MEMS galvanometer laser radar system and electronic equipment

Abstract

The invention provides an MEMS galvanometer laser radar system. The MEMS galvanometer laser radar system comprises a transmitting module, a receiving module, a processing module and a control module. The transmitting module comprises an MEMS galvanometer module, a light source module and a deflection angle amplification module. And the MEMS galvanometer module deflects different reflection angles of the light beams in sequence in a time-sharing manner. The light source module emits a light beam corresponding to the reflection angle of the scanning path. And the deflection angle amplification module amplifies the deflection angle of the reflected and deflected light beam in the corresponding deflection direction by a preset multiple. The receiving module comprises a photoelectric sensor and a receiving optical device, and the receiving optical device transmits optical signals from different directions of the view field range to corresponding photosensitive pixels on the photoelectric sensor. The processing module is used for obtaining three-dimensional information according to the light sensing signals output by the light sensing pixels. The control module controls the corresponding photosensitive pixels to work in sequence in a time-sharing mode according to the scanning direction of the light beams. The invention further provides electronic equipment comprising the MEMS galvanometer laser radar system.

Description

Technical Field

[0001] The present application relates to the field of photoelectric detection, and in particular to a MEMS (MicroElectromechanical System) galvanometer laser radar system and electronic equipment that realizes light beam deflection through a MEMS galvanometer. Background Art

[0002] LiDAR's ranging function is typically based on the Time of Flight (ToF) measurement principle. This involves emitting laser pulses into the measurement scene and measuring the time it takes for the laser pulses to travel back and forth between the LiDAR and the target object to calculate three-dimensional information such as the distance to the target object. Due to its advantages of long sensing range, high accuracy, and low energy consumption, ToF measurement is widely used in consumer electronics, intelligent driving, unmanned aerial vehicles, AR / VR, and other fields.

[0003] A single beam of light emitted by a detection device that uses the ToF measurement principle for ranging can only cover a limited field of view. A larger field of view must be achieved by continuously changing the beam's direction and scanning it. Currently, a common method for changing the beam's direction is to mechanically rotate the detection device's transmitting and receiving modules. However, this method often requires multiple discrete components assembled into a mechanical rotating structure, which complicates debugging and assembling the transmitting / receiving optical paths. The mechanical rotating structure is also prone to damage and misalignment. Furthermore, its large size can affect the appearance of the terminal device using it. Summary of the Invention

[0004] In view of this, the present application provides a MEMS galvanometer laser radar system and related electronic equipment that can improve the problems of the existing technology.

[0005] In a first aspect, the present application provides a MEMS galvanometer laser radar system configured to perform three-dimensional information sensing of a field of view along a preset scanning path, comprising:

[0006] Transmitter module, including:

[0007] The MEMS galvanometer module is configured to sequentially deflect different reflection angles of the light beam at different time periods;

[0008] A light source module is configured to emit a light beam corresponding to a reflection angle where the scanning path is located; and

[0009] A deflection angle magnification module is configured to magnify the deflection angle of the light beam reflected by the MEMS galvanometer module in the corresponding deflection direction by a preset multiple;

[0010] The receiving module is configured to sense the optical signal from the field of view, including:

[0011] A photosensor, comprising a plurality of light-sensitive pixels, configured to respond to light signals and output corresponding light-sensing signals;

[0012] and

[0013] A receiving optical device is configured to transmit light signals from different directions within the field of view to corresponding photosensitive pixels respectively;

[0014] a processing module configured to process the light sensing signal to obtain three-dimensional information; and

[0015] The control module is configured to control the MEMS galvanometer module to deflect the reflection angle of the light beam in sequence, control the light source module to emit the light beam at the reflection angle corresponding to the deflection path, and control the corresponding photosensitive pixels to work in sequence and time-sharing according to the scanning direction of the light beam.

[0016] In a second aspect, the present application provides an electronic device comprising an application module and the MEMS galvanometer laser radar system as described above. The application module is configured to implement corresponding functions according to the detection results of the MEMS galvanometer laser radar system.

[0017] Beneficial effects of this application:

[0018] Compared with the deflection of the light beam achieved through mechanical rotation solutions and hybrid solid-state solutions, the present application uses a MEMS galvanometer module to achieve two-dimensional deflection scanning of the light beam within a preset deflection angle range. It does not need to rely on fragile and bulky rotating parts, and has the beneficial effects of better reliability and compact size. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings.

[0020] Figure 1 A schematic diagram of the functional modules of an electronic device provided in one embodiment of the present application;

[0021] Figure 2 for Figure 1 A schematic diagram of the functional modules of an embodiment of the MEMS galvanometer laser radar system described in the specification;

[0022] Figure 3 for Figure 2 Schematic diagram of the optical path of the transmitting module of the MEMS galvanometer laser radar system;

[0023] Figure 4 A schematic diagram of the beam scanning path of a MEMS galvanometer laser radar system provided in one embodiment of the present application;

[0024] Figure 5A schematic diagram of the beam scanning path of a MEMS galvanometer laser radar system provided in one embodiment of the present application;

[0025] Figure 6 A schematic diagram of the beam scanning path of a MEMS galvanometer laser radar system provided in one embodiment of the present application;

[0026] Figure 7 A schematic diagram of the beam scanning path of a MEMS galvanometer laser radar system provided in one embodiment of the present application;

[0027] Figure 8 A schematic diagram showing how the frequency of an emission light beam of a MEMS galvanometer laser radar system varies with the scanning path provided in one embodiment of the present application;

[0028] Figure 9 A schematic diagram showing how the power of an emission beam of a MEMS galvanometer laser radar system varies with the scanning path provided in one embodiment of the present application;

[0029] Figure 10 for Figure 3 A schematic diagram of an optical path of an embodiment of a deflection angle amplification module of the emission module;

[0030] Figure 11 for Figure 3 A schematic diagram of an optical path of an embodiment of a deflection angle amplification module of the emission module;

[0031] Figure 12 A schematic structural diagram of a MEMS galvanometer lidar system provided in one embodiment of the present application as an automotive lidar. DETAILED DESCRIPTION

[0032] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and are not to be construed as limitations on the present application. In the description of the present application, it should be understood that the terms "first" and "second" are only used for description and are not to be construed as indicating or implying relative importance or implicitly indicating the number or arrangement order of the indicated technical features. Thus, the technical features defined as "first" and "second" may explicitly or implicitly include one or more of the technical features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0033] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integrated connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0034] The disclosure below provides many different embodiments or examples for implementing different structures of the present application. In order to simplify the disclosure of the present application, only the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may reuse reference numbers and / or reference letters in different examples. This repetition is for the purpose of simplifying and clearly stating the present application and does not itself indicate a specific relationship between the various embodiments and / or settings discussed. In addition, the various specific processes and materials provided in the description below are merely examples for implementing the technical solutions of the present application, but those of ordinary skill in the art should appreciate that the technical solutions of the present application may also be implemented by other processes and / or other materials not described below.

[0035] Further, described feature, structure can be combined in one or more embodiments in any suitable manner.In the description below, many specific details are provided so that the embodiments of the present application can be fully understood. However, it will be appreciated by those skilled in the art that even without one or more of the specific details, or by adopting other structures, components etc., the technical scheme of the present application can also be put into practice. In other cases, known structures or operations are not shown or described in detail to avoid blurring the key points of the present application.

