Laser emission mechanism and phased array laser radar

Abstract

The present invention relates to a laser emitting mechanism and a phased array laser radar. The laser emitting mechanism includes a laser, which is used to generate a laser light source, and the laser is provided with at least one; and a phased array unit, which is provided with at least one phased array unit. The phased array unit is optically connected to the corresponding laser, and the phased array unit is used to receive the laser light source generated by the laser, and to emit the laser light source as a detection laser toward the object to be measured. The phased array laser radar includes the aforementioned laser emitting mechanism; and a laser receiving mechanism. The laser and the phased array unit are matched and set according to the quantity required, and can be used together to perform multi-dimensional scanning, without the need for traditional mechanical rotation devices, with low cost, high measurement reliability, and low failure rate.

Description

Technical Field

[0001] The present invention relates to the technical field of radar detection in automobile driving, and in particular to a laser emitting mechanism and a phased array laser radar. Background Art

[0002] LiDAR is a device that uses lasers for detection and distance measurement. Its principle is similar to radar or sonar, that is, a transmitter emits laser pulses to a target object, and a receiver measures the delay and intensity of the return pulses to measure the distance and reflectivity of the target object.

[0003] Traditional laser radar transmitters usually use mechanical rotating devices to perform 360-degree circular scanning and integrate multiple sets of laser transmitters and receivers to cover multiple elevation angles at the same time. This type of laser radar transmitter requires the use of multiple sets of laser transceivers and requires precise optical calibration (usually done manually), which is expensive and the mechanical rotating device is prone to failure. Summary of the invention

[0004] Based on this, it is necessary to provide a laser emitting mechanism and a phased array laser radar. The laser emitting mechanism has low cost, high measurement reliability, and low failure rate; the phased array laser radar uses the aforementioned laser emitting mechanism to emit detection laser, thereby improving the overall measurement reliability.

[0005] The technical solution is as follows:

[0006] On the one hand, a laser emitting mechanism is provided, including a laser, the laser is used to generate a laser light source, and the laser is provided with at least one; and a phased array unit, the phased array unit is provided with at least one phased array unit, the phased array unit is optically connected to the corresponding laser, and the phased array unit is used to receive the laser light source generated by the laser and emit the laser light source as a detection laser toward the object to be measured.

[0007] The technical solution is further described below:

[0008] In one embodiment, there is one laser, there are multiple phased array units, and the laser emitting mechanism also includes a beam splitter, which is arranged between the laser and the phased array unit. The beam splitter is used to split the laser emitted by the laser and make the split laser correspond to the phased array unit.

[0009] In one embodiment, the phased array units are arranged at intervals and in rows, and the phased array units are one-dimensional phased arrays.

[0010] In one of the embodiments, the laser is provided with one, the laser is a tunable laser, and the phased array unit is provided with one, the phased array unit is a one-dimensional phased array.

[0011] In one of the embodiments, the laser is provided with one, the phased array unit is provided with one, and the phased array unit is a two-dimensional phased array.

[0012] In one embodiment, a plurality of lasers are provided, and a plurality of phased array units are provided and arranged corresponding to the lasers.

[0013] In one of the embodiments, at least two phased array units are installed at different elevation angles.

[0014] In one of the embodiments, the installation elevation angles of the phased array units are the same, and the laser emitting mechanism further includes a deflection assembly, which includes a plurality of optical deflection members for deflecting the lasers emitted by the phased array units, and the optical deflection members correspond one-to-one to the phased array units.

[0015] In one embodiment, the optical deflecting element is a transmissive element or a reflective element.

[0016] On the other hand, a phased array laser radar is also provided, comprising a laser emitting mechanism as described in any of the above technical solutions; and a laser receiving mechanism, the laser receiving mechanism being used to receive the echo laser reflected by the object being measured.

[0017] The above-mentioned laser emitting mechanism adopts a combination of a laser and a phased array unit. The laser and the phased array unit are matched and set according to the quantity required, and can be used together to perform multi-dimensional scanning. No traditional mechanical rotation device is required, the cost is low, the measurement reliability is high, and the failure rate is low.

