CN-121978659-A - Laser radar device

CN121978659ACN 121978659 ACN121978659 ACN 121978659ACN-121978659-A

Abstract

The invention relates to the technical field of laser radars, in particular to a laser radar device. According to the invention, the flexible dynamic adjustment of the angle of view is realized by integrating the cooperative design of the dual-wavelength coherent detection loop, the dual-vibrating mirror and the rotating mirror. Specifically, the coincidence ratio of the scanning ranges of the signal light with two wavelengths can be changed by adjusting the relative positions and angles of the first vibrating mirror, the second vibrating mirror and the rotating mirror, so that the view angle can be adaptively switched in different application scenes, the coverage area can be enlarged when large-scale detection is needed, and the high-density point cloud scanning can be realized when a local area is concerned. Therefore, the environmental adaptability and the detection efficiency of the laser radar are obviously improved, the detection range and the detection precision are considered, meanwhile, the system integration level and the reliability are enhanced through optical structure multiplexing, and the laser radar is suitable for multi-scene requirements such as automatic driving, robot navigation and the like.

Inventors

GU LINPENG
HAN XIAOXIAO
BAO CHUNGUI

Assignees

杭州洛微科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260204

Claims (10)

1. The laser radar device is characterized by comprising a first wavelength coherent detection loop, a second wavelength coherent detection loop, a first galvanometer, a second galvanometer and a rotating mirror; the first wavelength coherent detection loop is used for dividing a first wavelength optical signal into first wavelength reference light and first wavelength signal light, and inputting the first wavelength signal light into the first galvanometer; the second wavelength coherent detection loop is used for dividing a second wavelength optical signal into second wavelength reference light and second wavelength signal light, and inputting the second wavelength signal light into the second galvanometer; the first galvanometer is used for irradiating the first wavelength signal light to the first surface of the turning mirror; The second galvanometer is used for irradiating the second wavelength signal light to the second surface of the turning mirror; The turning mirror irradiates the first wavelength signal light and the second wavelength signal light on the same target object, receives the first wavelength signal light and the second wavelength signal light reflected by the target object, and after the reflected first wavelength signal light and the reflected second wavelength signal light respectively pass through the first vibrating mirror and the second vibrating mirror, the reflected first wavelength signal light enters the first wavelength coherent detection loop and the first wavelength reference light for coherent detection, and the reflected second wavelength signal light enters the second wavelength coherent detection loop and the second wavelength reference light for coherent detection; When the laser radar device is applied to different scenes, the positions and angles of the first vibrating mirror, the second vibrating mirror and the rotating mirror are different, so that the coincidence degrees of the scanning ranges of the first wavelength signal light and the second wavelength signal light are different, and the field angles of the laser radar device are different.
2. The lidar device of claim 1, further comprising a first rotational axis, a second rotational axis, a slide rail, and a control system; The first vibrating mirror is arranged on the first rotating shaft, the second vibrating mirror is arranged on the second rotating shaft, and the rotating mirror is arranged on the sliding rail; The control system is used for controlling the swing angles of the first vibrating mirror and the second vibrating mirror through the first rotating shaft and the second rotating shaft, changing the position of the rotating mirror through the sliding rail and changing the rotating angle of the rotating mirror.
3. The lidar device according to claim 2, wherein: when the application scene is that the field angle of the laser radar device is larger than the first threshold value, the control system controls the turning mirror to move towards the direction close to the first vibrating mirror and the second vibrating mirror through the sliding rail; when the application scene is that the field angle of the laser radar device is smaller than the field angle of the second threshold, the control system controls the turning mirror to move in the direction away from the first vibrating mirror and the second vibrating mirror through the sliding rail; in different scenes, the control system controls the swing angles of the first vibrating mirror and the second vibrating mirror and the rotation angle of the rotating mirror so as to realize point cloud scanning in the X direction and the Y direction.
4. The lidar device according to claim 2, wherein when the application scene is a view angle at which the view angle of the lidar device is smaller than a second threshold, the control system is further configured to control the oscillation angles of the first oscillating mirror and the second oscillating mirror to be different so that the scanning points of the first wavelength signal light and the second wavelength signal light alternately appear in the Y direction.
5. The lidar device according to claim 1, wherein the first wavelength signal light and the second wavelength signal light have different reflectivities on the same target object, and wherein a coherent detection probability for the target object is larger than a third threshold.