[0036] An embodiment of the present application provides a MEMS galvanometer laser radar system configured to sense three-dimensional information within a field of view along a preset scanning path, including:

[0037] Transmitter module, including:

[0038] The MEMS galvanometer module is configured to sequentially deflect different reflection angles of the light beam at different time periods;

[0039] A light source module is configured to emit a light beam corresponding to a reflection angle where the scanning path is located; and

[0040] A deflection angle magnification module is configured to magnify the deflection angle of the light beam reflected by the MEMS galvanometer module in the corresponding deflection direction by a preset multiple;

[0041] The receiving module is configured to sense the optical signal from the field of view, including:

[0042] A photosensor, comprising a plurality of light-sensitive pixels, configured to respond to light signals and output corresponding light-sensing signals;

[0043] and

[0044] A receiving optical device is configured to transmit light signals from different directions within the field of view to corresponding photosensitive pixels respectively;

[0045] a processing module configured to process the light sensing signal to obtain three-dimensional information; and

[0046] The control module is configured to control the MEMS galvanometer module to deflect the reflection angle of the light beam in sequence, control the light source module to emit the light beam at the reflection angle corresponding to the deflection path, and control the corresponding photosensitive pixels to work in sequence and in a time-sharing manner according to the scanning direction of the light beam. The three-dimensional information is, for example: proximity information of objects within the field of view, depth information of the object surface, coordinate information of the object in the field of view, and corresponding distance information, etc. The three-dimensional information can be used, for example, in 3D modeling, identity recognition, automatic driving, machine vision, monitoring, drone control, augmented reality (AR) / virtual reality (VR), simultaneous localization and mapping (SLAM), object proximity judgment and other fields, and this application does not limit this.

[0047] In some embodiments, the photosensitive pixel includes at least one photoelectric conversion device.

[0048] In some embodiments, the photoelectric conversion device may be a single photon avalanche diode, an avalanche photodiode, or a silicon photomultiplier tube, or any one or more combinations thereof.

[0049] In some embodiments, the MEMS galvanometer module is a two-dimensional MEMS galvanometer module, configured to change a reflection angle of a light beam along a first direction and a second direction, wherein the first direction and the second direction are perpendicular to each other.

[0050] In some embodiments, the first direction is a horizontal direction, and the second direction is a vertical direction; or, the first direction is a vertical direction, and the second direction is a horizontal direction.

[0051] In some embodiments, the deflection trajectory of the reflection angle is defined as the reflection path of the MEMS galvanometer module for the light beam, and the reflection path includes multiple first divisions and multiple second divisions connecting different first divisions, the first divisions are line segments parallel to the first direction, and the multiple first divisions are arranged parallel to each other and spaced apart in sequence along the second direction.

[0052] In some embodiments, the second division is a line segment parallel to the second direction, and the second division connects the ends of two adjacent first divisions on the same side, and the deflection directions of the reflection angles of the light beam on the two adjacent first divisions are opposite; or, the second division is a line segment inclined relative to the first direction, and the second division connects the ends of two adjacent first divisions on different sides, and the deflection directions of the reflection angles of the light beam on the two adjacent first divisions are the same.

[0053] In some embodiments, a frame detection of the entire field of view includes multiple scanning periods and an intermittent period connecting two adjacent scanning periods; wherein the control module is configured to control the MEMS galvanometer module and the light source module to perform scanning sensing along one of the first divisions in one scanning period, control the MEMS galvanometer module to adjust the reflection angle of the light beam to the reflection angle corresponding to the light beam when starting to scan and sense the next first division during the intermittent period, and control the light source module to stop emitting the light beam during the intermittent period.

[0054] In some embodiments, the control module is configured to control the processing module to process the light sensing signal data obtained after scanning and sensing the previous first sub-section during the intermittent period.

[0055] In some embodiments, the first section includes a middle section and a first section and a second section located on opposite sides of the middle section, and the MEMS galvanometer module is configured to deflect the light beam reflection angle at a higher speed in the middle section than in the first section and the second section.

[0056] In some embodiments, the first section includes a middle section and a first section and a second section located on opposite sides of the middle section, and the control module is configured to control the light source module to emit a light beam at a frequency higher than that when scanning the first section and the second section when scanning the middle section.

[0057] In some embodiments, the first section includes a middle section and a first section and a second section located on opposite sides of the middle section, and the control module is configured to control the light source module to emit a light beam with a power higher than that of the light beam when scanning the middle section.

[0058] In some embodiments, the first section includes a middle section and a first section and a second section located on opposite sides of the middle section, and the control module is configured to control the light source module to emit a light beam less times when scanning the middle section than when scanning the first section and the second section.

[0059] In some embodiments, the deflection angle magnification module includes a lens group having a plurality of lenses; or, the deflection angle magnification module includes a super lens.

[0060] An embodiment of the present application also provides an electronic device, which includes the MEMS galvanometer laser radar system. The electronic device implements corresponding functions based on the three-dimensional information obtained by the MEMS galvanometer laser radar system. The electronic device is, for example, a mobile phone, a car, a robot, an access control / monitoring system, a smart door lock, an unmanned mobile vehicle, an aircraft, etc. Taking a smart driving vehicle as an example, a MEMS galvanometer laser radar system is set in the smart driving vehicle to scan the surrounding environment by rapidly and repeatedly emitting laser pulses as a light beam to obtain point cloud data of the shape, position and movement of objects within the field of view.

[0061] Hereinafter, an embodiment of a MEMS galvanometer laser radar system applied to an electronic device will be described in detail with reference to the accompanying drawings.

[0062] Figure 1 This is a schematic diagram of the functional modules of the MEMS galvanometer lidar system provided in an embodiment of the present application applied to electronic equipment. Figure 2 This is a schematic diagram of the functional modules of the MEMS galvanometer lidar system provided in an embodiment of the present application.

[0063] Reference Figure 1 and Figure 2 The electronic device 1 includes a MEMS galvanometer laser radar system 10. The MEMS galvanometer laser radar system 10 is configured to perform three-dimensional information sensing in a field of view along a preset scanning path. The field of view can be defined as the three-dimensional spatial range in which the MEMS galvanometer laser radar system 10 can effectively perform three-dimensional information detection, which can also be referred to as the field of view angle or field of view range of the MEMS galvanometer laser radar system 10.

[0064] The electronic device 1 may include an application module 20, which is configured to perform preset operations or implement corresponding functions based on the detection results of the MEMS galvanometer laser radar system 10, such as but not limited to: determining whether an object 2 appears within a preset field of view in front of the electronic device 1 based on the proximity information of the object 2; or controlling the movement of the electronic device 1 to perform obstacle avoidance or navigation, 3D modeling, machine vision, etc. based on the distance information and orientation information of the object 2 within the field of view; or realizing identity recognition based on the depth information of the surface of the object 2. That is, the application module 20 may be a collection of hardware required to perform the above operations and implement the above functions, and software required to control and coordinate the operation of the hardware.

[0065] The electronic device 1 may further include a storage medium 30, which may support the storage requirements of the electronic device 1 and / or the MEMS galvanometer laser radar system 10 during operation. Figure 1 As shown, in some embodiments, the storage medium 30 may be disposed inside the electronic device 1. Figure 2 As shown, in some embodiments, the storage medium 30 may also be disposed inside the MEMS galvanometer laser radar system 10 .

