CN115079136A - Solid-state laser radar system and vehicle - Google Patents

Abstract

The present disclosure relates to a solid-state lidar system and a vehicle, the system comprising: the planar array laser is used for emitting signal light and comprises emitting units arranged in an array; an emission lens group; a receiving lens group; the area array detector is used for receiving the echo subjected to convergence processing by the receiving lens group and comprises receiving units arranged in an array; the optical switch is arranged between the receiving lens group and the area array detector and comprises switch subunits arranged in an array; the corresponding proportional relationship between the transmitting unit and the receiving unit is M: 1, M is a positive integer and M > 1; the corresponding proportional relation between the transmitting unit and the switch subunit is N: 1, N is a positive integer and N is less than or equal to M; when the transmitting unit transmits the signal light, the switch subunit corresponding to the transmitting unit is set to be in a light-transmitting state, and other switch subunits are set to be in a light-tight state. Therefore, the resolution ratio is improved, and the overall intensity of the ambient light is reduced, so that the interference of the ambient light on the signal light is reduced, and the signal-to-noise ratio and the detection distance are improved.

Description

Solid-state laser radar system and vehicle

Technical Field

The present disclosure relates to laser radar technology, and more particularly, to a solid state laser radar system and a vehicle.

Background

Because the laser radar has the advantages of high ranging precision and high transverse resolution, the laser radar has wide application prospect in the fields of assistant driving and automatic driving.

Laser radars can be classified into mechanical laser radars, semi-solid laser radars, and solid laser radars according to the scanning mode. The mechanical laser radar has the defects of large volume, easy damage of a rotating structure, poor mass production and the like due to more moving parts, high price and gradually reduced reliability along with time; compared with a mechanical laser radar, the solid laser radar does not need a rotating part, so that the volume is smaller, the integration is convenient in the vehicle body, the system reliability is improved, the cost can be greatly reduced, and the laser radar has the trend of solid development. However, the solid-state lidar still has the problems of low resolution, short detection distance, and susceptibility to ambient light interference.

Disclosure of Invention

In order to solve the technical problem, the present disclosure provides a solid-state lidar system and a vehicle.

The present disclosure provides a solid state lidar system comprising:

an area array laser for emitting signal light; the area array laser comprises emitting units arranged in an array;

the emission lens group is used for projecting the signal light onto a target object after the signal light is collimated;

the receiving lens group is used for receiving the echo of the diffuse reflection of the target object and carrying out convergence processing on the echo;

the area array detector is used for receiving the echo subjected to the convergence processing by the receiving lens group; the area array laser comprises receiving units arranged in an array;

the optical switch is arranged between the receiving lens group and the area array detector and comprises switch subunits arranged in an array;

wherein, the corresponding proportional relation of the transmitting unit and the receiving unit is M: 1, M is a positive integer and M > 1; the corresponding proportional relation between the transmitting unit and the switch subunit is N: 1, N is a positive integer and N is less than or equal to M; when the transmitting unit transmits signal light, the switch subunits corresponding to the transmitting unit are set to be in a light-transmitting state, and other switch subunits are set to be in a light-tight state.

Optionally, the area array laser comprises a vertical cavity surface emitting laser;

and/or the area array detector comprises a silicon photomultiplier array detector.

Optionally, the emission unit emits the signal light according to a preset light emission timing.

Optionally, the optical switch comprises at least one of a reflective optical switch and a transmissive optical switch.

Optionally, the reflective optical switch is configured as a digital micromirror device, and the digital micromirror device includes mirrors arranged in an array.

Optionally, the transmissive optical switch is configured as a liquid crystal optical switch, and the liquid crystal optical switch includes liquid crystal optical switch subunits arranged in an array.

Alternatively, in a solid state lidar system, N is equal to 1.

Optionally, the value range of M includes at least one of 4, 9, and 16.

Optionally, the solid state lidar system further comprises: an optical filter;

the optical filter is arranged between the receiving lens group and the target object and is used for transmitting light rays with the same wave band range as the signal light emitted by the area array laser.

The present disclosure also provides a vehicle comprising: any of the above solid state lidar systems.

