CN207074262U - Laser radar and its two dimensional phased battle array laser emission element - Google Patents

Abstract

The utility model relates to a laser radar and a two-dimensional phased array laser emitting unit thereof. The two-dimensional phased array laser emitting unit includes a laser beam splitting component, a plurality of light emitting antennas distributed in a matrix and a plurality of phase adjusters. Multiple laser beams can be emitted through the cooperation of laser beam splitting components and multiple light emitting antennas. Moreover, adjusting the phase of the multiple laser beams through the phase adjuster can make the multiple laser beams have a fixed phase difference, so that the radiation pattern can be obtained through interference in the far field, so as to form the strongest main beam in a specific direction and realize scanning. Furthermore, changing the phase of multiple lasers can obtain different radiation patterns, thereby realizing omni-directional scanning. LiDAR thus enables omnidirectional monitoring without the need for mechanically rotating parts. Moreover, the scanning speed of the lidar is determined by the frequency of the phase adjustment, so the scanning speed of the lidar is also faster. Therefore, the above-mentioned lidar and its two-dimensional phased array laser emission unit have a smaller volume and a higher scanning rate.

Description

LiDAR and its two-dimensional phased array laser emitting unit

technical field

The utility model relates to the technical field of laser detection, in particular to a laser radar and a two-dimensional phased array laser emitting unit thereof.

Background technique

Lidar is a sensor that uses laser light to detect and measure distances. Its principle is similar to that of ordinary sonic radar and sonar. That is, the laser pulse is emitted to the target by the transmitting device, and the distance and reflectivity of the target are measured by the receiving device measuring the delay and intensity of the return pulse.

In order to achieve all-round monitoring, the radar needs to scan 360-degree space. Traditional radar generally adopts a mechanical drive mode, that is, a mechanical device drives the radar's transmitting unit to rotate in all directions to achieve 360-degree scanning. However, such radars use cumbersome mechanisms that make scanning rates slow. Moreover, once the mechanical rotating device breaks down, it is difficult to continue to use normally.

Similar to traditional ordinary radars, lidars currently on the market also use mechanical rotation to perform 360-degree spatial scanning. This has caused lidar, like traditional radar, to have the disadvantages of large size, slow scanning, high price, and difficulty in normal use after mechanical device failure, which is not conducive to large-scale use in the field of consumer electronics.

Utility model content

Based on this, it is necessary to provide a laser radar with a smaller volume and a higher scanning rate and its two-dimensional phased array laser emitting unit for the problems of large volume and slow scanning of the existing laser radar.

A two-dimensional phased array laser emitting unit, comprising:

A laser beam splitting component, including a light incident end and a plurality of light output ends, the laser beams are respectively emitted from the plurality of light output ends after being incident on the light input end, so as to obtain multiple laser beams;

A plurality of light-emitting antennas for emitting the multi-path lasers, the plurality of light-emitting antennas respectively cooperate with the plurality of light-emitting ends to form a plurality of laser light paths connected in parallel and for the transmission of the multi-path lasers , the multiple optical transmitting antennas are distributed in an NxM matrix, where M and N are both integers greater than or equal to 2; and

A plurality of phase adjusters, each of which is used to adjust the phase of the multiple laser beams on the corresponding laser light path.

In one of the embodiments, the laser beam splitting component includes 1 to N optical couplers and N 1 to M optical couplers, wherein the incident end of the 1 to N optical couplers is used as the light incident end, The output ends of the 1 to M optical couplers are used as the light output ends, and the input ends of the N number of 1 to M optical couplers are connected to the output ends of the 1 to N optical couplers respectively.

In one of the embodiments, the 1 to M optical couplers and the 1 to N optical couplers are edge couplers or grating couplers.

In one of the embodiments, the multiple phase adjusters are respectively arranged on the multiple laser optical paths.

In one of the embodiments, the phase adjustment of the laser light paths corresponding to the light emitting antennas located in the same row or column of the NxM matrix is implemented by the synchronized phase adjuster.

In one of the embodiments, the phase adjustment of the laser light paths corresponding to the light emitting antennas located in the same row or column of the NxM matrix is implemented by the same phase adjuster.