[0018] The above-mentioned phased array laser radar uses the aforementioned laser emitting mechanism to emit detection laser and cooperates with the laser receiving mechanism to measure distance. Therefore, it is not only low-cost but also has high measurement reliability and low failure rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is an overall structural diagram of a first embodiment of a laser emitting mechanism;

[0020] Figure 2 for Figure 1 Schematic diagram of lateral adjustment and longitudinal adjustment of the embodiment;

[0021] Figure 3 is an overall structural diagram of a second embodiment of a laser emitting mechanism;

[0022] Figure 4 is an overall structural diagram of a third embodiment of a laser emitting mechanism;

[0023] Figure 5 This is a diagram of a first embodiment of a longitudinal arrangement of a single one-dimensional phased array;

[0024] Figure 6A second embodiment diagram of the longitudinal arrangement of a single one-dimensional phased array;

[0025] Figure 7 A third embodiment diagram of the longitudinal arrangement of a single one-dimensional phased array;

[0026] Figure 8 A diagram showing a first embodiment of a longitudinal arrangement of multiple one-dimensional phased arrays;

[0027] Fig. 9 A diagram showing a second embodiment of a longitudinal arrangement of multiple one-dimensional phased arrays;

[0028] Fig.10 A third embodiment diagram of the longitudinal arrangement of multiple one-dimensional phased arrays;

[0029] Fig.11 Schematic diagram of the overall structural framework of the phased array laser radar in the embodiment.

[0030] Notes on the attached drawings:

[0031] 100. Laser, 200. Phased array unit, 210. One-dimensional phased array, 220. Two-dimensional phased array, 230. Optical deflector, 231. First deflector, 232. Second deflector, 300. Receiving end optical unit, 400. Laser receiver, 500. Object to be measured. DETAILED DESCRIPTION

[0032] The embodiments of the present invention are described in detail below with reference to the accompanying drawings:

[0033] It should be noted that when an element is referred to herein as being "fixed" to another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be a central element at the same time. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0035] like Figures 1 to 10The embodiment shown provides a laser emitting mechanism, including a laser 100, the laser 100 is used to generate a laser light source, and the laser 100 is provided with at least one; and a phased array unit 200, the phased array unit 200 is provided with at least one, the phased array unit 200 is optically connected to the corresponding laser 100, and the phased array unit 200 is used to receive the laser light source generated by the laser 100 and emit the laser light source as a detection laser toward the object 500 to be measured.

[0036] The emitting end of the laser emitting mechanism uses a laser 100 in combination with a phased array unit 200. The laser 100 and the phased array unit 200 are matched and set according to the required quantity, and can be used together to perform multi-dimensional scanning without the need for traditional mechanical rotation devices, with low cost and high measurement reliability.

[0037] Traditional laser radar uses a mechanical rotating device to perform 360° circular scanning, and integrates multiple sets of laser transmitters and receivers to simultaneously cover multiple pitch angles, thereby achieving multi-directional scanning. However, this type of laser radar is expensive, the rotation accuracy is difficult to control, it is prone to failure, and the laser reception efficiency is relatively poor.

[0038] The laser emitting mechanism provided in this embodiment includes a laser 100 and a phased array unit 200. The laser 100 is used to generate a laser light source, and the phased array unit 200 is used to receive the laser light source emitted by the laser 100 and emit the laser light source as a detection laser toward the object 500 to be measured.

[0039] The phased array unit 200 refers to an optical phased array, or Optical Phased Array, or OPA for short. The phased array lidar provided in this embodiment uses a phased array unit 200 (ie, OPA) to replace the scanning method of a mechanical rotating device. The optical phased array is composed of many identical antennas forming a matrix, and the radiation waves of all antennas form a beam of radar waves through interference in the far field. The electronic system controls the phase of each antenna in real time, thereby controlling the direction of the radar wave in the far field. By changing the phase of certain antennas, the electronic system can change the direction of the radar wave (ie, the detection laser), thereby achieving dynamic scanning. Such electronic scanning does not require a mechanical rotating device, has a fast scanning rate, and even if a small number of antennas fail, it will not affect the actual use of the optical phased array.

[0040] The use of optical phased arrays only requires a single element to complete a scan within a spatial stereoscopic angle; at the same time, the use of fully automatic, large-scale photonic integrated circuit manufacturing and packaging processes does not require the complex and time-consuming installation and calibration process of mechanical rotating device laser radars, thereby reducing costs. At the same time, phased array laser radars do not have high-speed rotating mechanical parts, and the measurement reliability can be further improved compared to traditional laser radars.

[0041] The phased array unit 200 is a unidirectional optical device. When the phased array unit 200 is used to form a laser radar, it is necessary to collect and detect the radar echo signal (i.e., echo laser) reflected by the detection laser emitted by the phased array unit 200 in various directions in space.

