens 7 is l', then l' is determined by the imaging formula, which is as follows:

[0060]

[0061] According to the imaging formula, when the distance l between the visible light source 6 and the imaging lens 7 and the focal length f′ of the imaging lens 7 are known, the distance l′ between the visible light image point and the imaging lens 7 can be calculated, and then the distance between the imaging lens 7 and the dichroic mirror 3 can be determined.

[0062] In this manner, a visible light source 6 is used to generate a visible light beam, which improves the stability of the light source and the quality of the light beam. The visible light beam is accurately imaged on the dichroic mirror 3 through the imaging lens 7, further ensuring the coaxiality of the light beam and the accuracy of calibration.

[0063] In some embodiments, the second collimating unit includes a focusing lens 4 and a second collimating lens 5; the focusing lens 4 is used to focus the radar laser beam at a first focal position of the second collimating lens 5 corresponding to the wavelength of the radar laser beam, and to image the visible light beam at a second focal position of the second collimating lens 5 corresponding to the wavelength of the visible light beam; the second collimating lens 5 is used to collimate the visible light beam and the radar laser beam for output.

[0064] Specifically, the emitting direction of the radar laser light beam output by the radar laser light source 1 is perpendicular to the emitting direction of the visible light source 6. The radar laser light source 1 is placed at the object focus of the first collimating lens 2. The emitted radar laser light beam passes through the first collimating lens 2 to form collimated light and is emitted to the dichroic mirror 3. After passing through the dichroic mirror 3, it is converged by the focusing lens 4 to the image focus of the focusing lens 4. The image focus of the focusing lens 4 coincides with the object focus of the second collimating lens 5 corresponding to the wavelength of the radar laser light beam. In this way, the radar laser light beam is collimated by the second collimating lens 5 and then emitted to irradiate the target object.

[0065] The imaging lens 7 images the visible light beam output by the visible light source 6 to the center position of the first surface of the dichroic mirror 3, and reflects the visible light beam to the focusing lens 4 through the dichroic mirror 3. The imaging position is located at the object focus of the second collimating lens 5 corresponding to the wavelength of the visible light beam. The visible light beam is collimated after being acted upon by the second collimating lens 5 and is emitted coaxially with the radar laser beam.

[0066] It should be understood that the focal length of the same lens is different for light beams of different wavelengths. The larger the wavelength, the larger the corresponding focal length. Therefore, the lens will have positional chromatic aberration for light beams of different wavelengths, and the existence of positional chromatic aberration will lead to poor light beam overlap.

[0067] Positional chromatic aberration is also called spherical chromatic aberration or axial chromatic aberration. It means that the focal points of light beams of different wavelengths are located at different positions along the axis after passing through the lens. Figure 3 As shown. According to the principle of reversible optical path, the light source must be placed at the corresponding focus to be collimated by the lens, that is, a blue wavelength point light source placed at the corresponding focus will be collimated by the lens, while a red wavelength point light source placed at the focus position of a blue wavelength point light source cannot be collimated by the lens. Therefore, when two point light sources of different wavelengths are at corresponding focal positions, light of both wavelengths can be collimated and the influence of chromatic aberration can be reduced.

[0068] To address the chromatic aberration phenomenon, by adjusting the position of the focusing lens 4, the radar laser beam is focused at the first focal position of the second collimating lens 5 corresponding to the wavelength of the radar laser beam, and the visible light beam is imaged at the second focal position of the second collimating lens 5 corresponding to the wavelength of the visible light beam, so that light of two wavelengths can be collimated and emitted, reducing the influence of chromatic aberration and improving the overlap of the light beams.

[0069] Specifically, the focal length of the second collimating lens 5 corresponding to the wavelength of the radar laser beam and the focal length corresponding to the wavelength of the visible light beam are obtained according to the lens data. Then, the distance of the first focal position relative to the second collimating lens 5 is the focal length of the second collimating lens 5 corresponding to the wavelength of the radar laser beam, and the distance of the second focal position relative to the second collimating lens 5 is the focal length of the second collimating lens 5 corresponding to the wavelength of the visible light beam.

[0070] It should be understood that the radar laser beam is collimated light when it is incident on the focusing lens 4, and will be focused to the image focus by the focusing lens 4. The position of the image focus with respect to the focusing lens 4 is fixed and will not change as the focusing lens 4 moves left and right.

[0071] As for the visible light beam output by the visible light source 6, it is imaged to the focusing lens 4 through secondary imaging, and the position of its image point relative to the focusing lens 4 is adjustable. According to the above imaging formula, when the focal length is determined, the focusing lens 4 is moved left and right, and its object distance (i.e., the distance between the dichroic mirror 3 and the focusing lens 4) and the image distance (the distance between the focusing lens 4 and the image point) are constantly changing. Therefore, the image point position of the visible light beam can be changed by changing the position of the focusing lens 4 relative to the dichroic mirror 3. By changing the image point position, the focusing point of the radar laser light source 1 and the image point of the visible light source 6 can be respectively located at the focal position of the corresponding wavelength of the second collimating lens 5, thereby realizing the collimated emission of point light sources of different wavelengths by the same lens, reducing the influence of chromatic aberration on beam collimation, and ensuring beam coincidence.