In one of the embodiments, the light emitting antenna is a grating coupler.

In one embodiment, the phase adjuster includes an optical waveguide and a micro heater for heating the optical waveguide, and the optical waveguide is located on the laser optical path.

In one embodiment, the phase adjuster includes a Pn node and a voltage regulator for adjusting the voltage across the Pn node, and the Pn node is located on the laser optical path.

A laser radar, is characterized in that, comprises:

The two-dimensional phased array laser emitting unit as described in any one of the above preferred embodiments;

The echo receiving unit is used to receive the echo signal generated by the main beam of radiation formed by the interference of the multi-channel laser in the far field and reflected by the target object; and

A processor communicatively connected with the two-dimensional phased array laser emitting unit and the echo receiving unit.

The above-mentioned laser radar and its two-dimensional phased array laser emitting unit can emit multiple laser beams by cooperating with a plurality of light emitting antennas through a laser beam splitting component. Moreover, the adjustment of the phase adjuster can make the multi-channel laser have a fixed phase difference, so that the radiation pattern can be obtained through interference in the far field, so as to form the strongest main beam in a specific direction and realize scanning. Furthermore, the phase change of multiple laser beams can obtain different radiation patterns in the far field, so that the direction of the strongest main beam can be dynamically adjusted, and finally realize omni-directional scanning. Therefore, lidar can realize omni-directional monitoring without mechanical rotating parts, which is beneficial to reduce the size. Furthermore, the scanning speed of the lidar is determined by the frequency of the phase adjustment, and is not limited by the rotation speed of the mechanical rotating parts, so the scanning speed of the lidar is also faster. Therefore, the above-mentioned lidar and its two-dimensional phased array laser emission unit have a smaller volume and a higher scanning rate.

Description of drawings

Fig. 1 is the module schematic diagram of laser radar in the preferred embodiment of the present utility model;

FIG. 2 is a schematic structural diagram of a two-dimensional phased array laser emitting unit in the lidar shown in FIG. 1 .

Detailed ways

In order to facilitate the understanding of the utility model, the utility model will be described more fully below with reference to the relevant drawings. Preferred embodiments of the present utility model are provided in the accompanying drawings. However, the invention can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present utility model more thorough and comprehensive.

It should be noted that when an element is referred to as being “fixed” to another element, it can be directly on the other element or there can also be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and similar expressions are used herein for purposes of illustration only.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of this invention. The terminology used in the description of the utility model herein is only for the purpose of describing specific embodiments, and is not intended to limit the utility model. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Please refer to FIG. 1 , the laser radar 10 in the preferred embodiment of the present invention includes a two-dimensional phased array laser emitting unit 100 , an echo receiving unit 101 and a processor 102 .

The two-dimensional phased array laser emitting unit 100 is used to emit multiple laser beams, and the laser beams can generate echo signals after being reflected by objects.

Specifically, the multiple paths of light emitted by the phased array laser emitting unit 100 are coherent (same frequency and fixed phase difference). Therefore, multiple lasers can form a specific radiation pattern after far-field interference. That is, there will be a strongest main beam in a certain direction, and other weaker secondary beams will be emitted in other directions. The primary and secondary beams are not parallel but at corresponding angles. When the laser radar 10 is in use, the collected echo signal is the signal obtained after the main beam encounters the reflection of the target object.

The echo receiving unit 101 is used for receiving echo signals. The processor 102 processes and analyzes the echo signal, so as to obtain parameters such as the shape and distance of the target object.

Please also refer to FIG. 2 , the present invention also provides a two-dimensional phased array laser emitting unit 100 , including a laser beam splitting component 110 , a light emitting antenna 120 and a phase adjuster 130 .

The laser beam splitting component 110 includes a light incident end and a plurality of light output ends. The laser beam is incident on the light incident end and exits from multiple light output ends respectively to obtain multiple laser beams. When the laser radar 10 is working, the laser beam emitted by the laser light source 20 enters the laser beam splitting assembly 110 from the light incident end, and finally exits from the light output end to obtain multiple laser signals with the same power (that is, "multiple lasers").