Compared with the prior art, the technical scheme provided by the disclosure has the following advantages:

the utility model provides a solid-state laser radar system and vehicle, this solid-state laser radar system includes: an area array laser for emitting signal light; the area array laser comprises emitting units arranged in an array; the emission lens group is used for projecting the signal light onto a target object after the signal light is collimated; the receiving lens group is used for receiving the echo of the diffuse reflection of the target object and converging the echo; the area array detector is used for receiving the echo subjected to convergence processing by the receiving lens group; the area array laser comprises receiving units arranged in an array; the optical switch is arranged between the receiving lens group and the area array detector and comprises switch subunits arranged in an array; wherein, the corresponding proportional relation of the transmitting unit and the receiving unit is M: 1, M is a positive integer and M > 1; the corresponding proportional relation between the transmitting unit and the switch subunit is N: 1, N is a positive integer and N is less than or equal to M; when the transmitting unit transmits the signal light, the switch subunit corresponding to the transmitting unit is set to be in a light-transmitting state, and other switch subunits are set to be in a light-tight state. According to the arrangement, the plurality of transmitting units correspond to one receiving unit, the number of the point clouds received by one receiving unit 141 is changed from one point cloud to M point clouds, under the condition that the angle is not changed, the density of the point clouds is increased, and the resolution of the solid-state laser radar system is further improved; when the transmitting unit transmits the signal light, the on-off state of the switch subunit is controlled, so that only the corresponding region of the receiving unit receives the echo of the signal light, and other regions can not receive the echo of the signal light, thereby reducing the overall intensity of the ambient light, reducing the interference of the ambient light on the signal light, and improving the signal-to-noise ratio and the detection distance.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure.

In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present disclosure, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.

Fig. 1 is a schematic structural diagram of a solid-state lidar system according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of an area array laser according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of an area array detector according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of a corresponding relationship between a transmitting unit and a receiving unit according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a corresponding relationship between an emission unit and an optical switch according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of different states of a mirror in a digital micromirror device according to an embodiment of the disclosure;

fig. 7 is a schematic diagram illustrating an operating principle of a solid-state lidar employing a digital micromirror device according to an embodiment of the disclosure;

FIG. 8 is a schematic diagram of different states of a liquid crystal optical switch subunit in a liquid crystal optical switch provided by an embodiment of the present disclosure;

fig. 9 is a schematic diagram illustrating an operating principle of a solid-state lidar to which a liquid crystal optical switch is applied according to an embodiment of the present disclosure;

fig. 10 provides a schematic structural diagram of another solid-state lidar system according to an embodiment of the disclosure.

100, a solid-state laser radar system; 110. an area array laser; 111. a transmitting unit; 120. an emission lens group; 130. a receiving lens group; 140. an area array detector; 141. a receiving unit; 150. a light switch, 151, a switch subunit; 160. an optical filter; 200. an object is obtained.

Detailed Description

In order that the above objects, features and advantages of the present disclosure may be more clearly understood, aspects of the present disclosure will be further described below. It should be noted that the embodiments and features of the embodiments of the present disclosure may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced in other ways than those described herein; it is to be understood that the embodiments disclosed in the specification are only a few embodiments of the present disclosure, and not all embodiments.

In combination with the background technology, compared with a mechanical laser radar, the solid-state laser radar has the advantages of low cost, miniaturization, good reliability, easiness in mass production and the like, but still has the problems of low resolution, short detection distance, easiness in ambient light interference and the like.