[0066] The electronic device 1 may further include a processor 40, which can support the data processing requirements of the electronic device 1 and / or the MEMS galvanometer laser radar system 10 during operation. Figure 1 As shown, in some embodiments, the processor 40 may be disposed inside the electronic device 1. Figure 2 As shown, in some embodiments, the processor 40 may also be disposed inside the MEMS galvanometer lidar system 10 .

[0067] Optionally, in some embodiments, the MEMS galvanometer laser radar system 10 can, for example, perform three-dimensional information sensing based on the direct time of flight (dToF) principle, by emitting a light beam into the field of view and receiving a light beam reflected by an object 2 within the field of view. The time difference between the emission moment and the reception moment of the reflected light beam is called the flight time t of the light beam. The three-dimensional information of the object 2 can be obtained by calculating half of the distance traveled by the light beam within the flight time t. Where c is the speed of light.

[0068] In some other embodiments, the MEMS galvanometer lidar system 10 can also perform three-dimensional information sensing based on the indirect Time of Flight (iToF) measurement principle, and obtain three-dimensional information of the object 2 by comparing the phase difference when the light beam is emitted and when it is reflected back and received.

[0069] In some other embodiments, the MEMS galvanometer lidar system 10 can also perform three-dimensional information sensing based on the frequency modulated continuous wave (FMCW) measurement principle, by interfering the return light and the transmitted light, and using mixing detection technology to measure the frequency difference between the sending and receiving, and then converting the frequency difference into the distance of the target object.

[0070] In the following embodiments of this application, the dToF measurement principle of the MEMS galvanometer laser radar system 10 is mainly described as an example.

[0071] In some embodiments, as Figure 2 As shown, the MEMS galvanometer laser radar system 10 includes a transmitting module 12, a receiving module 14 and a processing module 15. The transmitting module 12 is configured to transmit a light beam to the field of view, and deflect the irradiation direction of the light beam in time-sharing according to a preset scanning path to achieve scanning of the entire field of view, wherein part of the light beam will be reflected by the object 2 and returned, and the reflected light beam echo carries the three-dimensional information of the object 2, wherein part of the light beam echo can be sensed by the receiving module 14 to obtain the three-dimensional information of the object 2. The receiving module 14 is configured to sense the light signal from the field of view and output the corresponding light sensing signal. By analyzing the light sensing signal, the three-dimensional information of the object 2 within the field of view can be detected. It can be understood that the light signal sensed by the receiving module 14 may include the light beam echo reflected by the object 2 within the field of view, and may also include the ambient light within the field of view. The processing module 15 is configured to analyze and process the light sensing signal to obtain the time when the light beam echo is sensed by the receiving module 14. For example, the light sensing signal is processed and analyzed based on the time-correlated single photon counting (TCSPC) technology to obtain the time when the light beam echo is sensed by constructing a photon count histogram. Furthermore, the processing module 15 is configured to obtain three-dimensional information about the field of view based on the time difference between the emission time of the light beam and the time when the light beam is reflected and sensed.

[0072] The processing module 15 can be provided on the MEMS galvanometer laser radar system 10, for example, in the photoelectric sensor 140 of the receiving module 14. It should be understood that in some other embodiments, all or part of the functional units of the processing module 15 can also be provided on the electronic device 1.

[0073] In some embodiments, the light beam can be, for example, a plurality of laser pulses emitted sequentially. The emission module 12 is configured to emit the laser pulses as a light beam according to a preset time sequence. Specifically, the emission module 12 time-shares the field of view partitions 13 located at different orientations within the field of view along a preset scanning path, and emits a plurality of light beam pulses to the scanned field of view partitions 13 according to a corresponding preset time sequence for three-dimensional information detection. After completing the emission of a plurality of light beam pulses to a field of view partition 13 and analyzing the time distribution of the light signal sensed by the receiving module 14, the three-dimensional information of the field of view partition 13 can be obtained. This process can be regarded as a partition detection period. After scanning the plurality of field of view partitions 13 one by one in sequence, it is regarded as completing a frame detection of the entire field of view range. The three-dimensional information of all the field of view partitions 13 in the entire field of view range can be obtained, which can be used to construct a point cloud of the entire field of view range. That is, a detection frame of the field of view range includes a plurality of partition detection periods corresponding to the scanning of all the field of view partitions 13 in the field of view range.

[0074] Optionally, the light beam is, for example, visible light, infrared light or near-infrared light, with a wavelength range of, for example, 390 nanometers (nm)-780nm, 700nm-1400nm, 800nm-1000nm, 900nm-1600nm, etc.

[0075] It should be understood that the transmitting module 12 and the receiving module 14 are arranged side by side, and an off-axis optical path is used for transmission and sensing. The light-emitting surface of the transmitting module 12 and the light-entering surface of the receiving module 14 are both facing the same side of the MEMS galvanometer laser radar system 10, and the distance between the transmitting module 12 and the receiving module 14 can be, for example, 2 millimeters (mm) to 20 mm. Since the transmitting module 12 and the receiving module 14 are relatively close to each other, although the transmission path of the light beam from the transmitting module 12 to the object 2 and the return path from the object 2 to the receiving module 14 after reflection are not completely equal, both are much larger than the distance between the transmitting module 12 and the receiving module 14, and can be regarded as approximately equal. Therefore, the distance between the object 2 and the MEMS galvanometer laser radar system 10 can be calculated based on the product of half the flight time t of the light beam reflected back by the object 2 and the speed of light c.

[0076] In some embodiments, as Figure 2As shown, the receiving module 14 may include a photoelectric sensor 140 and a receiving optical device 144. The receiving optical device 144 is arranged on the light incident side of the photoelectric sensor 140, and is configured to transmit light signals from different directions in the field of view to the corresponding photosensitive pixels 142 on the photoelectric sensor 140 for sensing. For example, the receiving optical device 144 may include a receiving lens (not shown). Optionally, the receiving lens may include a lens or multiple lenses. The photoelectric sensor 140 is configured to sense the light signal transmitted from the field of view through the receiving optical device 144 and output a corresponding light sensing signal.

[0077] In some embodiments, the receiving module 14 may also include a peripheral circuit (not shown) composed of one or more devices such as a signal amplifier and an analog-to-digital converter (ADC), and the peripheral circuit may be partially or fully integrated into the photoelectric sensor 140.

[0078] The photoelectric sensor 140 may include a single photosensitive pixel 142 or a plurality of photosensitive pixels 142. The plurality of photosensitive pixels 142 may be arranged in a two-dimensional array to form a photosensitive pixel array. The field of view of the MEMS galvanometer laser radar system 10 includes a plurality of field of view partitions 13 located in different orientations, and the plurality of photosensitive pixels 142 are configured to have a preset correspondence with the plurality of field of view partitions 13. The light signal returned from one of the field of view partitions 13 may be transmitted to the corresponding one or more photosensitive pixels 142 via the receiving optical device 144 for sensing. That is, the field of view partition 13 corresponding to the photosensitive pixel 142 may be regarded as the field of view formed by the photosensitive pixel 142 via the receiving optical device 144, and the field of view partitions 13 corresponding to the plurality of photosensitive pixels 142 are spliced together to form the field of view range of the MEMS galvanometer laser radar system. Thus, when the light beam emitted by the transmitting module 12 scans the field of view partition 13 and an object 2 exists on the field of view partition 13, the light beam echo reflected by the object 2 is transmitted through the receiving optical device 144 to the corresponding photosensitive pixel 142 for sensing. That is, the light signal returned from the field of view partition 13 includes photons of ambient light from the field of view partition 13, and when an object 2 exists in the field of view partition 13, it also includes the light beam echo projected onto the field of view partition 13 and reflected by the object 2. It should be understood that one field of view partition 13 can be configured to correspond to one photosensitive pixel 142. Alternatively, one field of view partition 13 can also be configured to correspond to multiple photosensitive pixels 142. When the field of view partition 13 is scanned, the corresponding one or more photosensitive pixels 142 are activated and start working to perform three-dimensional sensing, and the acquired light sensing signals are combined to obtain three-dimensional information of the field of view partition 13. It should be understood that the photosensitive pixels 142 corresponding to other field of view partitions 13 that are not scanned by the light beam can be controlled to stop working to reduce power consumption and reduce noise caused by ambient light.

