Adjusting device for laser radar photoelectric detector

Abstract

The utility model provides a laser radar photoelectric detector adjusting device which comprises a two-dimensional adjusting table, a height adjusting table arranged on the two-dimensional adjusting table, a rotating table arranged on the height adjusting table, a detector fixing seat arranged on the rotating table, a photoelectric detector array arranged in the center of the detector fixing seat, and a lens barrel provided with a receiving lens. The center axis of the receiving lens is aligned with the rotating shaft of the rotating table, and a light through hole is formed in the side, connected with the detector fixing base, of the lens barrel.

Description

Technical Field

[0001] This utility model relates to the field of lidar, and in particular to a lidar photoelectric detector adjustment device. Background Technology

[0002] LiDAR, as a high-precision ranging and imaging technology, is widely used in fields such as autonomous driving, robot navigation, and surveying. To enable the radar's photodetector to acquire as much target light radiation information as possible, a converging optics system must be used to focus the light signal from a distance onto the detector's photosensitive surface. The final receiving efficiency affects the photocurrent signal-to-noise ratio and ranging accuracy. For multi-line lidar, the detector needs to receive reflected signals from multiple laser beams. During assembly and adjustment, each receiving channel must be precisely aligned, placing high demands on the debugging fixtures and operating techniques. Utility Model Content

[0003] This invention provides a laser radar photoelectric detector adjustment device, which solves the problem of detector receiving channel alignment.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a laser radar photoelectric detector adjustment device, including a two-dimensional adjustment platform, a height adjustment platform on the two-dimensional adjustment platform, a rotating platform on the height adjustment platform, a detector fixing seat on the rotating platform, a photoelectric detector array in the center of the detector fixing seat, a receiving lens on the lens barrel, the central axis of the receiving lens being aligned with the rotation axis of the rotating platform, and a light-transmitting hole on the side of the lens barrel connected to the detector fixing seat.

[0005] In the preferred embodiment, a centrally hollowed-out transition plate is provided between the detector mounting base and the lens barrel. One side of the transition plate is connected to the detector mounting base. An adjustment hole is provided on the outer edge of the detector mounting base. A pin is provided in the adjustment hole. One end of the pin is connected to the other side of the transition plate. The diameter of the adjustment hole is larger than the diameter of the pin. An adjustment gap is provided between the detector mounting base and the transition plate.

[0006] In a preferred embodiment, the two-dimensional adjustment stage includes a first base, on which a slidingly connected X-axis displacement stage is provided, and on which a slidingly connected Y-axis displacement stage is provided, with the movement directions of the X-axis displacement stage and the Y-axis displacement stage being perpendicular.

[0007] In the preferred embodiment, the outer wall of the first base is provided with a first connecting ear, and the first connecting ear is provided with a threaded first adjusting rod. The outer wall of the X-axis displacement stage is provided with a second connecting ear, and one end of the first adjusting rod is rotatably connected to the second connecting ear. The outer wall of the X-axis displacement stage is also provided with a third connecting ear, and the third connecting ear is provided with a threaded second adjusting rod. The outer wall of the Y-axis displacement stage is provided with a fourth connecting ear, and one end of the second adjusting rod is rotatably connected to the fourth connecting ear.

[0008] In a preferred embodiment, the height adjustment platform includes a second base, a fixed wedge block and a sliding wedge block are provided inside the second base, the wedge surfaces of the sliding wedge block and the fixed wedge block are in contact with each other, a third adjustment rod is provided on the second base with a threaded connection, one end of the third adjustment rod is rotatably connected to the sliding wedge block, a Z-axis displacement stage is also provided on one side of the sliding wedge block inside the second base, and a retaining spring is provided between the second base and the Z-axis displacement stage.

[0009] In a preferred embodiment, the rotary table includes a third base, on which a rotatable rotating block is mounted. A detector mounting base is connected to the rotating block. The outer wall of the third base is provided with a fifth connecting ear, which has a U-shaped groove. Each side wall of the U-shaped groove is provided with a threaded fourth adjusting rod. The outer wall of the rotating block is provided with an extension lever, and the end of the fourth adjusting rod abuts against the side wall of the extension lever.