In order to solve the above technical problem, an embodiment of the present disclosure provides a solid-state lidar system and a vehicle, where the solid-state lidar system includes: an area array laser for emitting signal light; the area array laser comprises emitting units arranged in an array; the emission lens group is used for projecting the signal light onto a target object after the signal light is collimated; the receiving lens group is used for receiving the echo of the diffuse reflection of the target object and converging the echo; the area array detector is used for receiving the echo subjected to the convergence processing by the receiving lens group; the area array laser comprises receiving units arranged in an array; the optical switch is arranged between the receiving lens group and the area array detector and comprises switch subunits arranged in an array; wherein, the corresponding proportional relation of the transmitting unit and the receiving unit is M: 1, M is a positive integer and M > 1; the corresponding proportional relation of the transmitting unit and the switch subunit is N: 1, N is a positive integer and N is less than or equal to M; when the transmitting unit transmits the signal light, the switch subunit corresponding to the transmitting unit is set to be in a light-transmitting state, and other switch subunits are set to be in a light-tight state. According to the arrangement, the plurality of transmitting units correspond to one receiving unit, the number of the point clouds received by one receiving unit 141 is changed from one point cloud to M point clouds, the density of the point clouds is increased under the condition that the angle is not changed, and the resolution ratio of the solid-state laser radar system is further improved; when the transmitting unit transmits the signal light, the on-off state of the switch subunit is controlled, so that only the corresponding region of the receiving unit receives the echo of the signal light, and other regions can not receive the echo of the signal light, thereby reducing the overall intensity of the ambient light, reducing the interference of the ambient light on the signal light, and improving the signal-to-noise ratio and the detection distance.

The solid-state lidar system and the vehicle provided by the embodiment of the disclosure are exemplarily described below with reference to fig. 1 to 10.

Fig. 1 is a schematic structural diagram of a solid-state lidar system according to an embodiment of the present disclosure, fig. 2 is a schematic structural diagram of an area array laser according to an embodiment of the present disclosure, and fig. 3 is a schematic structural diagram of an area array detector according to an embodiment of the present disclosure. Referring to fig. 1-3, the solid state lidar system 100 includes: an area array laser 110 for emitting signal light; the area array laser 110 includes emitting units 111 arranged in an array; an emission lens group 120 for collimating the signal light and projecting the collimated signal light onto the target object 200; the receiving lens group 130 is used for receiving the echo diffusely reflected by the target object 200 and converging the echo; an area array detector 140 for receiving the echo converged by the receiving lens group 130; the area array laser 140 includes receiving units 141 arranged in an array; the optical switch 150 is arranged between the receiving lens group 130 and the area array detector 140, and comprises switch subunits 151 arranged in an array; wherein, the corresponding proportional relationship between the transmitting unit 111 and the receiving unit 141 is M: 1, M is a positive integer and M > 1; the corresponding proportional relationship between the emitting unit 111 and the switch subunit 151 is N: 1, N is a positive integer and N is less than or equal to M; when the transmitting unit 111 transmits the signal light, the corresponding switch subunit 151 is set to the light-transmitting state, and the other switch subunits 151 are set to the light-non-transmitting state.

The area array laser 110 includes i × j emitting units 111 arranged in an array, i represents a row number, j represents a column number, and i and j are positive integers greater than 1; arranging an emission lens group 120 on the light emitting side of the area array laser 110, collimating the signal light emitted by the area array laser 110 by the emission lens group 120, adjusting the light path direction of the signal light, and projecting the adjusted signal light to a target area; through circuit design, the emission unit 111 is controlled to emit signal light according to a preset light emitting time sequence, and due to different distribution positions of the emission unit 11 on the area array laser 110, the signal light is projected to different positions of a target area through the emission lens group, so that the target area is scanned. (ii) a Each emission unit 111 includes a plurality of multi-luminous points, and luminous points in each emission unit 111 simultaneously emit signal light. The area array detector 140 includes k × l receiving units 141 arranged in an array; k represents the number of rows, l represents the number of columns, and k and l are both positive integers greater than 1; each receiving unit 141 includes a number of photodiodes. There is a corresponding relationship between the emitting unit 111 and the receiving unit 141, and M (M > 1) emitting unit 111 corresponds to one receiving unit 141, that is, one receiving unit 141 can receive echoes of signal light emitted by M emitting units 111, so that the number of point clouds received by one receiving unit 141 is changed from one point cloud to M point clouds, which is equivalent to increasing the density of the point clouds under the condition of unchanged angle, thereby improving the resolution of the solid-state lidar system.