[0079] The photosensitive pixel 142 may be a single photoelectric conversion device or include multiple photoelectric conversion devices. The photoelectric conversion device is configured to sense the received light signal and convert it into a corresponding electrical signal as the light sensing signal output. Optionally, the photoelectric conversion device may be, for example, a single photon avalanche diode (SPAD), an avalanche photon diode (APD), a silicon photomultiplier (SiPM) connected in parallel with multiple SPADs, and / or other suitable photoelectric conversion elements, or a combination of the above.

[0080] Figure 3 for Figure 2A three-dimensional schematic diagram of the optical path of an embodiment of the transmitting module 12 described in

[15] is provided. To facilitate description of the deflection scanning of the light beam emitted by the transmitting module 12, an orthogonal rectangular coordinate system is established with the direction of the central angle of the light beam along the field of view as the Y-axis, the first direction as the X-axis, and the second direction as the Z-axis. The other optical path schematics of this application are also described in this coordinate system. It should be understood that in embodiments where the first direction is horizontal and the second direction is vertical, the XOY plane represents the horizontal plane, and the YOZ plane represents the vertical plane.

[0081] like Figure 3 As shown, the transmitting module 12 is configured to deflect the light beam along a preset scanning path to perform three-dimensional information sensing on the field of view. The transmitting module 12 includes a light source module 122 , a MEMS galvanometer module 126 and a deflection angle magnification module 128 .

[0082] The light source module 122 is configured to emit a light beam according to a preset timing. The light source module 122 includes one or more light-emitting units (not shown), and the light-emitting unit is configured to emit the light beam. The light-emitting unit can be a light-emitting device in the form of a vertical cavity surface emitting laser (Vertical Cavity Surface Emitting Laser, referred to as VCSEL, which can also be translated as a vertical resonant cavity surface emitting laser), an edge emitting laser (Edge Emitting Laser, EEL), a light-emitting diode (Light Emitting Diode, LED), a laser diode (Laser Diode, LD), a fiber laser, etc. Among them, the edge-emitting laser can be a Fabry Perot (FP) laser, a distributed feedback (DFB) laser, an electro-absorption modulated laser (Electro-absorption Modulated, EML), etc., and the embodiments of the present application are not limited to this.

[0083] In some embodiments, the emission module 12 may further include a collimating module 121. The collimating module 121 is configured to collimate the light beam emitted by the light source module 122 along the optical axis to improve the collimation of the light beam emitted by the light source module 122. Optionally, the collimating module 121 may employ a collimating optical device such as a collimating lens, a super lens, or a cylindrical lens.

[0084] The MEMS galvanometer module 126 is configured to sequentially deflect the light beam at different reflection angles at different time periods, thereby achieving deflection scanning of the light beam across the field of view at different time periods. The reflection angle of the light beam can be defined as the angle at which the light beam deviates from the center of the field of view after reflection, and can also be referred to as the deflection angle of the light beam.

[0085] In some embodiments, the MEMS galvanometer module 126 is configured to deflect the reflection angle of the light beam along different two-dimensional directions. The multiple reflection angles of the light beam can be defined by the angles at which the light beam deviates from the center of the field of view along a first direction and a second direction, respectively. Optionally, the first direction and the second direction can be perpendicular to each other. For example, in some embodiments, the first direction is horizontal and the second direction is vertical; in other embodiments, the first direction is vertical and the second direction is horizontal.

[0086] In some other examples, the MEMS galvanometer module 126 is configured to deflect the reflection angle of the light beam along a one-dimensional direction. For example, the MEMS galvanometer module 126 is configured to deflect the reflection angle of the light beam only along the horizontal direction; or the MEMS galvanometer module 126 is configured to deflect the reflection angle of the light beam only along the vertical direction.

[0087] The deflection angle magnification module 128 is configured to amplify the deflection angle of the light beam reflected by the MEMS galvanometer module 126 in the corresponding deflection direction by a predetermined multiple. For example, the deflection angle magnification module 128 amplifies the deflection angle of the light beam along the first direction and / or the second direction by a corresponding multiple. Optionally, the deflection angle magnification module 128 includes a lens assembly having multiple lenses or a metalens, and the lens assembly or metalens is used to achieve the deflection angle magnification function of the light beam.

[0088] The control module 18 includes an emission control unit 182 and a deflection control unit 184. The deflection control unit 184 is configured to control the MEMS galvanometer module 126 to sequentially deflect the reflection angle of the light beam at different time periods. The deflection trajectory of the reflection angle can be defined as the reflection path of the light beam by the MEMS galvanometer module 126. It can be understood as the trajectory of the light spot changes formed at the corresponding position within the field of view when the MEMS galvanometer module 126 is in different reflection angle states, assuming that a light beam is reflected by it. It has nothing to do with whether the light beam is actually reflected.

[0089] The emission control unit 182 is configured to control the light source module 122 to emit a light beam at a preset reflection angle among the different reflection angles of the MEMS galvanometer module 126, so that the reflected light beam scans in different corresponding orientations within the field of view, forming an actual scanning path for the field of view. It should be noted that the reflection path of the light beam by the MEMS galvanometer module 126 requires the light source module 122 to cooperate with the light source module 122 to emit the light beam at the corresponding reflection angle of the reflection path in order to form an actual scanning path for the field of view. Therefore, the reflection path of the light beam by the MEMS galvanometer module 126 may include the actual scanning path of the light beam for the field of view, but the two do not need to be completely identical. The actual scanning path of the light beam is the portion of the reflection path of the light beam by the MEMS galvanometer module 126 where the light beam is actually emitted by the light source module 122. In the embodiment of the present application, the portion of the reflection path where the actual scanning path of the light beam is formed is marked with a solid line, and the portion of the reflection path that is not the actual scanning path of the light beam is marked with a dotted line.