More than 120 light emitting antennas. Wherein, a plurality of optical transmitting antennas are distributed in an NxM matrix, and both M and N are integers greater than or equal to 2. A plurality of light emitting antennas 120 cooperate with a plurality of light emitting ends respectively to form a plurality of parallel laser light paths for multi-path laser transmission. Specifically, the light emitting end and the light emitting antenna 120 may communicate through an optical waveguide, so as to realize the transmission of light beams between the two. Wherein, the optical waveguide may be silicon, optical fiber, or the like. Therefore, the multiple laser signals sent out from the light emitting end can enter the light emitting antenna 120 and be further emitted into the space by the plurality of light emitting antennas 120 .

Since multiple laser light paths are connected in parallel, each laser light path is relatively independent. Even if one of the laser optical paths (the optical transmitting antenna 120 or the optical waveguide connected to the optical transmitting antenna 120) fails, it will not affect the remaining laser optical paths. Therefore, the function of the two-dimensional phased array laser emitting unit 100 can still be normally implemented when a partial failure occurs, thereby improving the reliability of the laser radar 10 .

There are multiple phase adjusters 130 . Wherein, each phase adjuster 130 is used to adjust the phase of multiple laser beams on the corresponding laser optical path. The phase adjuster 130 and the laser light path can be one-to-one, or one-to-many.

The multiple laser signals emitted by multiple light emitting antennas 120 interfere with each other in the far field, thereby forming the strongest beam in a specific direction, and realizing scanning in a specific range. The direction of the strongest beam obtained by the mutual interference of multiple laser signals is related to the phase of each laser signal. Therefore, the phase adjuster 130 adjusts the phases of the multiple lasers separately according to preset rules, so that the multiple lasers can obtain different scanning ranges through interference in the distance, so that the scanning range is dynamic, thereby realizing omni-directional scanning.

Further, the scanning rate of the laser radar 10 is determined by the phase adjustment frequency of the phase adjuster 130 , and is not limited by the rotation speed of the mechanical rotating parts. The speed of the phase adjustment can be controlled by the circuit, and the response is fast, so the scanning speed of the laser radar 10 is also faster.

In this embodiment, multiple phase adjusters 130 are respectively arranged on multiple laser optical paths.

Each laser light path corresponds to a phase adjuster 130, that is, the phase adjuster 130 is one-to-one with the laser light path. Therefore, the phases of the laser signals transmitted through each laser optical path can be individually adjusted without affecting each other.

In this embodiment, the phase adjustment of the laser light paths corresponding to the light emitting antennas 120 located in the same row or column of the NxM matrix is implemented by the synchronous phase adjuster 130 .

Specifically, the laser optical path whose phase is adjusted by the synchronous phase adjuster 130 is called a synchronous laser optical path. Wherein, the synchronous laser optical path refers to a plurality of laser optical paths transmitting laser signals with the same phase, and the phases of the corresponding laser signals emitted by the optical transmitting antenna 120 are also the same. Specifically, in this embodiment, the light emitting antennas 120 corresponding to the synchronous laser light paths are located in the same column of the NxM matrix. By synchronously controlling the laser signals emitted by the light emitting antennas 120 on the same row or column, the amount of computation can be reduced while meeting the scanning requirements of the laser radar 10 .

In another embodiment, the same phase adjuster 130 implements phase adjustment for the laser light paths corresponding to the light transmitting antennas located in the same row or column of the NxM matrix.

Specifically, the same phase adjuster 130 implements multiple optical paths for phase adjustment to form the same synchronous laser optical path as in the previous embodiment. The difference is that the synchronous laser optical route in the previous embodiment realizes phase adjustment through a plurality of synchronous phase adjusters 130, while the synchronous laser optical route in this embodiment realizes phase adjustment through the same phase adjuster 130, that is, the phase adjuster 130 and the laser light path are one-to-many.

Further, a unified phase adjuster 130 can be arranged on the same column or row, so as to realize the phase adjustment of the laser signal in the laser light path on the corresponding row or column respectively. By using the same phase adjuster 130 to synchronously control the phases of the laser signals emitted by the light emitting antennas 120 on the same column or row, the performance of the laser radar 10 can meet the requirements. At the same time, the structure can be effectively simplified.