[0010] The beneficial effects of this invention are as follows: multiple detectors are integrated onto a printed circuit board and uniformly adjusted using a displacement stage, eliminating the need for individual adjustment of each receiving channel; multi-dimensional adjustments such as translation, rotation, and spacing are employed, enabling highly efficient focusing of the detector array and improving photoelectric conversion efficiency. Attached Figure Description

[0011] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0012] Figure 1 This is a schematic diagram of the present invention.

[0013] Figure 2 This is a structural diagram of the present invention.

[0014] Figure 3 This is a structural diagram of the internal structure of the two-dimensional adjustment platform of this utility model.

[0015] Figure 4 This is a diagram of the internal structure of the height adjustment platform of this utility model.

[0016] Figure 5 This is a diagram of the rotating structure of the rotating table of this utility model.

[0017] Figure 6 This is a schematic diagram of the rotating shaft of the rotary table of this utility model.

[0018] Figure 7 This is a schematic diagram of the four-way return light path of this utility model.

[0019] In the figure: 2D adjustment stage 1; first base 101; X-axis displacement stage 102; Y-axis displacement stage 103; first connecting ear 104; second connecting ear 105; first adjusting rod 106; annular groove 107; locking pin 108; third connecting ear 109; second adjusting rod 110; fourth connecting ear 111; height adjustment stage 2; second base 201; fixed wedge block 202; sliding wedge block 203; Z-axis displacement stage 204; third adjusting rod 205; retaining spring 206; rotary stage 3; third base 301; rotating block 302; outward extension lever 303; fifth connecting ear 304; U-shaped groove 305; fourth adjusting rod 306; detector fixing seat 4; photodetector array 401; adjusting hole 402; lens barrel 5; light receiving structure 501; pin 502; light transmission hole 503; receiving lens 6; transition plate 7. Detailed Implementation

[0020] Example 1:

[0021] like Figure 1-7 A laser radar photoelectric detector adjustment device includes a two-dimensional adjustment platform 1, a height adjustment platform 2 on the two-dimensional adjustment platform 1, a rotating platform 3 on the height adjustment platform 2, a detector fixing seat 4 on the rotating platform 3, a photoelectric detector array 401 in the center of the detector fixing seat 4, a lens barrel 5 with a receiving lens 6, the central axis of the receiving lens 6 being aligned with the rotation axis of the rotating platform 3, and a light-transmitting hole 503 on the side of the lens barrel 5 connected to the detector fixing seat 4.

[0022] The two-dimensional adjustment stage 1 can adjust the displacement of the detector mounting base 4 in two orthogonal directions on the plane; the height adjustment stage 2 can adjust the distance between the detector mounting base 4 and the receiving lens 6; and the rotation stage 3 can adjust the rotation angle of the detector mounting base 4.

[0023] The lens tube 5 is equipped with a light-collecting structure 501.

[0024] In a preferred embodiment, a centrally hollowed-out transition plate 7 is provided between the detector mounting base 4 and the lens barrel 5. One side of the transition plate 7 is connected to the detector mounting base 4. An adjustment hole 402 is provided on the outer edge of the detector mounting base 4. A pin 502 is provided in the adjustment hole 402. One end of the pin 502 is connected to the other side of the transition plate 7. The diameter of the adjustment hole 402 is larger than the diameter of the pin 502. An adjustment gap is provided between the detector mounting base 4 and the transition plate 7.

[0025] The transition plate 7 has a central cutout for light transmission.

[0026] The lens barrel 5 is connected to the lidar body and is a fixed component. The detector mounting base 4 can be adjusted in position by the two-dimensional adjustment stage 1, the height adjustment stage 2, and the rotary stage 3. Therefore, the detector mounting base 4 is a movable component relative to the lens barrel 5. A transition plate 7 can be installed on the end flange of the lens barrel 5. The transition plate 7 is removable for easy replacement.