[0090] For example, in Figure 4 In the embodiment shown, the reflection path 16 of the light beam by the MEMS galvanometer module 126 includes a plurality of first divisions 1601, wherein the first divisions 1601 are line segments parallel to the first direction, and the plurality of first divisions 1601 are arranged parallel to each other and arranged in sequence along the second direction. The area irradiated by the light beam emitted by the light source module 122 along one of the reflection angles on the reflection path 16 can be defined as the field of view partition 13 corresponding to the reflection angle. In the process of the light beam being reflected by the MEMS galvanometer module 126 and scanning along the first division 1601, the plurality of field of view partitions 13 arranged along the first division 1601 are irradiated in sequence. In this case, the first division 1601 can be used as the actual scanning path of the light beam. The reflection path 16 of the light beam by the MEMS galvanometer module 126 also includes a plurality of second divisions 1602 connecting different first divisions 1601. In the case Figure 4 In the illustrated embodiment, the second segment 1602 is a line segment parallel to the second direction, and the second segment 1602 connects the ends of two adjacent first segments 1601 on the same side. The emission control unit 182 can be configured to control the light source module 122 to continue emitting the light beam along the second segment 1602 of the light beam reflection path of the MEMS galvanometer module 126, thereby forming an actual scanning path of the light beam along the second segment 1602. Figure 4The actual scanning path is represented by a solid line in the figure. In this case, the light beam is scanned from one end to the other end along a preset direction on one of the first divisions 1601, and can be scanned to another adjacent first division 1601 through the connected second division 1602, and the scanning direction is opposite to the scanning direction on the previous first division 1601. That is, the directions of change of the reflection angles of the light beams on the two adjacent first divisions 1601 are opposite. During the scanning process of the light beam along the first division 1601, the area irradiated by each reflection angle forms a field of view partition 13. The two field of view partitions 13 scanned by the light beam at two adjacent reflection angles on the same first division 1601 can be arranged to be spliced or partially overlapped with each other, so that after all the field of view partitions 13 on a first division 1601 are superimposed, they can cover the entire field of view angle range corresponding to the first division 1601 without omission. During the deflection of the light beam along the second subsection 1602, the light beam can switch from detecting the field of view subsection 13 located at one end of one side of the current first subsection 1601 to detecting the field of view subsection 13 located at the end of the same side of another adjacent first subsection 1601. The two field of view subsections 13 scanned by the light beam at corresponding positions on two adjacent first subsections 1601 can be configured to jointly fill the gap between the two adjacent first subsections 1601. Thus, after the light beam sequentially scans the multiple first subsections 1601 arranged along the second direction, it can completely cover the entire field of view range and the field of view angle range along the second direction.

[0091] like Figure 5 As shown, in some other embodiments, the reflection path 16 of the light beam by the MEMS galvanometer module 126 includes a plurality of first divisions 1601, wherein the first divisions 1601 are line segments parallel to the first direction, and the plurality of first divisions 1601 are arranged parallel to each other and spaced apart in sequence along the second direction. The reflection path 16 of the light beam by the MEMS galvanometer module 126 also includes a plurality of second divisions 1602 connecting different first divisions 1601, wherein the second divisions 1602 are line segments inclined relative to the first direction, and respectively connect the ends of two adjacent first divisions 1601 located on different sides thereof to form a "Z"-shaped reflection path 16. The emission control unit 182 can be configured to control the light source module 122 to continue emitting the light beam on the second division 1602 of the light beam reflection path by the MEMS galvanometer module 126, so as to form an actual scanning path of the light beam on the second division 1602, Figure 5The actual scanning path is represented by a solid line in the figure. In this case, the light beam scans from one end to the other end along a preset direction on one of the first subsections 1601, and then scans to the end of the adjacent first subsection 1601 on the opposite side through the connected second subsection 1602. Then, the scanning direction on this adjacent first subsection 1601 is the same as the scanning direction on the previous first subsection 1601. That is, the light beam scans along the same scanning direction on different first subsections 1601. Similarly, the area illuminated by each reflection angle during the scanning process of the light beam along the first subsection 1601 forms a field of view partition 13. The two field of view partitions 13 scanned by the light beam at two adjacent reflection angles on the same first subsection 1601 can be arranged to be spliced or partially overlapped with each other, so that after all the field of view partitions 13 on a first subsection 1601 are superimposed, they can cover the entire field of view angle range corresponding to the first subsection 1601 without omission. During the deflection of the light beam along the second subsection 1602, the light beam can switch from detecting the field of view subsection 13 located at one end of the current first subsection 1601 to detecting the field of view subsection 13 located at the opposite end of another adjacent first subsection 1601. The field of view subsections 13 scanned by the light beam at corresponding positions on two adjacent first subsections 1601 can be configured to collectively fill the gap between the two adjacent first subsections 1601. Thus, after the light beam sequentially scans the multiple first subsections 1601 arranged along the second direction, it can completely cover the entire field of view range and the field of view angle range along the second direction.

[0092] For example, in Figure 6 In the embodiment shown, the MEMS galvanometer module 126 is configured to reflect the path 16 of the light beam. Figure 4 The embodiment shown is the same as that shown, comprising a plurality of first sub-sections 1601 parallel to the first direction and a plurality of second sub-sections 1602 parallel to the second direction, wherein the plurality of first sub-sections 1601 are arranged at intervals along the second direction, and the second sub-sections 1602 are respectively connected to the ends of two adjacent first sub-sections 1601 on the same side. Figure 4 The embodiment shown is different in that Figure 6 In the illustrated embodiment, the emission control unit 182 is configured to control the light source module 122 to emit a light beam when the MEMS galvanometer module 126 deflects and reflects at a corresponding deflection angle along the first subsection 1601 of the light beam reflection path 16, and to stop emitting the light beam when the MEMS galvanometer module 126 deflects and reflects at a corresponding deflection angle along the second subsection 1602 of the light beam reflection path 16. In this case, the emission module 12 only forms a scanning path along the first subsection 1601 of the light beam reflection path 16 with respect to the MEMS galvanometer module 126. Figure 6 The solid line represents the scanning path of this part, and no actual scanning path of the light beam is formed on the second subsection 1602 of the light beam reflection path 16 by the MEMS galvanometer 126. Figure 6The dotted line in FIG represents the partial reflection path 16. Thus, in Figure 6 In the illustrated embodiment, the actual scanning path of the light beam formed by the transmitting module 12 in the field of view is a plurality of first sub-sections 1601 in the light beam reflection path 16 of the MEMS galvanometer module 126 that are parallel to the first direction and spaced apart along the second direction.

[0093] For example, in Figure 7 In the embodiment shown, the MEMS galvanometer module 126 is configured to reflect the path 16 of the light beam. Figure 5 The embodiment shown is the same as that shown, comprising a plurality of first sub-sections 1601 parallel to the first direction and a plurality of second sub-sections 1602 arranged obliquely relative to the first direction. The plurality of first sub-sections 1601 are arranged at intervals along the second direction, and the second sub-sections 1602 respectively connect the ends of two adjacent first sub-sections 1601 located on different sides thereof to form a "Z"-shaped reflection path 16. Figure 5 The embodiment shown is different in that Figure 7 In the illustrated embodiment, the emission control unit 182 is configured to control the light source module 122 to emit a light beam when the MEMS galvanometer module 126 deflects and reflects at a corresponding deflection angle along the first subsection 1601 of the light beam reflection path 16, and to stop emitting the light beam when the MEMS galvanometer module 126 deflects and reflects at a corresponding deflection angle along the second subsection 1602 of the light beam reflection path 16. In this case, the emission module 12 only forms a scanning path along the first subsection 1601 of the light beam reflection path 16 with respect to the MEMS galvanometer module 126. Figure 6 The solid line represents the scanning path of this part, and no actual scanning path of the light beam is formed on the second subsection 1602 of the light beam reflection path 16 by the MEMS galvanometer 126. Figure 6 The dotted line in FIG represents the partial reflection path 16. Thus, in Figure 6 In the illustrated embodiment, the actual scanning path of the light beam formed by the transmitting module 12 in the field of view is a plurality of first sub-sections 1601 in the light beam reflection path 16 of the MEMS galvanometer module 126 that are parallel to the first direction and spaced apart along the second direction.