When the laser radar 10 scans, the light emitting antennas 120 in the same column in the synchronous laser light path emit laser signals with the same phase. The light emitting antennas 120 on other columns can emit laser signals of different phases (as shown in FIG. 2 , φ ₁ , φ ₂ , φ ₃ , . . . , φ _M ). By controlling the phase adjuster 130, the phases of the laser signals emitted by the light emitting antennas 120 of different columns are switched, so that a dynamic scanning range is generated by interference in the far field.

In this embodiment, the laser beam splitting component 110 includes 1 to N optical couplers 111 and N 1 to M optical couplers 113 . Wherein, the incident end of 1 to N optical coupler 111 is used as the light incident end, and the outgoing end of 1 to M optical coupler 113 is used as the light outgoing end, and the incident end of N 1 to M optical coupler 113 is respectively connected with 1 to N The output end of the optical coupler 111 is connected.

Specifically, the function of the 1 to N optical couplers 111 is to equally divide the incident light into N beams of outgoing light, and the function of the 1 to M optical couplers 113 is also the same. After the laser beam emitted by the laser light source 20 is incident through the 1 to N optical coupler 111, N beams of outgoing light are obtained; further, the N beams of outgoing light are respectively incident from the incident ends of N 1 to M optical couplers 113; finally, it is obtained M is multiplied by N beams of laser signals (that is, multiple lasers). Correspondingly, the number of light transmitting antennas 120 is also M times N.

It should be noted that, in other embodiments, the laser beam splitting component 110 may also be composed of multiple beam splitters. Wherein, the multiple optical beam splitters are divided into multiple levels, and the incident end of the optical beam splitter of the next level is connected with the output end of the optical beam splitter of the previous level. The optical beam splitter can be a split-two beam splitter, or other types of beam splitters such as a split-four beam splitter.

In this embodiment, the 1 to N optical couplers 111 and the 1 to M optical couplers 113 are edge couplers or grating couplers.

In this embodiment, the light transmitting antenna 120 is a grating coupler.

Among them, 1 to N optical couplers 111 and 1 to M optical couplers 113, light transmitting antenna 120 and phase regulator 130 can be integrated on the chip, thereby further reducing the number of two-dimensional phased array laser transmitting unit 100 and laser radar 10. volume of. Specifically, the 1-to-N optical couplers 111, 1-to-M optical couplers 113, the optical transmitting antenna 120 and the phase adjuster 130 can be realized on the chip by the "silicon photonic integrated optical circuit technology" compatible with the CMOS process.

In this embodiment, the phase adjuster 130 includes an optical waveguide and a micro heater for heating the optical waveguide, and the optical waveguide is located on the optical path of the laser.

Specifically, the optical waveguide is located on the optical path of the laser, and the multiple laser beams will pass through the optical waveguide during transmission. The phase of laser light propagating in the optical waveguide is determined by its effective refractive index in the optical waveguide. The effective refractive index changes with the temperature of the optical waveguide, that is, the "thermo-optic effect". Therefore, the temperature of the optical waveguide can be changed by using the micro-heater to heat the optical waveguide or stop heating, thereby adjusting the phase of the corresponding multi-channel laser light.

In another embodiment, the phase adjuster 130 includes a Pn node and a voltage regulator for adjusting the voltage across the Pn node, and the Pn node is located on the laser optical path.

Specifically, the effective refractive index is also related to the concentration of carriers (electrons and holes) in the optical waveguide, that is, the "plasmon dispersion effect". Applying different voltages to both ends of the Pn junction can lead to changes in the concentration of carriers in the optical waveguide, thereby changing the effective refractive index, and then changing the phase of the corresponding multi-channel laser.

It should be noted that, in other embodiments, the phase adjustment manners of the phase adjuster 130 are not limited to the above two.