[0027] In a preferred embodiment, the two-dimensional adjustment stage 1 includes a first base 101, on which a slidingly connected X-axis displacement stage 102 is provided, and on which a slidingly connected Y-axis displacement stage 103 is provided, wherein the moving directions of the X-axis displacement stage 102 and the Y-axis displacement stage 103 are perpendicular.

[0028] After the position of the photodetector array 401 is adjusted, the pin 502 is welded to the adjustment hole 402 and fixed together, and the gap between the detector fixing seat 4 and the transition plate 7 is welded to fix the position of the photodetector array 401. Then the adjustment structure including the two-dimensional adjustment stage 1, the height adjustment stage 2 and the rotary stage 3 is removed.

[0029] In a preferred embodiment, the outer wall of the first base 101 is provided with a first connecting ear 104, and the first connecting ear 104 is provided with a threaded first adjusting rod 106. The outer wall of the X-axis displacement stage 102 is provided with a second connecting ear 105, and one end of the first adjusting rod 106 is rotatably connected to the second connecting ear 105. The outer wall of the X-axis displacement stage 102 is also provided with a third connecting ear 109, and the third connecting ear 109 is provided with a threaded second adjusting rod 110. The outer wall of the Y-axis displacement stage 103 is provided with a fourth connecting ear 111, and one end of the second adjusting rod 110 is rotatably connected to the fourth connecting ear 111.

[0030] The first adjusting rod 106 has an annular groove 107 at one end, and the second connecting ear 105 has a retaining pin 108 inserted into the annular groove 107. The retaining pin 108 is a set screw that is threadedly connected to the second connecting ear 105, and the insertion depth can be adjusted without affecting the relative rotation between the first adjusting rod 106 and the second connecting ear 105.

[0031] In a preferred embodiment, the height adjustment platform 2 includes a second base 201, a fixed wedge block 202 and a sliding wedge block 203 are provided inside the second base 201, the wedge surfaces of the sliding wedge block 203 and the fixed wedge block 202 are in contact with each other, a threaded third adjustment rod 205 is provided on the second base 201, one end of the third adjustment rod 205 is rotatably connected to the sliding wedge block 203, a Z-axis displacement platform 204 is also provided on one side of the sliding wedge block 203 inside the second base 201, and a retaining spring 206 is provided between the second base 201 and the Z-axis displacement platform 204.

[0032] The second base 201 is connected to the Y-axis displacement stage 103.

[0033] The third adjusting rod 205 rotates to push the sliding wedge block 203 to move along the wedge surface of the fixed wedge block 202, so as to push the Z-axis displacement stage 204 out of the cavity of the second base 201. The Z-axis displacement stage 204 is provided with a flange, and the cavity opening of the second base 201 is provided with a narrow opening. The narrow opening and the flange form a cavity to accommodate the retaining spring 206. When the third adjusting rod 205 reverses, the retaining spring 206 pushes the flange of the Z-axis displacement stage 204 to retract it.

[0034] The third adjusting rod 205 is connected to the sliding wedge block 203 by using a set screw to lock the annular groove.

[0035] In a preferred embodiment, the rotating platform 3 includes a third base 301, on which a rotatable rotating block 302 is provided. The detector fixing seat 4 is connected to the rotating block 302. The outer wall of the third base 301 is provided with a fifth connecting ear 304. The fifth connecting ear 304 is provided with a U-shaped groove 305. Each side wall of the U-shaped groove 305 is provided with a threaded fourth adjusting rod 306. The outer wall of the rotating block 302 is provided with an extension lever 303. The end of the fourth adjusting rod 306 abuts against the side wall of the extension lever 303.

[0036] The third base 301 is connected to the Z-axis displacement stage 204.