Exemplarily, as shown in fig. 4, a schematic structural diagram of a corresponding relationship between a transmitting unit and a receiving unit is provided in the embodiment of the present disclosure. Referring to fig. 4, four transmitting units 111 correspond to one receiving unit 141, that is, echoes of signal light transmitted by one transmitting unit 111 are received by one quarter of the area of the receiving unit 141, and thus, the number of point clouds received by one receiving unit 141 is changed from one point cloud to 2 × 2 point clouds, so that the angular resolutions in the horizontal and vertical directions are increased by two times, respectively.

The optical switch 150 includes switch subunits 151 arranged in an array, the operating state of the switch subunits 151 includes a transparent state and a non-transparent state, and the state of the switch subunits 151 is controlled by a preset logic condition; the switch subunit 151 and the transmitting unit 111 also have a corresponding relationship, and N (N is more than or equal to 1 and N is less than or equal to M) transmitting units 111 correspond to one receiving unit 141; when one transmitting unit 111 transmits signal light, the switch subunit 151 corresponding to the transmitting unit 111 is set to be in a light-transmitting state, and the other switch subunits 151 are set to be in a light-tight state; with such an arrangement, the signal light emitted by the emitting unit 111 is diffusely reflected by the target object 200, and the echo of the reflected signal light passes through the switch subunit 151 in the transparent state and is received by the receiving unit 141 arranged behind the switch subunit; since N is less than or equal to M, a single switch subunit 151 only corresponds to a partial region of one receiving unit 141, so that the influence range of ambient light is reduced, and the overall intensity of the ambient light is reduced, thereby reducing the interference of the ambient light on signal light, and further improving the signal-to-noise ratio and the detection distance.

Exemplarily, as shown in fig. 5, a schematic structural diagram of a corresponding relationship between an emission unit and an optical switch is provided for the embodiment of the present disclosure. Referring to fig. 5, the corresponding proportional relationship between the transmitting unit 111 and the switch subunit 151 is 2:1, i.e. two transmitting units 111 correspond to one switch subunit 151; with reference to fig. 4, four transmitting units 111 correspond to one receiving unit 141, and thus, one switching subunit 151 corresponds to one-half receiving unit 141; when one transmitting unit 111 transmits signal light, the switch subunit 151 corresponding to the transmitting unit 111 is set to be in a light-transmitting state, the reflected echo is only received by one-half area of the receiving unit 141, and the other one-half area is not influenced by the ambient light, so that the influence range of the ambient light is reduced, the overall intensity of the ambient light is reduced, the interference of the ambient light on the signal light is reduced, and the signal-to-noise ratio and the detection distance are further improved.

It can be understood that fig. 4 only exemplarily shows that the corresponding ratio of the transmitting unit 111 to the receiving unit 141 is 4:1, and fig. 5 only exemplarily shows that the corresponding ratio of the transmitting unit 111 to the switch subunit 151 is 2:1, but does not constitute a limitation to the solid-state lidar system provided by the embodiment of the present disclosure. In other embodiments, the corresponding proportional relationship between the transmitting unit 111 and the receiving unit 141 and the corresponding proportional relationship between the transmitting unit 111 and the switch subunit 151 may be set according to the requirements of the solid-state lidar system, and are not limited herein.

The disclosed embodiment provides a solid-state lidar system 100, including: an area array laser 110 for emitting signal light; the area array laser 110 includes emitting units 111 arranged in an array; the emission lens group 120 is configured to collimate the signal light and irradiate the signal light onto the target object 200; the receiving lens group 130 is used for receiving the echo diffusely reflected by the target object 200 and converging the echo; the area array detector 140 is configured to receive the echo subjected to the convergence processing by the receiving lens group 130; the area array laser 140 includes receiving units 141 arranged in an array; and an optical switch 150, disposed between the receiving lens group 130 and the area array detector 140, including a switch subunit 151 arranged in an array; wherein, the corresponding proportional relationship between the transmitting unit 111 and the receiving unit 141 is M: 1, M is a positive integer and M > 1; the corresponding proportional relationship between the emitting unit 111 and the switch subunit 151 is N: 1, N is a positive integer and N is less than or equal to M; when the transmitting unit 111 transmits the signal light, the corresponding switch subunit 151 is set to the light-transmitting state, and the other switch subunits 151 are set to the light-non-transmitting state. With such an arrangement, the plurality of transmitting units 111 correspond to one receiving unit 141, and the number of point clouds received by one receiving unit 141 is changed from one point cloud to M point clouds, so that the density of the point clouds is increased under the condition that the angle is not changed, and the resolution of the solid-state laser radar system 100 is further improved; when the transmitting unit 111 transmits the signal light, the switch state of the switch subunit 151 is controlled, so that only the corresponding region of the receiving unit 141 receives the echo, and other regions do not receive the echo, thereby reducing the overall intensity of the ambient light, reducing the interference of the ambient light on the signal light, and improving the signal-to-noise ratio and the detection distance.