[0094] The MEMS galvanometer module laser radar system 10 detects one frame of the entire field of view, including a scanning period corresponding to the actual scanning path of the light beam, that is, the scanning period corresponds to the reflection path 16 of the light beam by the MEMS galvanometer module 126, and the light source module 122 also synchronously emits the light beam to form the time period of the actual scanning path of the light beam. And the time period in which the light source module 122 does not synchronously emit the light beam in the reflection path 16 of the light beam by the one frame detection corresponding to the MEMS galvanometer module 126 can be defined as an intermittent period. Since the speed at which the reflection angle of the light beam is deflected along the first section 1601 by the MEMS galvanometer module 126 is significantly higher than the speed at which the light beam is deflected along the second section 1602, it takes a relatively long time for the light beam to be deflected from the field of view partition 13 at the end of the current first section 1601 to the field of view partition 13 at the starting end of the next first section 1601 through the MEMS galvanometer module 126. Figure 6 and Figure 7 In the embodiment, the time period during which the light beam scans all the field of view sub-areas 13 on a first sub-section 1601 can be defined as a scanning period. Multiple first sub-sections 1601 corresponding to the light beam scanning path form multiple scanning periods, and multiple second sub-sections 1602 corresponding to the beam reflection path 16 of the MEMS galvanometer module 126 that do not synchronously emit light beams form multiple pause periods. The pause period connects two adjacent scanning periods, corresponding to the connection between the first sub-sections 1601 and the second sub-sections 1602. The emission control unit 182 controls the light source module 122 to emit a light beam along the beam emission path 16 of the MEMS galvanometer module 126 during the scanning period to form the actual scanning path of the light beam. The emission control unit 182 controls the light source module 122 to stop emitting the light beam during the pause period.

[0095] The control module 18 may further include a sensing control unit 186 configured to control the corresponding photosensitive pixels 142 to operate in sequence and in a time-sharing manner according to the scanning direction of the light beam to receive light signals from the field of view subarea 13 currently scanned by the light beam. The sensing control unit 186 is configured to control the photosensitive pixels 142 to stop operating during the intermission period.

[0096] The multiple field of view sub-regions 13 sequentially distributed along a first sub-portion 1601 are in the same row of field of view sub-regions 13. The multiple photosensitive pixels corresponding to sensing the same row of field of view sub-regions 13 can be defined as a photosensitive pixel group. The multiple photosensitive pixel groups respectively sense the multiple rows of field of view sub-regions 13 sequentially arranged along the second direction. The sensing control unit 186 is configured to control the time-sharing operation of the photosensitive pixels 142 to be synchronized with the scanning direction of the light beam. The time-sharing operation order of the photosensitive pixels 142 within the same photosensitive pixel group is the same as the order in which the corresponding field of view sub-regions 13 in the same row are scanned along the first sub-portion 1601.

[0097] For example, in Figure 4 and Figure 6 In the embodiment shown, since the light beam is scanned along opposite scanning directions on the two adjacent first divisions 1601, the two sensing pixel groups for sensing the field of view partitions 13 on the two adjacent first divisions 1601 are also correspondingly arranged adjacent to each other on the photosensor 140, and the sensing control unit 186 controls the photosensitive pixels 142 in each of the two adjacently arranged photosensitive pixel groups to work in opposite order in time-sharing manner.

[0098] For example, in Figure 5 and Figure 7 In the embodiment shown, since the light beam is scanned along the same scanning direction on two adjacent first divisions 1601, the two sensing pixel groups for sensing the field of view partitions 13 on the two adjacent first divisions 1601 are also correspondingly arranged adjacent to each other on the photosensor 140, and the sensing control unit 186 is configured to control the photosensitive pixels within each of the two adjacently arranged photosensitive pixel groups to work in the same order and in a time-sharing manner.

[0099] The emission control unit 182 is further configured to control the light source module 122 to emit light beam pulses according to a preset timing sequence during a detection period corresponding to a field of view subarea 13. After the light beam is reflected along a preset reflection angle of the MEMS galvanometer module 126, the area illuminated by the field of view subarea 13 corresponding to the preset reflection angle.

[0100] In some embodiments, as Figure 8 As shown, the first subsection 1601 includes a middle section and first and second sections located on opposite sides of the middle section. The MEMS galvanometer module 126 deflects the light beam at a higher speed in the middle section than in the first and second sections. Therefore, the emission control unit 182 is further configured to adjust the parameters of the light beam emitted by the light source module 122 to compensate for the difference in total energy of the light beam emitted by the emission module 12 for the field of view subsections 13 in different orientations due to the change in the speed of the MEMS galvanometer module 126 deflecting the light beam along the first subsection 1601. The detection effect of three-dimensional information detection based on the dToF principle, such as detection accuracy, detection precision, and confidence, is related to the energy of the emitted light beam. Therefore, reducing the difference in light beam energy for the field of view subsections 13 in different orientations can reduce the difference in detection effect for the field of view subsections 13 in different orientations. Correspondingly, the sensing control unit 186 is configured to control the operating time of different photosensitive pixels 142 within the same photosensitive pixel group to first shorten and then increase in sequence according to the order in which they are activated in a time-sharing manner. That is, the sensing control unit 186 controls the working time of the photosensitive pixels 142 corresponding to the first and second sensing segments in the same photosensitive pixel group to be longer than the working time of the photosensitive pixels 142 corresponding to the middle sensing segment.

[0101] Optionally, the parameters of the light beam emitted by the light source module 122 include but are not limited to the frequency of the emitted light beam, the power of the emitted light beam, and the total number of times the light beam is emitted to the corresponding field of view partition 13 within a partition detection period. The emission control unit 182 can compensate for the difference in total energy of the light beam emitted by the emission module 12 to different field of view partitions 13 due to the change in the speed of the MEMS galvanometer module 126 deflecting the light beam along the first division 1601 by controlling one or more of the above-mentioned different parameters.

[0102] It should be understood that the total energy of the light beam emitted by the transmitting module 12 for the field of view partitions 13 in different directions on the first division 1601 will be set to be different in response to different application scenarios. For example, for the main vehicle-mounted laser radar, the middle field of view partition 13 is required to be measured relatively far away, so the total energy of the light beam emitted by the transmitting module 12 for the middle field of view partition 13 is relatively high. Therefore, the above-mentioned transmitting control unit 182 adjusts the parameters of the light beam emitted by the light source module 122 to compensate for the difference in the total energy of the light beam emitted by the transmitting module 12 for different field of view partitions 13 due to the change in the speed of the deflection light beam of the MEMS galvanometer module 126, which deviates from the original preset value, and does not mean that the total energy of the light beam emitted by the transmitting module 12 for different field of view partitions 13 is compensated to be consistent with each other.

[0103] Specifically, in Figure 8 In some of the illustrated embodiments, the emission control unit 182 may be configured to control the light source module 122 to emit a light beam at a higher frequency when scanning the middle segment than when scanning the first and second segments. This can compensate for the difference in the number of light beam pulses emitted to the middle segment field of view partition 13 and to the first and second segment field of view partitions 13 caused by the relatively short time the emission module 12 emits the light beam to the middle segment field of view partition 13. When the emission power of each light beam pulse is the same, the error caused by the total energy of the emitted light beam deviating from a preset value due to the relatively short time the light beam is emitted to the middle segment field of view partition 13 can be compensated, thereby improving the detection accuracy of the MEMS galvanometer laser radar system 10.