[0042] In addition, at least one laser 100 is provided and at least one phased array unit 200 is provided, so that a specific configuration is performed according to the specific type of laser 100 or the type of phased array unit 200, and a laser emitting end is formed, thereby meeting the requirements of laser radar detection of different types and requirements and reducing costs.

[0043] It should be noted that:

[0044] The phased array unit 200 is optically connected to the laser 100 . The optical connection here refers to a connection setting that ensures light energy has low attenuation transmission between optical waveguides or between optical waveguides and optical passive devices or between optical waveguides and optical source devices.

[0045] like Figure 1 In the embodiment shown, one laser 100 is provided, and a plurality of phased array units 200 are provided. The laser emitting mechanism further includes a beam splitter, which is provided between the laser 100 and the phased array unit 200. The beam splitter is used to split the laser emitted by the laser 100 and make the split laser correspond to the phased array unit 200.

[0046] like Figure 1 As shown, the laser 100 is provided with one, and the phased array units 200 are provided with multiple ones. The phased array units 200 and the laser 100 are optically connected, and this optical connection can be a connection based on optical fiber or a connection based on free-space optical elements. The laser light emitted by the laser 100 is split by a beam splitter, and the split laser light is coupled into the corresponding phased array unit 200, and the phased array unit 200 emits the split laser light (i.e., the detection laser) toward the object 500 to be measured.

[0047] Of course, the beam splitter here can also be implemented in the form of branching, which will not be repeated here.

[0048] like Figure 1 and Figure 2 In the illustrated embodiment, the phased array units 200 are arranged at intervals and in rows, and the phased array units 200 are a one-dimensional phased array 210 .

[0049] The phased array units 200 are arranged in a row. Since the phased array units 200 are one-dimensional phased arrays 210, the one-dimensional phased array 210 scans in one-dimensional direction, and the phased array units 200 in a row thereby realize another-dimensional scanning in the arrangement direction, thereby realizing multi-directional scanning.

[0050] like Figure 1 and Figure 2 As shown, the beam deflection direction of the one-dimensional phased array 210 achieved by phase modulation is defined as horizontal, and the rows are arranged as follows Figure 1 The longitudinal arrangement direction is longitudinal; therefore, transverse and longitudinal scanning can be achieved through the longitudinal arrangement of multiple one-dimensional phased arrays 210 and phase adjustment.

[0051] like Figure 3 In the illustrated embodiment, the laser 100 is provided with one, the laser 100 is a tunable laser 100 , and the phased array unit 200 is provided with one, the phased array unit 200 is a one-dimensional phased array 210 .

[0052] The tunable laser 100 refers to a laser 100 with tunable wavelength to generate a light source. When the output laser wavelength changes, the light beam passes through the phased array unit 200 and is emitted to different longitudinal angles, thereby achieving longitudinal light beam deflection and longitudinal scanning.

[0053] In addition, when the phased array unit 200 is provided with one one-dimensional phased array 210, the longitudinal scanning modes include the following:

[0054] like Figure 5 In the illustrated embodiment, the laser 100 is a tunable laser 100, and the tunable laser 100 cooperates with the transmitting antenna of the phased array unit 200 as a dispersion device to realize longitudinal scanning of wavelength modulation;

[0055] like Figure 6 In the embodiment shown, the laser 100 is also a tunable laser 100, and an independent first deflection element 231 (such as a grating or a prism) is used outside the one-dimensional phased array 210 as a dispersion element to achieve longitudinal scanning of wavelength modulation;

[0056] like Figure 7 In the illustrated embodiment, a non-dispersive second deflection element 232 (eg, a micro-electromechanical system) is used to achieve longitudinal scanning.

[0057] Figure 5 and Figure 6In the modulation method of the wavelength tunable laser 100, the temperature modulation or current modulation of the semiconductor laser 100, the MEMS resonant cavity modulation of the solid laser 100 or the external cavity semiconductor laser 100 can be adopted. Of course, other existing laser wavelength tuning methods can also be adopted. When a single one-dimensional phased array 210 is used for two-dimensional angle (i.e., horizontal and vertical) spatial scanning, depending on the relative speed of wavelength modulation and phase modulation, the longitudinal scanning can be used as the fast axis when the wavelength modulation is faster; the longitudinal scanning is used as the slow axis when the phase modulation is faster; in addition, if the speeds of the two are basically the same, random point scanning in the two-dimensional angle space can be realized relatively easily.

[0058] like Figure 4 In the illustrated embodiment, the laser 100 is provided with one, the phased array unit 200 is provided with one, and the phased array unit 200 is a two-dimensional phased array 220 .