In one embodiment, the range of values of M includes at least one of 4, 9, and 16.

The value range of M is at least one of 4, 9 and 16, the corresponding proportion relation between the transmitting unit and the receiving unit is 4:1, 9:1 and 16:1, so that the echo of the signal light transmitted by one transmitting unit is received by a quarter, a ninth and a sixteenth area of one receiving unit, and thus, the number of the point clouds received by one receiving unit is changed from one point cloud to 2 x 2, 3 x 3 and 4 x 4 point clouds, the angular resolution in the horizontal direction and the vertical direction is increased by two times, three times and four times respectively, and the uniform symmetry of the angular resolution in the horizontal direction and the vertical direction is ensured.

In one embodiment, in a solid state lidar system, N is equal to 1.

Wherein, N is equal to 1, which indicates that the corresponding proportional relation between the emission unit and the optical switch subunit is 1: 1; namely, the emission units correspond to the optical switch subunits one by one; because the corresponding proportional relation M exists between the transmitting unit and the receiving unit: 1, M is a positive integer and M > 1, then the corresponding proportional relationship between the optical switch subunit and the receiving unit is also M: 1. when one transmitting unit transmits signal light, the switch subunit corresponding to the transmitting unit is set to be in a light-transmitting state, and other switch subunits are set to be in a light-tight state; therefore, the optical switch subunit in the light-transmitting state only corresponds to the M-th area of the receiving unit, the echo of the signal light cannot be received by other areas of the receiving unit, and the overall intensity of the ambient light is reduced, so that the interference of the ambient light on the signal light is reduced, the signal-to-noise ratio is improved, and the detection distance is further improved.

In one embodiment, the area array Laser includes a Vertical Cavity Surface Emitting Laser (VCSEL); and/or the area array detector comprises a Silicon Photomultiplier (SiPM) array detector.

The vertical cavity surface emitting laser is a semiconductor laser with a novel structure and is developed on the basis of gallium arsenide semiconductor materials. Compared with the conventional emission laser, the vertical cavity surface emitting laser has the following advantages: (1) the optical fiber has a small original field divergence angle, emits a narrow and round light beam, and is easy to couple with an optical fiber; (2) the threshold current is low; (3) the modulation frequency is high; (4) the single longitudinal and transverse mode works in a wide temperature and current range; (5) the process manufacturing and detection can be completed without cleavage, and the cost is low; (6) and large-scale array and photoelectric integration are easy to realize.

The SiPM array detector is a solid-state high-gain radiation detector, can generate output current pulses after absorbing photons, has single photon sensitivity, and can detect the wavelength of light from near ultraviolet to near infrared; at the same time, SiPM array detectors are compact devices that can withstand mechanical shock. The SiPM array detector comprises k multiplied by l SiPM units arranged in an array, wherein k represents the number of rows, l represents the number of columns, and both k and l are positive integers larger than 1; each SiPM cell includes a number of Single Photon Avalanche Diodes (SPADs).

In one embodiment, the emission unit emits the signal light according to a preset light emission timing.

Specifically, the emission unit is controlled to emit signal light according to a preset light emission timing through circuit design; the emission unit emits signal light, changes the direction of a light path after passing through the emission lens group and is projected to different positions of a target area due to different distribution positions of the emission unit on the area array laser; the emission unit emits signal light according to a preset light-emitting time sequence, the emission lens group sequentially adjusts the light path direction of the signal light emitted by the emission unit by utilizing the time difference of the signal light emitted by each emission unit and projects the signal light to different positions of a target area, so that the target area is scanned.