[0104] Specifically, in Figure 9In some of the illustrated embodiments, the emission control unit 182 can be configured to control the light source module 122 to emit a higher power beam when scanning the middle segment than when scanning the first and second segments. When the light source module 122 uses the same beam emission frequency to detect different field of view subareas 13, the relatively short time for the emission module 12 to emit a beam to the middle field of view subarea 13 can result in the number of beam pulses emitted to the middle field of view subarea 13 during detection being less than the number of beam pulses emitted to the first and second field of view subareas 13. Therefore, setting the power of the beam emitted by the light source module 122 to be higher for the middle field of view subarea 13 than for the first and second field of view subareas 13 during detection can compensate for errors caused by the total energy of the beams emitted to different field of view subareas 13 deviating from a preset value due to this situation, thereby improving the detection accuracy of the MEMS galvanometer lidar system 10.

[0105] Optionally, in some embodiments, since the light energy loss of the light beam passing through the deflection angle magnification module 128 is proportional to the deflection angle of the light beam after passing through the deflection angle magnification module 128, the deflection angle of the light beam corresponding to the first segment field of view partition 13 and the second segment field of view partition 13 on the first division 1601 after passing through the deflection angle magnification module 128 is larger than the deflection angle of the light beam scanning the middle segment field of view partition 13 after passing through the deflection angle magnification module 128, so the light energy loss generated by the light beam scanning the first segment field of view partition 13 and the second segment field of view partition 13 passing through the deflection angle magnification module 128 will be greater than the light energy loss generated by the light beam corresponding to the scanning the middle segment field of view partition 13 passing through the deflection angle magnification module 128. Therefore, in order to compensate for the difference in light energy loss caused by the deflection angle amplification module 128 to light beams with different deflection angles so as to improve the detection accuracy of the MEMS galvanometer lidar system 10, the emission control unit 182 can be configured to control the light source module 122 to emit a light beam less times during the detection of a field of view partition 13 located in the middle segment than the number of times the light beam is emitted during the detection of a field of view partition 13 located in the first segment and the second segment.

[0106] Correspondingly, in some embodiments, the control module 18 further includes a data processing control unit 188. The data processing control unit 188 is configured to control the processing module 15 to analyze and process the relevant data of the field of view sub-area 13 that has been inspected in the previous first sub-section 1601 during the intermittent period to obtain corresponding three-dimensional information. By processing the data generated from the previous inspection of the field of view sub-area 13 of the first sub-section 1601 during the intermittent period of cessation of inspection, the data processing efficiency of the MEMS galvanometer lidar system 10 can be improved, while further reducing the storage medium 30 used for caching data, thereby reducing the hardware cost of the MEMS galvanometer lidar system 10.

[0107] In some embodiments, the deflection angle magnification module 128 can be a lens group, for example, including a first lens 1281 and a second lens 1282. The first lens 1281 and the second lens 1282 are arranged sequentially along the propagation direction of the light beam. The optical axes of the first lens 1281 and the second lens 1282 both coincide with the center direction of the field of view. The focal point of one side of the first lens 1281 and the focal point of one side of the second lens 1282 are arranged to coincide with each other in the section between the first lens 1281 and the second lens 1282. That is, the light beam reflected and deflected by the MEMS galvanometer module 126 is first converged by the first lens 1281 onto the focal plane of the second lens 1282, and then deflected by the second lens 1282 to achieve amplification of the deflection angle.

[0108] For example, in Figure 10 In the illustrated embodiment, both the first lens 1281 and the second lens 1282 have positive optical power. If the focal length of the first lens 1281 is F1 and the focal length of the second lens is F2, then the deflection angle magnification factor M of the light beam deflection angle by the deflection angle magnification module 128 is M = F1 / F2. In other words, the angle of the light beam deflected from the center of the field of view by the MEMS galvanometer module 126 before entering the deflection angle magnification module 128 will be magnified M times after passing through the deflection angle magnification module 128.

[0109] For example, in Figure 11 In the embodiment shown, the first lens 1281 has positive optical focal length, and the second lens 1282 has negative optical focal length. If the focal length of the first lens 1281 is F1, and the focal length of the second lens is F2, then the deflection angle magnification factor of the light beam deflection angle by the deflection angle magnification module 128 is M=F1 / F2, that is, the angle of the light beam deviating from the center direction of the field of view range after being reflected by the MEMS galvanometer module 126 before entering the deflection angle magnification module 128 will be magnified M times after passing through the deflection angle magnification module 128.

[0110] It should be understood that the first lens 1281 can be a single lens or a lens group including multiple lenses. Similarly, the second lens 1282 can be a single lens or a lens group including multiple lenses.

[0111] It should be understood that the first lens 1281 and the second lens 1282 can both be spherical mirrors that are rotationally symmetric about the optical axis and are configured to magnify the deflection angle of the passing light beam in all directions by the same factor. For example, the first lens 1281 and the second lens 1282 can magnify the deflection angle of the passing light beam by M times in both the first direction and the second direction, where the first direction is perpendicular to the second direction.

[0112] The number N1 (also called the number of distinguishable points) of the light beam reflection angles deflected by the MEMS galvanometer module 126 along the first direction, the frequency f1 of the light beam reflection angles deflected by the MEMS galvanometer module 126 along the first direction, and the minimum number of light beam pulses that the MEMS galvanometer laser radar system 10 needs to emit for one reflection angle along the first direction are: and the time interval ΔT between two consecutive beam pulses x Related, as shown in the relationship:

[0113]

[0114] It should be understood that, since the number of light beam pulses emitted by the MEMS galvanometer laser radar system 10 corresponding to different reflection angles along the first direction may be different, It refers to the minimum value of the number of light beam pulses emitted at each reflection angle deflected along the first direction.

[0115] The deflection angle N2 of the MEMS galvanometer module 126 deflecting the light beam reflection angle along the second direction is related to the frequency f1 of the MEMS galvanometer module 126 deflecting the light beam reflection angle along the first direction and the frequency f2 of the MEMS galvanometer module 126 deflecting the light beam reflection angle along the second direction, specifically, as shown in the following relationship:

[0116]

[0117] If the angle range of the light beam emitted by the MEMS galvanometer laser radar system 10 that can be deflected along the first direction is θ1, and the angle range of the light beam that can be deflected along the second direction is θ2, then the expression of the angular resolution δθ1 of the reflection angle of the light beam deflected along the first direction by the MEMS galvanometer laser radar system 10 is:

[0118]

[0119] Wherein, f1 is the frequency of the MEMS galvanometer module 126 deflecting the light beam reflection angle along the first direction, is the minimum number of beam pulses that the MEMS galvanometer laser radar system 10 needs to emit at a reflection angle along the first direction and ΔT x is the time interval between two consecutive beam pulses, The time required for the MEMS galvanometer laser radar system 10 to complete a detection at one of the reflection angles deflected along the first direction. The expression for the angular resolution δθ2 of the reflection angle of the light beam deflected along the second direction by the MEMS galvanometer laser radar system 10 is:

[0120]

[0121] Wherein, f1 is the frequency of the MEMS galvanometer module 126 deflecting the light beam reflection angle along the first direction, and f2 is the frequency of the MEMS galvanometer module 126 deflecting the light beam reflection angle along the second direction.