[0037] The third base 301 has a circular recess in the center, and the rotating block 302 has a cylindrical protrusion in the center of its side. The two work together to allow the rotating block 302 to rotate relative to the third base 301. Two fourth adjusting rods 306 clamp the extension lever 303 in the middle. The circumferential position of the extension lever 303 can be adjusted by adjusting the extension of the two fourth adjusting rods 306 to change the angle of the detector fixing seat 4.

[0038] Example 2:

[0039] An adjustable photodetector device for lidar is disclosed for assembling the light-receiving system of a multi-line lidar system, maximizing photoelectric conversion efficiency. The device comprises an optical receiving lens, a photodetector array, a welding base, and an adjustable displacement stage, wherein the adjustable displacement stage includes a triaxial linear displacement stage and a rotary stage. Figure 1As shown, the receiving lens focuses the weak laser signal reflected from the target onto the focal plane. One or more spherical or aspherical lenses are used to eliminate field curvature and spherical aberration during focusing. The photodetector array is fixed on a rotating stage of an adjustable displacement stage. While monitoring the signal intensity of the photosensitive surfaces, the operator rotates the micrometer heads along each axis, moving and rotating the detector array near the focal plane. First, a coarse adjustment is performed, adjusting the rotating stage to align the line connecting the photosensitive surfaces parallel to the line connecting the focused spot, ensuring that the signal intensity of each detector exhibits the same trend when defocusing. Then, the three-axis displacement stage is adjusted to precisely move the detector array to the focal position, achieving maximum receiving efficiency. This device is simple to use, structurally stable, and has high adjustment accuracy.

[0040] The received light of a multi-line lidar comes from the scattering of the surface of the target under test. It consists of multiple beams with a certain angle between them. Aspherical or spherical lens groups can be used to reduce aberrations, minimize the focusing spot radius of the off-axis beam, and keep the focus of the multiple beams on the same plane as much as possible. In this device, a single aspherical lens is used to focus four backlights, which reduces the complexity of the system and helps to adjust the four signals to the maximum at the same time.

[0041] The photodetector array consists of four photodiodes arranged linearly and soldered onto a signal amplification and processing circuit. The area of ​​the photosensitive surface is significantly larger than the spot size of the geometric optics simulation, which can reduce the impact of detector position errors. The printed circuit board containing the detector array is fixed to the detector mount with screws. The detector mount is then fixed to a rotary table through threaded holes at the four corners. The rotary table is connected to z-axis, y-axis, and x-axis displacement stages to allow for multi-dimensional adjustment of the detector mount's position.

[0042] The multi-line radar has a welding base at the end of the light-receiving structure, used to weld and fix the detector in place after adjustment. During debugging, the detector mounting base is first adjusted to be close to the focal plane of the lens. At this time, the pin on the edge of the welding base passes through the corresponding through hole on the edge of the detector mounting base. The detector mounting base is then adjusted visually to center the pin in the through hole, completing the initial positioning of the detector array. The amplified output of the photodiode is connected to an oscilloscope to monitor the photocurrent signal in real time.

[0043] First, the z-axis position of the detector mount is adjusted individually. The photocurrent signal decreases as the defocus distance of the photosensitive surface on the optical axis increases. When the signal amplitude is at its maximum, the photosensitive surface is closest to the focal plane. Then, the x-axis displacement stage is adjusted to the maximum signal amplitude peak, allowing the focused spot to fall as close to the photosensitive surface as possible. Next, the y-axis displacement stage is adjusted simultaneously with the rotary stage, ensuring that the signal amplitudes of different detectors in the array reach their maximum values ​​at the same y-axis position. At this point, the focused spots of the four returning beams are all located at the center of the corresponding detector's photosensitive surface, completing the focusing process. Finally, solder is used to cover all the pins of the mounting base and the through holes of the detector mount, using two or more solder points to fix the detector array to the radar main structure.

[0044] By integrating multiple detectors onto a printed circuit board and using a displacement stage for unified adjustment, individual adjustments to the receiving efficiency of each detector are unnecessary. By improving the aberration correction capability of the receiving optical system, this adjustment device is applicable to lidars with different line counts and field of view angles, exhibiting excellent compatibility and operability. In the receiving system, a refractive optical system, in conjunction with a multi-dimensional displacement stage, adjusts multiple optical detectors to the focal position simultaneously, significantly improving the adjustment efficiency of multi-line lidars.