In one embodiment, the optical switch comprises at least one of a reflective optical switch and a transmissive optical switch.

Optical switches include, but are not limited to, Mechanical optical switches, thermo-optical switches, acousto-optic switches, Electro-optic switches, magneto-optic switches, liquid crystal optical switches, and Micro-Electro-Mechanical systems (MEMS) optical switches; the optical switch can be classified into a reflective optical switch and a transmissive optical switch according to a propagation path of a signal light echo reflected by a target object at the optical switch.

The working state of the reflective optical switch comprises a light transmitting state and a light non-transmitting state, and when the reflective optical switch is in the light transmitting state, the optical switch closes a shading structure between the signal light echo and the area array detector, so that the signal light echo can be received by the area array detector through the optical switch; when the reflective optical switch is in a light-tight state, the optical switch opens the light-shielding structure between the signal light echo and the area array detector, and reflects the signal light echo irradiated on the optical switch, so that the signal light echo can not be received by the area array detector.

The working state of the transmission type optical switch comprises a light transmission state and a light non-transmission state, when the transmission type optical switch is in the light transmission state, the optical switch can be penetrated by the echo of the signal light, the echo of the signal light is transmitted at the optical switch and is received by an area array detector arranged behind the optical switch; when the transmission-type optical switch is in a light-tight state, the optical switch is light-tight, and the echo of the signal light is blocked at the light-open position and cannot be received by the area array detector.

In one embodiment, the reflective optical switch is configured as a Digital Micromirror Device (DMD), which includes an array of mirrors.

The digital micromirror device comprises a plurality of small aluminum reflectors which are arranged in an array, and the reflectors have high reflectivity; each mirror can be rotated around its central axis by a certain angle, as shown in fig. 6, which provides a schematic diagram of different states of the mirror in the digital micromirror device according to the embodiment of the present disclosure. Referring to fig. 6, when the rotation angle of the mirror is 0 °, that is, the mirror does not rotate, the mirror surface of the mirror faces and is parallel to the receiving lens group, the echo of the signal light passes through the receiving lens group and then irradiates on the mirror surface of the mirror, and is then reflected by the mirror surface and cannot be received by the area array laser, and at this time, the mirror is in a non-transparent state; when the rotation angle of the reflector is 90 degrees, the mirror surface of the reflector is perpendicular to the receiving lens group, the projection in the direction perpendicular to the receiving lens group is a line and is superposed with the projection of the central shaft, a hole is formed at the corresponding position of the reflector, the echo of the signal light is received by the area array detector through the hole, and the reflector is in a light transmission state at the moment.

Illustratively, as shown in fig. 7, a schematic diagram of an operating principle of a solid-state lidar to which a digital micromirror device is applied is provided for an embodiment of the present disclosure. Referring to fig. 7, in the solid-state lidar system, the corresponding proportional relationship between the transmitting unit 111 and the receiving unit 141 is 4:1, and the corresponding proportional relationship between the transmitting unit 111 and the mirror is 1: 1, namely, four transmitting units 111 correspond to one receiving unit 141, and the transmitting units 111 correspond to the reflecting mirrors one by one, so that four reflecting mirrors correspond to one receiving unit; assuming that the four transmitting units 111 sequentially transmit signal light in the order from left to right and from top to bottom (i.e., top left → top right → bottom left → bottom right), the rotation angles of the mirrors corresponding thereto are sequentially controlled to be 90 ° in the above order, and the rotation angles of the other three mirrors are controlled to be 0 °; the method specifically comprises the following steps: (a) when the transmitting unit 111 at the upper left corner transmits signal light, the reflector at the upper left corner corresponding to the transmitting unit is controlled to rotate by 90 degrees, the other three reflectors do not rotate, only the quarter area at the upper left corner of the receiving unit 141 can receive signal light echoes, and the other areas cannot receive signal light echoes; (b) when the transmitting unit 111 at the upper right corner transmits signal light, the reflector at the upper right corner corresponding to the transmitting unit is controlled to rotate by 90 degrees, the other three reflectors do not rotate, only the quarter area at the upper right corner of the receiving unit 141 can receive signal light echoes, and the other areas cannot receive signal light echoes; (c) when the transmitting unit 111 at the lower left corner transmits signal light, the corresponding reflector at the lower left corner is controlled to rotate by 90 degrees, the other three reflectors do not rotate, only one quarter of the area at the lower left corner of the receiving unit 141 can receive signal light echoes, and the other areas cannot receive signal light echoes; (d) when the transmitting unit 111 at the lower right corner transmits the signal light, the corresponding reflector at the lower right corner is controlled to rotate by 90 degrees, the other three reflectors do not rotate, only one quarter of the area at the lower right corner of the receiving unit 141 can receive the signal light echo, and the other areas cannot receive the signal light echo; therefore, the purpose of reducing the ambient light interference can be achieved.