[0072] Furthermore, in order to ensure that the focusing lens 4 can focus the radar laser beam at the first focal position of the second collimating lens 5 corresponding to the wavelength of the radar laser beam, and image the visible light beam at the second focal position of the second collimating lens 5 corresponding to the wavelength of the visible light beam, so as to reduce the influence of chromatic aberration on the beam collimation effect, the positions of the focusing lens 4 and the second collimating lens 5 satisfy the following relationship:

[0073] D1=a+b

[0074]

[0075] In the formula, D1 is the distance between the focusing lens 4 and the second collimating lens 5, D2 is the distance between the focusing lens 4 and the dichroic mirror 3, a is the focal length of the second collimating lens 5 corresponding to the wavelength of the radar laser beam, b is the focal length of the second collimating lens 5 corresponding to the wavelength of the visible light beam, and c is the focal length of the focusing lens 4 corresponding to the wavelength of the visible light beam.

[0076] By adjusting the positions of the focusing lens 4 and the second collimating lens 5 through the above formula, the focusing lens 4 can focus the radar laser beam at the first focal position of the second collimating lens 5 corresponding to the wavelength of the radar laser beam, and image the visible light beam at the second focal position of the second collimating lens 5 corresponding to the wavelength of the visible light beam, thereby ensuring that light beams of different wavelengths are imaged at their respective focal positions and then collimated and emitted, avoiding the problem of poor light beam overlap caused by positional chromatic aberration of the second collimating lens 5, thereby improving the optical performance and calibration accuracy of the system.

[0077] The laser radar light output position calibration system of the embodiment of the present invention realizes the coaxial collimated output of the visible light beam and the radar laser beam through simple optical devices such as lenses and dichroic lenses. The visible light beam and the radar laser beam can be simultaneously irradiated onto the surface of the target object. By observing the light spot position of the visible light beam on the surface of the target object with the naked eye, it is possible to confirm whether the laser radar to be tested is aligned with the target. The irradiation position of the laser radar output light can be quickly confirmed without the aid of external infrared color display cards or infrared cameras, thereby improving the efficiency of the laser radar in aligning with the target object and reducing the time cost and equipment cost of the laser radar alignment and debugging.

[0078] Although example embodiments and their advantages have been described in detail, those skilled in the art may make various changes, substitutions and modifications to these embodiments without departing from the spirit and defined scope of the present invention, and such modifications and variations are all within the defined scope.

Claims

1. A laser radar light output position calibration system, characterized in that: It comprises a first collimating unit (100), a visible light output unit (300) and an optical beam combining unit (200); The first collimation unit (100) is used to collimate the radar laser beam output by the laser radar to be tested, and input the collimated radar laser beam into the optical beam combining unit (200), wherein the radar laser beam is invisible light; The visible light output unit (300) is used to generate a visible light beam and output the visible light beam to the optical beam combining unit (200); The optical beam combining unit (200) is used to change the emission direction of the visible light beam so that the visible light beam and the radar laser beam are collimated and emitted coaxially.

2. The laser radar light output position calibration system according to claim 1, characterized in that: The optical beam combining unit (200) comprises a dichroic mirror (3) and a second collimating unit; The dichroic mirror (3) is used to transmit the collimated radar laser beam to the optical beam combining unit (200), and reflect the visible light beam to the optical beam combining unit (200), so as to change the emission direction of the visible light beam, so that the visible light beam and the radar laser beam are emitted coaxially; The second collimation unit is used to collimate the visible light beam and the radar laser beam.

3. The laser radar light output position calibration system according to claim 2, characterized in that: The second collimating unit comprises a focusing lens (4) and a second collimating lens (5); The focusing lens (4) is used to focus the radar laser beam at a first focal position of the second collimating lens (5) corresponding to the wavelength of the radar laser beam, and to image the visible light beam at a second focal position of the second collimating lens (5) corresponding to the wavelength of the visible light beam; The second collimating lens (5) is used for collimating the visible light beam and the radar laser beam for output.

4. The laser radar light output position calibration system according to claim 2 or 3, characterized in that: The visible light output unit (300) comprises a visible light source (6) and an imaging lens (7); The visible light source (6) is used to generate and output the visible light beam; The imaging lens (7) is used to image the visible light beam output by the visible light source (6) onto the dichroic mirror (3).

5. The laser radar light output position calibration system according to claim 2, characterized in that: The light-emitting direction of the radar laser beam output by the laser radar to be tested is perpendicular to the light-emitting direction of the visible light beam output by the visible light output unit (300), and the light-emitting directions of the visible light beam output by the dichroic mirror (3) and the visible light beam output by the visible light output unit (300) are at 45 degrees.

6. The laser radar light output position calibration system according to claim 3, characterized in that: The positions of the focusing lens (4) and the second collimating lens (5) satisfy the following relationship: D1=a+b In the formula, D1 is the distance between the focusing lens (4) and the second collimating lens (5), D2 is the distance between the focusing lens (4) and the dichroic mirror (3), a is the focal length of the second collimating lens (5) corresponding to the wavelength of the radar laser beam, b is the focal length of the second collimating lens (5) corresponding to the wavelength of the visible light beam, and c is the focal length of the focusing lens (4) corresponding to the wavelength of the visible light beam.

7. The laser radar light output position calibration system according to claim 4, characterized in that: The visible light source (6) is a semiconductor laser.

8. The laser radar light output position calibration system according to claim 1, characterized in that: The first collimating unit (100) comprises a first collimating lens (2), and the radar laser beam output by the laser radar to be tested is collimated by the first collimating lens (2) and then input into the optical beam combining unit (200).

Images