[0045] The above embodiments are merely preferred technical solutions of this utility model and should not be considered as limitations on this utility model. The protection scope of this utility model should be the technical solution described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the protection scope of this utility model.

Claims

1. A lidar photoelectric detector adjustment device, characterized in that: It includes a two-dimensional adjustment stage (1), a height adjustment stage (2) on the two-dimensional adjustment stage (1), a rotating stage (3) on the height adjustment stage (2), a detector mounting base (4) on the rotating stage (3), a photoelectric detector array (401) in the center of the detector mounting base (4), a receiving lens (6) on the lens barrel (5), the central axis of the receiving lens (6) is aligned with the rotation axis of the rotating stage (3), and a light-transmitting hole (503) is provided on the side of the lens barrel (5) connected to the detector mounting base (4).

2. The lidar photodetector adjustment device according to claim 1, characterized in that: A centrally hollow transition plate (7) is provided between the detector mounting base (4) and the lens tube (5). One side of the transition plate (7) is connected to the detector mounting base (4). An adjustment hole (402) is provided on the outer edge of the detector mounting base (4). A pin (502) is provided in the adjustment hole (402). One end of the pin (502) is connected to the other side of the transition plate (7). The diameter of the adjustment hole (402) is larger than the diameter of the pin (502). An adjustment gap is provided between the detector mounting base (4) and the transition plate (7).

3. The lidar photodetector adjustment device according to claim 1, characterized in that: two-dimensional... The adjustment platform (1) includes a first base (101), on which a slidingly connected X-axis displacement platform (102) is provided, and on which a slidingly connected Y-axis displacement platform (103) is provided, and the moving directions of the X-axis displacement platform (102) and the Y-axis displacement platform (103) are perpendicular.

4. The lidar photodetector adjustment device according to claim 3, characterized in that: The outer wall of the first base (101) is provided with a first connecting ear (104), and the first connecting ear (104) is provided with a first adjusting rod (106) with a threaded connection. The outer wall of the X-axis displacement stage (102) is provided with a second connecting ear (105), and one end of the first adjusting rod (106) is rotatably connected to the second connecting ear (105). The outer wall of the X-axis displacement stage (102) is also provided with a third connecting ear (109), and the third connecting ear (109) is provided with a second adjusting rod (110) with a threaded connection. The outer wall of the Y-axis displacement stage (103) is provided with a fourth connecting ear (111), and one end of the second adjusting rod (110) is rotatably connected to the fourth connecting ear (111).

5. The lidar photodetector adjustment device according to claim 1, characterized in that: The height adjustment platform (2) includes a second base (201), a fixed wedge block (202) and a sliding wedge block (203) are provided in the second base (201), the wedge surfaces of the sliding wedge block (203) and the fixed wedge block (202) are in contact with each other, a third adjustment rod (205) with a threaded connection is provided on the second base (201), one end of the third adjustment rod (205) is rotatably connected to the sliding wedge block (203), a Z-axis displacement stage (204) is also provided on one side of the sliding wedge block (203) in the second base (201), and a retaining spring (206) is provided between the second base (201) and the Z-axis displacement stage (204).

6. The lidar photodetector adjustment device according to claim 1, characterized in that: The rotating platform (3) includes a third base (301), on which a rotatable rotating block (302) is provided. The detector fixing seat (4) is connected to the rotating block (302). The outer wall of the third base (301) is provided with a fifth connecting ear (304). The fifth connecting ear (304) is provided with a U-shaped groove (305). Each side wall of the U-shaped groove (305) is provided with a threaded fourth adjusting rod (306). The outer wall of the rotating block (302) is provided with an extension lever (303). The end of the fourth adjusting rod (306) abuts against the side wall of the extension lever (303).

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