In one embodiment, the transmissive optical switch is configured as a liquid crystal optical switch including an array of liquid crystal optical switch subunits.

The liquid crystal optical switch utilizes the characteristic that liquid crystal molecules have birefringence effect, and the liquid crystal molecules are distributed randomly and in a scattering state when no voltage is applied, and at the moment, the liquid crystal optical switch is in a light-tight state; the refractive index and the polarization state of the light are changed by the external voltage, the transmittance of the light is changed by changing the direction of the liquid crystal molecules, the long axes of the liquid crystal molecules are distributed along the direction of the electric field, the refractive index is uniform, the transparent state is presented, and at the moment, the liquid crystal light switch is in the transparent state.

The liquid crystal optical switch includes a plurality of liquid crystal optical switch subunits arranged in an array, as shown in fig. 8, which is a schematic diagram of different states of the liquid crystal optical switch subunits in the liquid crystal optical switch provided in the embodiment of the present disclosure. Referring to fig. 8, the arrangement state of the liquid crystal molecules in the liquid crystal optical switch subunit is changed by controlling the applied voltage of the liquid crystal optical switch subunit, so as to control the working state of the liquid crystal optical switch subunit to be transparent or opaque, and correspondingly, the signal light echo can be transmitted or not transmitted through the liquid crystal optical switch subunit, thereby achieving the switching effect.

Exemplarily, as shown in fig. 9, a schematic diagram of an operating principle of a solid-state lidar to which a liquid crystal optical switch is applied is provided for the embodiment of the present disclosure. Referring to fig. 9, in the solid-state lidar system, the ratio relationship between the transmitting unit 111 and the receiving unit 141 is 4:1, and the ratio relationship between the transmitting unit 111 and the liquid crystal optical switch subunit is 1: 1, that is, four transmitting units 111 correspond to one receiving unit 141, and the transmitting units 111 correspond to the liquid crystal optical switch subunits one to one, so that the four liquid crystal optical switch subunits correspond to one receiving unit; assuming that the four emitting units 111 sequentially emit signal light from left to right and from top to bottom (i.e. top left → top right → bottom left → bottom right), the liquid crystal optical switch sub-units corresponding to the four emitting units are sequentially controlled to be in a transparent state and the other three liquid crystal optical switch sub-units are controlled to be in a non-transparent state; the method specifically comprises the following steps: (a) when the transmitting unit 111 at the upper left corner transmits signal light, the liquid crystal optical switch subunit at the upper left corner corresponding to the transmitting unit is controlled to be in a light transmitting state, the other three liquid crystal optical switch subunits are in a light non-transmitting state, only one quarter of the area at the upper left corner of the receiving unit 141 can receive signal light echoes, and the other areas cannot receive signal light echoes; (b) when the transmitting unit 111 at the upper right corner transmits signal light, the liquid crystal optical switch subunit at the upper right corner corresponding to the transmitting unit 111 is controlled to be in a light transmitting state, the other three liquid crystal optical switch subunits are in a light non-transmitting state, only one quarter of the area at the upper right corner of the receiving unit 141 can receive signal light echoes, and the other areas cannot receive signal light echoes; (c) when the transmitting unit 111 at the lower left corner transmits signal light, the liquid crystal optical switch subunit at the lower left corner corresponding to the transmitting unit is controlled to be in a light transmitting state, the other three liquid crystal optical switch subunits are in a light non-transmitting state, only one quarter of the area at the lower left corner of the receiving unit 141 can receive signal light echoes, and the other areas cannot receive signal light echoes; (d) when the transmitting unit 111 at the lower right corner transmits signal light, the liquid crystal optical switch subunit at the lower right corner corresponding to the transmitting unit is controlled to be in a light transmitting state, the other three liquid crystal optical switch subunits are in a light non-transmitting state, only one quarter of the area at the lower right corner of the receiving unit 141 can receive signal light echoes, and the other areas cannot receive signal light echoes; therefore, the purpose of reducing the ambient light interference can be achieved.