[0059] The two-dimensional phased array 220 refers to a phased array unit 200 that can achieve lateral scanning and longitudinal scanning without the aid of other devices. It directly cooperates with the laser 100. The laser source emitted by the laser 100 will be directly coupled into the two-dimensional phased array 220 and the detection laser will be emitted toward the object 500 to be measured.

[0060] It should be noted that the phased array unit 200 can achieve non-sequential and non-continuous beam scanning in time and space by diffracting the synthesized scanning beam. The one-dimensional phased array 210 (1D-OPA) is a phased array device with a set of linear transmitting antennas, which has the ability to modulate the beam emission angle along the linear antenna direction; the two-dimensional phased array 220 (2D-OPA) is a phased array device with multiple transmitting antennas distributed on a two-dimensional plane, which has the ability to modulate the beam emission angle in any direction.

[0061] Of course, as needed, it can also be understood that: the one-dimensional phased array 210 refers to a plurality of phased array units 200 arranged at intervals along one direction (such as horizontal arrangement or vertical arrangement), and the two-dimensional phased array 220 refers to a plurality of phased array units 200 arranged on a plane according to preset requirements.

[0062] At this time, the phased array unit 200 is a two-dimensional phased array 220, which should be understood as: there are multiple phased array units 200, and they are arranged and set on a plane according to preset requirements. The phased array unit 200 is used here as a two-dimensional phased array 220 only for the purpose of explanation and writing, and will not be repeated.

[0063] In one embodiment, a plurality of lasers 100 are provided, and a plurality of phased array units 200 are provided and are arranged corresponding to the lasers 100 .

[0064] There are multiple lasers 100 , and the phased array units 200 are arranged corresponding to the number of lasers 100 and optically connected to each other accordingly. The laser light sources emitted by the multiple lasers 100 are coupled into the corresponding phased array units 200 .

[0065] like Figure 8 In the embodiment shown, the installation elevation angles of at least two phased array units 200 are different. By adjusting the installation elevation angles of the phased array units 200, the light beam emitted by each phased array unit 200 corresponds to a pitch angle, thereby achieving the purpose of longitudinal scanning.

[0066] It should be noted that the installation elevation angle of the phased array unit 200 refers to the angle between the straight line where the default emission light beam of the phased array unit 200 is located and the plane where the phased array unit 200 itself is located.

[0067] like Figure 8 As shown, the transmitting antenna of each phased array unit 200 (such as the one-dimensional phased array 210) is longitudinally oriented relative to its normal ( Figure 8 There is a default angle (dashed line in FIG. 1 ), which is determined by the phased array unit 200. The installation elevation angles of all phased array units 200 are adjusted mechanically. In this elevation adjustment method, each phased array unit 200 is manufactured on a separate optoelectronic chip.

[0068] like Fig. 9 In the illustrated embodiment, the installation elevation angles of the phased array units 200 are the same, a portion of the phased array units 200 are arranged toward a first direction, and another portion of the phased array units 200 are arranged toward a second direction.

[0069] like Fig. 9 In the embodiment shown, the default angle is changed by changing the internal settings of the phased array unit 200 (such as the one-dimensional phased array 210). This change can usually only be made to the normal ( Fig. 9 The elevation angle can be adjusted on one side of the phased array 210 by rotating the phased array unit 200 in the vertical direction, and on the other side of the entire longitudinal direction, the phased array unit 200 needs to be inverted to achieve this, that is, a part of the phased array unit 200 is arranged normally, and the other part is arranged inverted (such as arranged by rotating 180° relative to each other). This arrangement allows multiple one-dimensional phased arrays 210 to be integrated and manufactured on the same optoelectronic chip. Figure 8 The embodiment shown has a more compact structure and lower cost.

[0070] like Fig.10 In the embodiment shown, the installation elevation angles of the phased array units 200 are the same, and the laser emitting mechanism further includes a deflection assembly, which includes a plurality of optical deflection members 230 for deflecting the laser emitted by the phased array unit 200, and the optical deflection members 230 are arranged in a one-to-one correspondence with the phased array units 200.

[0071] The installation elevation angles of multiple phased array units 200 (such as the one-dimensional phased array 210) are the same, that is, the initial installation elevation angles of the phased array units 200 are the same. When the phased array unit 200 emits a detection laser toward the object 500 to be measured, the emitted laser beam is deflected by the optical deflection element 230, so that the beam is deflected to different elevation angles, thereby achieving the purpose of scanning in different directions (longitudinal).