The above-mentioned laser radar 10 and its two-dimensional phased array laser emitting unit 100 can emit multiple laser beams by cooperating with a plurality of light emitting antennas 120 through a laser beam splitting component 110 . Moreover, the adjustment by the phase adjuster 130 can make the multiple laser beams have a fixed phase difference, so that the radiation pattern can be obtained through interference in the far field, so as to form the strongest main beam in a specific direction and realize scanning. Furthermore, the phase change of multiple laser beams can obtain different radiation patterns in the far field, so that the direction of the strongest main beam can be dynamically adjusted, and finally realize omni-directional scanning. Therefore, the laser radar 10 can realize all-round monitoring without mechanical rotating parts, which is beneficial to reduce the volume. Furthermore, the scanning speed of the laser radar 10 is determined by the frequency of the phase adjustment, and is not limited by the rotation speed of the mechanical rotating parts, so the scanning speed of the laser radar 10 is also faster. Therefore, the above-mentioned laser radar 10 and its two-dimensional phased array laser emitting unit 100 have a smaller volume and a higher scanning rate.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the utility model, and the description thereof is relatively specific and detailed, but it should not be understood as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the scope of protection of the utility model patent should be based on the appended claims.

Claims (10)

1. A kind of 1. two dimensional phased battle array laser emission element, it is characterised in that including：

   Laser beam splitter component, including light incident side and multiple light exit sides, laser beam are distinguished after the light incident side incidence It is emitted from the multiple light exit side, to obtain multi-path laser；

   Multiple light transmitting antennas for being used to launch the multi-path laser, the multiple smooth transmitting antenna go out with the multiple light respectively Penetrate end to coordinate, to form laser optical path that is multiple parallel with one another and transmitting for the multi-path laser, the multiple smooth transmitting antenna In NxM matrix distributions, wherein M, N is the integer more than or equal to 2；And

   Multiple phase regulators, the multichannel that each phase regulator is used to adjust on the corresponding laser optical path swash The phase of light.
2. 2. two dimensional phased battle array laser emission element according to claim 1, it is characterised in that the laser beam splitter component includes 1 to N photo-couplers and N number of 1 arrive M photo-couplers, wherein, described 1 arrives the incidence ends of N photo-couplers as the light incident side, Described 1 to M photo-couplers exit end as the light exit side, and N number of described 1 to M photo-couplers incidence end respectively with The output end of described 1 to N photo-couplers connects.
3. 3. two dimensional phased battle array laser emission element according to claim 2, it is characterised in that described 1 arrives M photo-couplers and institute State 1 to N photo-couplers be edge couplers or grating coupler.
4. 4. two dimensional phased battle array laser emission element according to claim 1, it is characterised in that the multiple phase regulator point It is not arranged on the multiple laser optical path.
5. 5. two dimensional phased battle array laser emission element according to claim 4, it is characterised in that same positioned at the NxM matrixes The laser optical path corresponding to the smooth transmitting antenna on row or same row, phase is realized by the phase regulator of synchronization Position regulation.
6. 6. two dimensional phased battle array laser emission element according to claim 1, it is characterised in that same positioned at the NxM matrixes The laser optical path corresponding to the smooth transmitting antenna on row or same row, phase is realized by the same phase regulator Position regulation.
7. 7. two dimensional phased battle array laser emission element according to claim 1, it is characterised in that the smooth transmitting antenna is grating Coupler.
8. 8. according to any one of claim 1 to the 7 two dimensional phased battle array laser emission element, it is characterised in that the phase is adjusted It is to include fiber waveguide and the microheater for being heated to the fiber waveguide to save device, and the fiber waveguide is located at the laser In light path.
9. 9. according to any one of claim 1 to the 7 two dimensional phased battle array laser emission element, it is characterised in that the phase is adjusted Section device includes the voltage regulator that Pn is saved and both end voltage is saved for adjusting the Pn, and the Pn sections are located at the laser optical path On.
10. A kind of 10. laser radar, it is characterised in that including：

    Two dimensional phased battle array laser emission element as described in above-mentioned any one of claim 1~9；

    Echo receiving unit, for receiving the multi-path laser to interfere in far field, the radiation main beam to be formed reflects institute through subject matter Caused echo-signal；And

    With the two dimensional phased battle array laser emission element and the processor of Echo receiving unit communication connection.