In one embodiment, as shown in fig. 10, a schematic structural diagram of another solid-state lidar system provided for embodiments of the present disclosure is shown. Referring to fig. 10, solid-state lidar system 100 further includes: an optical filter 160; the filter 160 is disposed between the receiving lens group 130 and the object 200, and is configured to transmit light beams within the same wavelength range as the signal light emitted by the area array laser 110.

By utilizing the characteristic of the optical filter having a selected waveband, the optical filter 160 is disposed between the receiving lens assembly 130 and the target object 200, the optical filter 160 only allows light rays with the same waveband range as that of the signal light emitted by the area array laser 110 to pass through, and most of light rays with other wavebands are absorbed by the optical filter 160, so that the optical filter 160 can filter out ambient light with a waveband range different from that of the signal light, thereby further reducing the interference of the ambient light.

On the basis of the above embodiment, the embodiment of the present disclosure further provides a vehicle, including: any solid-state laser radar system has corresponding beneficial effects, and is not described herein again in order to avoid repeated description.

It should be noted that, in other embodiments, the vehicle further includes other vehicle-mounted sensor systems known to those skilled in the art, such as a camera, a millimeter wave radar, a navigation positioning device, and the like, which are not limited herein.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present disclosure, which enable those skilled in the art to understand or practice the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A solid state lidar system, comprising:

an area array laser for emitting signal light; the area array laser comprises emitting units arranged in an array;

the emission lens group is used for projecting the signal light onto a target object after the signal light is collimated;

the receiving lens group is used for receiving the echo of the diffuse reflection of the target object and carrying out convergence processing on the echo;

the area array detector is used for receiving the echo subjected to the convergence processing by the receiving lens group; the area array laser comprises receiving units arranged in an array;

the optical switch is arranged between the receiving lens group and the area array detector and comprises switch subunits arranged in an array;

wherein, the corresponding proportional relation of the transmitting unit and the receiving unit is M: 1, M is a positive integer and M > 1; the corresponding proportional relation between the transmitting unit and the switch subunit is N: 1, N is a positive integer and N is less than or equal to M; when the transmitting unit transmits signal light, the switch subunits corresponding to the transmitting unit are set to be in a light-transmitting state, and other switch subunits are set to be in a light-tight state.

2. The solid state lidar system of claim 1, wherein the area array laser comprises a vertical cavity surface emitting laser;

and/or the area array detector comprises a silicon photomultiplier array detector.

3. The solid-state lidar system according to claim 2, wherein the transmitting unit transmits the signal light according to a preset light emission timing.

4. The solid state lidar system of claim 1, wherein the optical switch comprises at least one of a reflective optical switch and a transmissive optical switch.

5. The solid state lidar system of claim 4, wherein the reflective optical switch is configured as a digital micromirror device comprising an array of mirrors.

6. The solid state lidar system of claim 4, wherein the transmissive optical switch is configured as a liquid crystal optical switch comprising an array of liquid crystal optical switch subunits.

7. The solid state lidar system of claim 1, wherein N is equal to 1.

8. The solid state lidar system of claim 1, wherein M has a range of values that includes at least one of 4, 9, and 16.

9. The solid state lidar system of any of claims 1-8, further comprising: an optical filter;

the optical filter is arranged between the receiving lens group and the target object and is used for transmitting light rays with the same wave band range as the signal light emitted by the area array laser.

10. A vehicle, characterized by comprising: the solid state lidar system of any of claims 1-9.

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