6. The lidar device of claim 1, further comprising a lidar chip and a scanning system, wherein the first wavelength coherent detection loop and the second wavelength coherent detection loop are disposed on the lidar chip, and wherein the first galvanometer, the second galvanometer, and the turning mirror are disposed in the scanning system; The laser radar chip further comprises a beam combination module, wherein the beam combination module is used for combining the first wavelength signal light and the second wavelength signal light to obtain a combined signal, inputting the combined signal into the scanning system, and transmitting the reflected first wavelength signal light and the reflected second wavelength signal light to the first wavelength coherent detection loop and the second wavelength coherent detection loop respectively after splitting the reflected first wavelength signal light and the reflected second wavelength signal light; The scanning system further comprises a beam splitting module, wherein the beam splitting module is used for splitting the beam combination signal, irradiating the first split wavelength signal light to the first vibrating mirror, irradiating the second split wavelength signal light to the second vibrating mirror, and transmitting the reflected first wavelength signal light and the reflected second wavelength signal light to the beam combination module after combining the beam combination signal.
7. The lidar device according to claim 6, wherein the beam combining module comprises a wavelength mixer and an optical spot-converting waveguide; the wavelength mixer is used for combining the first wavelength signal light and the second wavelength signal light to obtain combined signal light; The optical spot-changing waveguide is used for expanding the beam of the combined signal light and inputting the expanded beam into the scanning system; the optical plaque-switching waveguide is further used for transmitting the reflected first wavelength signal light and the second wavelength signal light to the wavelength mixer; The wavelength mixer is further configured to split the reflected first wavelength signal light and the second wavelength signal light.
8. The lidar device according to claim 7, wherein the beam splitting module comprises a collimator mirror and a wavelength splitter; The collimating lens is used for collimating the beam-expanded combined signal light and transmitting the collimated beam-expanded combined signal light to the wavelength beam splitter; The wavelength beam splitter is used for splitting the collimated combined beam signal and then respectively irradiating the collimated combined beam signal to the first vibrating mirror and the second vibrating mirror; the wavelength beam splitter is also used for combining the reflected first wavelength signal light and the reflected second wavelength signal light and transmitting the combined beams to the collimating mirror; The collimating mirror is also used for transmitting the reflected first wavelength signal light and the reflected second wavelength signal light to the optical spot-converting waveguide.
9. The lidar device according to claim 1, wherein the first wavelength coherence detection circuit comprises a first split-waveguide coupler, a second split-waveguide coupler, a third split-waveguide coupler, a first balanced detector, and a first in-waveguide; The first light input waveguide is used for receiving a first wavelength light signal, transmitting the first wavelength light signal to the second light splitting waveguide coupler, the second light splitting waveguide coupler is used for splitting the first wavelength light signal into first wavelength signal light and first wavelength reference light, transmitting the first wavelength reference light to the third light splitting waveguide coupler, transmitting the first wavelength signal light to the first light splitting waveguide coupler, and the first light splitting waveguide coupler is used for outputting the first wavelength signal light; The first light-splitting waveguide coupler is further used for receiving the reflected first wavelength signal light, transmitting the reflected first wavelength signal light to the third light-splitting waveguide coupler, and the third light-splitting waveguide coupler is used for transmitting the first wavelength signal light and the first wavelength reference light to the first balance detector for coherent detection after combining.
10. The lidar device according to claim 1, wherein the second wavelength coherence detection circuit comprises a fourth split-waveguide coupler, a fifth split-waveguide coupler, a sixth split-waveguide coupler, a second balanced detector, and a second in-waveguide; The second light input waveguide is configured to receive a second wavelength light signal, transmit the second wavelength light signal to the fifth light splitting waveguide coupler, the fifth light splitting waveguide coupler is configured to split the second wavelength light signal into a second wavelength signal light and a second wavelength reference light, transmit the second wavelength reference light to the sixth light splitting waveguide coupler, transmit the second wavelength signal light to the fourth light splitting waveguide coupler, and output the second wavelength signal light; The fourth light-splitting waveguide coupler is further configured to receive the reflected second wavelength signal light, transmit the reflected second wavelength signal light to the sixth light-splitting waveguide coupler, and transmit the second wavelength signal light and the second wavelength reference beam after being combined to the second balanced detector for coherent detection.