[0072] Furthermore, the optical deflection element 230 can be a transmission element or a reflection element. The deflection processing method using the optical deflection element 230 has high reliability and allows multiple one-dimensional phased arrays 210 to be integrated on the same optoelectronic chip, which can meet the small-size installation requirements.

[0073] Figures 8 to 10 The given embodiment is a longitudinal arrangement of multiple one-dimensional phased arrays 210. Of course, those skilled in the art can also make specific settings as needed, including but not limited to the present embodiment, which will not be described in detail here.

[0074] like Fig.11 The illustrated embodiment provides a phased array laser radar, comprising a laser emitting mechanism as described in any of the above embodiments; and a laser receiving mechanism, the laser receiving mechanism being used to receive the echo laser reflected by the object 500 to be measured.

[0075] Since the aforementioned laser emitting mechanism is used to emit the detection laser and is used in conjunction with the laser receiving mechanism to measure the distance, it is not only low in cost but also has high measurement reliability and low failure rate.

[0076] Furthermore, the laser receiving mechanism includes a receiving end optical unit 300 and a laser receiver 400 arranged corresponding to the receiving end optical unit 300 , the receiving end optical unit 300 is used to receive the echo laser reflected by the measured object 500 , and the laser receiver 400 is used to couple the echo laser.

[0077] The laser receiving mechanism in this embodiment includes a receiving end optical unit 300 and a laser receiver 400. The receiving end optical unit 300 is independent of the laser emitting mechanism, can work more stably, improve detection accuracy, and avoid mutual interference. The laser receiver 400 can couple the echo laser and perform photoelectric signal conversion, so as to obtain the measurement result based on the preset requirements.

[0078] Of course, the receiving end optical unit 300 and the laser receiver 400 (any detectors that can meet the requirements can be selected) can be specifically selected according to needs.

[0079] It should be noted that:

[0080] The receiving end optical unit 300 in this embodiment can be a lens, or a lens group, specifically, a wide-angle receiving lens. A wide-angle receiving lens refers to a lens with a large viewing angle and capable of covering a wide range of echo laser reception. Those skilled in the art can also select different lens groups as needed to meet actual needs, which will not be described in detail here;

[0081] The laser receiver 400 may be a photodetector, which is used to couple the echo laser of the wide-angle receiving lens and convert the optical signal into an electrical signal. Of course, those skilled in the art may make specific selections according to their needs. The photodetector is only for the convenience of explanation. If necessary, the photodetector here may also be other non-photoelectric conversion detector structures to meet actual needs, which will not be described here.

[0082] The corresponding setting of the laser receiver 400 and the receiving end optical unit 300 refers to the corresponding setting that the laser receiver 400 can connect to the echo laser received by the receiving end optical unit 300 and can couple and perform photoelectric conversion on it. Those skilled in the art can make specific settings and will not be repeated here.

[0083] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0084] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A laser emitting mechanism, characterized in that: include: A laser, the laser being used to generate a laser light source, and a plurality of the lasers are provided; and a phased array unit, wherein a plurality of the phased array units are provided and are arranged corresponding to the lasers; the phased array unit is optically connected to the corresponding lasers, and the phased array unit is used to receive the laser light source generated by the laser and emit the laser light source as a detection laser toward the object to be measured; The installation elevation angles of at least two of the phased array units are different, and by adjusting the installation elevation angles of the phased array units, the light beam emitted by each phased array unit corresponds to a pitch angle.

2. A laser emitting mechanism, characterized in that: include: A laser, the laser being used to generate a laser light source, and a plurality of the lasers are provided; and a phased array unit, wherein a plurality of the phased array units are provided and are arranged corresponding to the lasers; the phased array unit is optically connected to the corresponding lasers, and the phased array unit is used to receive the laser light source generated by the laser and emit the laser light source as a detection laser toward the object to be measured; The installation elevation angles of the phased array units are the same, a portion of the phased array units are arranged normally, and another portion of the phased array units are arranged inverted, and the laser emitting mechanism also includes a deflection assembly, which includes a plurality of optical deflection members for deflecting the lasers emitted by the phased array units, and the optical deflection members correspond one-to-one to the phased array units.

3. The laser emitting mechanism according to claim 2, characterized in that: The optical deflection element is a transmission element or a reflection element.

4. A phased array laser radar, characterized in that: include: The laser emitting mechanism according to any one of claims 1 to 3; and The laser receiving mechanism is used to receive the echo laser reflected by the object to be measured.

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