Description

Laser radar device Technical Field The invention relates to the technical field of laser radars, in particular to a laser radar device. Background The frequency modulation continuous wave (Frequency Modulated Continuous Wave, FMCW) laser radar is widely applied to the fields of roads, warehouse storage, unmanned aerial vehicle cruising and the like, and under different application scenes, the core requirements of the FMCW laser radar are obviously different, for example, certain scenes need to have a large Field of View (FOV) so as to rapidly detect large-scale spatial information, and other scenes need to realize accurate identification on local areas. In the prior art, the common FMCW laser radar is mostly a semi-solid rotating mirror and vibrating mirror laser radar, on one hand, the structure size of the polygon rotating mirror is large, the effective space inside the radar is occupied, only one surface of the polygon rotating mirror is used at the same time, the utilization efficiency is low, on the other hand, the design scheme of the fixed view field is limited, the view field range cannot be dynamically adjusted according to the scene, and the double requirements of 'large-range detection' and 'local accurate identification' are difficult to be considered at the same time, so that the multi-scene adaptation capability is obviously limited. Disclosure of Invention In view of the above, the present invention provides a laser radar apparatus to solve the technical problem that the prior art laser radar has significant limitation on the multi-scene adaptation capability. The technical scheme provided by the invention is as follows: The first aspect of the invention provides a laser radar device, which comprises a first wavelength coherent detection loop, a second wavelength coherent detection loop, a first galvanometer, a second galvanometer and a rotating mirror; the first wavelength coherent detection loop is used for dividing a first wavelength optical signal into first wavelength reference light and first wavelength signal light, and inputting the first wavelength signal light into the first galvanometer; the second wavelength coherent detection loop is used for dividing a second wavelength optical signal into second wavelength reference light and second wavelength signal light, and inputting the second wavelength signal light into the second galvanometer; the first galvanometer is used for irradiating the first wavelength signal light to the first surface of the turning mirror; The second galvanometer is used for irradiating the second wavelength signal light to the second surface of the turning mirror; The turning mirror irradiates the first wavelength signal light and the second wavelength signal light on the same target object, receives the first wavelength signal light and the second wavelength signal light reflected by the target object, and after the reflected first wavelength signal light and the reflected second wavelength signal light respectively pass through the first vibrating mirror and the second vibrating mirror, the reflected first wavelength signal light enters the first wavelength coherent detection loop and the first wavelength reference light for coherent detection, and the reflected second wavelength signal light enters the second wavelength coherent detection loop and the second wavelength reference light for coherent detection; When the laser radar device is applied to different scenes, the positions and angles of the first vibrating mirror, the second vibrating mirror and the rotating mirror are different, so that the coincidence degrees of the scanning ranges of the first wavelength signal light and the second wavelength signal light are different, and the field angles of the laser radar device are different. According to the invention, the flexible dynamic adjustment of the angle of view is realized by integrating the cooperative design of the dual-wavelength coherent detection loop, the dual-vibrating mirror and the rotating mirror. Specifically, the coincidence ratio of the scanning ranges of the signal light with two wavelengths can be changed by adjusting the relative positions and angles of the first vibrating mirror, the second vibrating mirror and the rotating mirror, so that the view angle can be adaptively switched in different application scenes, the coverage area can be enlarged when large-scale detection is needed, and the high-density point cloud scanning can be realized when a local area is concerned. Therefore, the environmental adaptability and the detection efficiency of the laser radar are obviously improved, the detection range and the detection precision are considered, meanwhile, the system integration level and the reliability are enhanced through optical structure multiplexing, and the laser radar is suitable for multi-scene requirements such as automatic driving, robot navigation and the like. In an alternative embodiment, the device further compris