[0122] It should be understood that the first direction refers to the direction in which the MEMS galvanometer module 126 deflects the reflection angle of the light beam at a faster speed, which can also be called the fast axis direction of the MEMS galvanometer module 126, corresponding to the first division 1601 in the reflection path 16 of the light beam by the MEMS galvanometer module 126; the second direction refers to the direction in which the MEMS galvanometer module 126 deflects the reflection angle of the light beam at a slower speed, which can also be called the slow axis direction of the MEMS galvanometer module 126, corresponding to the second division 1602 in the reflection path 16 of the light beam. The field of view partitions 13 for time-sharing scanning of the light beam in the field of view range are arranged along the first direction. The field of view partitions 13 of different rows are arranged along the second direction; or, the second direction connects the field of view partitions 13 located at the ends of adjacent different rows.

[0123] Optionally, in some embodiments, the first direction is perpendicular to the second direction. For example, the first direction is horizontal and the second direction is vertical; or the first direction is vertical and the second direction is horizontal.

[0124] When performing light beam scanning, the deflection control unit 184 controls the MEMS galvanometer module 126 to sequentially change the different reflection angles of the light beam along the reflection path of the light beam at different time periods. The emission control unit 182 controls the light source module 122 to emit a light beam corresponding to the preset reflection angle on the reflection path to form a corresponding scanning path within the field of view. For the preset reflection angle of the light beam within the field of view, the emission control unit 182 controls the light source module 122 to emit a light beam pulse to the corresponding field of view partition 13 along the preset reflection angle according to a preset time sequence. In order to make the time-correlated single photon counting method used in dToF measurement have mathematical statistical significance, the emission control unit 182 controls the corresponding light source module 122 to emit multiple light beam pulses according to a preset time sequence within the partition detection period of detecting a field of view partition 13, such as: dozens, hundreds, thousands, tens of thousands, or even millions. The emission of a light beam pulse corresponds to a sensing period, that is, a partition detection period includes multiple sensing periods. Correspondingly, the sensing control unit 186 controls the photosensitive pixels 142 corresponding to the currently detected field of view partition 13 to start working in a time-sharing manner to sense the light signal from the field of view partition 13 and thereby obtain the three-dimensional information of the field of view partition 13 .

[0125] In some embodiments, all or part of the functional units in the control module 18 and / or the processing module 15 may include firmware solidified in the storage medium 30 or computer software code stored in the storage medium 30, and executed by one or more corresponding processors 40 to control related components to implement corresponding functions. The processor 40 is, for example, but not limited to, an application processor (AP), a central processing unit (CPU), a microcontroller unit (MCU), etc. The storage medium 30 includes, but is not limited to, flash memory, electrically erasable programmable read only memory (EEPROM), programmable read only memory (PROM), a hard disk, etc.

[0126] In some embodiments, the processor 40 and / or storage medium 30 may be disposed within the MEMS galvanometer lidar system 10, for example, integrated on the same circuit board as the transmitting module 12 or the receiving module 14. Alternatively, in other embodiments, the processor 40 and / or storage medium 30 may be disposed elsewhere within the electronic device 1, for example, on a main circuit board of the electronic device 1.

[0127] In some embodiments, part or all of the functional units of the control module 18 and / or the processing module 15 may also be implemented by hardware means, for example, by any one of the following technologies or a combination thereof: a discrete logic circuit having a logic gate circuit for implementing logical functions on data signals, a dedicated integrated circuit having a suitable combinational logic gate circuit, a programmable gate array (PGA), a field programmable gate array (FPGA), a driving circuit for a specific object, etc.

[0128] It is understandable that different functional units of the control module 18 and / or a portion of the processing module 15 may respectively include related hardware. For example, the emission control unit 182 may include a driving circuit of the light source module 122 .

[0129] It is understandable that the hardware used to implement the functions of the control module 18 and / or the processing module 15 can be set in the MEMS galvanometer lidar system 10. The hardware used to implement the functions of the control module 18 and / or the processing module 15 can also be set in other locations of the electronic device 1, such as: on the main circuit board of the electronic device 1.

[0130] like Figure 12 As shown, in some embodiments, the MEMS galvanometer laser radar system 10 is, for example, a laser radar, and the electronic device 1 is, for example, a car. The laser radar can be installed at multiple different locations on the car to detect distance information of objects within the car's surrounding range and implement driving control accordingly.

[0131] Compared with the laser radar that uses mechanical rotation to achieve light beam scanning, the laser radar provided in this application uses a semi-solid MEMS galvanometer module 126 to achieve light beam deflection scanning. Since it no longer needs to rely on mechanical rotating parts, it has higher reliability and a more compact structure, is easier to pass strict vehicle regulations, and has less impact on the appearance of the car.

[0132] It should be noted that the technical solution to be protected by this application may satisfy only one of the above embodiments or multiple embodiments at the same time. That is to say, the embodiment composed of one or more of the above embodiments also falls within the scope of protection of this application.

[0133] Throughout this specification, reference to terms such as "one embodiment," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0134] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A MEMS galvanometer laser radar system, characterized in that: It is configured to sense three-dimensional information of a field of view along a preset scanning path, including: Transmitter module, including: The MEMS galvanometer module is configured to sequentially deflect different reflection angles of the light beam along a first direction and a second direction at different time periods, wherein the deflection trajectory of the reflection angle is defined as a reflection path of the light beam by the MEMS galvanometer module, wherein the reflection path includes a plurality of first subsections and a plurality of second subsections connecting different first subsections, wherein the first subsections are line segments parallel to the first direction, and the plurality of first subsections are arranged parallel to each other and spaced apart in sequence along the second direction; a light source module configured to emit a light beam; and A deflection angle magnification module is configured to magnify the deflection angle of the light beam reflected by the MEMS galvanometer module in the corresponding deflection direction by a preset multiple; The receiving module is configured to sense the optical signal from the field of view, including: A photosensor comprising a plurality of light-sensitive pixels configured to respond to light signals and output corresponding light-sensing signals; and A receiving optical device is configured to transmit light signals from different directions within the field of view to corresponding photosensitive pixels respectively; a processing module configured to process the light sensing signal to obtain three-dimensional information; and The control module is configured to control the MEMS galvanometer module to deflect the reflection angle of the light beam in sequence, control the light source module to emit the light beam at the reflection angle corresponding to the scanning path, and control the corresponding photosensitive pixels to work in sequence and time-sharing according to the scanning direction of the light beam. The first section includes a middle section and a first section and a second section located on opposite sides of the middle section, and the control module is configured to control the light source module to emit a light beam with a power higher than that of the light beam when scanning the middle section.

2. The MEMS galvanometer laser radar system according to claim 1, wherein: The photosensitive pixel includes at least one photoelectric conversion device.

3. The MEMS galvanometer laser radar system according to claim 2, wherein: The photoelectric conversion device may be any one or more combinations of a single photon avalanche diode, an avalanche photodiode, or a silicon photomultiplier tube.

4. The MEMS galvanometer laser radar system according to claim 1, wherein: The first direction and the second direction are perpendicular to each other, the first direction is a horizontal direction, and the second direction is a vertical direction; or, The first direction is a vertical direction, and the second direction is a horizontal direction.

5. The MEMS galvanometer laser radar system according to claim 1, wherein: The second subsection is a line segment parallel to the second direction, and the second subsection connects ends of two adjacent first subsections located on the same side, and the deflection directions of the reflection angles of the light beam on the two adjacent first subsections are opposite; or, The second section is a line segment tilted relative to the first direction. The second section connects ends of two adjacent first sections on different sides. The deflection directions of the reflection angles of the light beams on the two adjacent first sections are the same.

6. The MEMS galvanometer laser radar system according to claim 1, wherein: The first section includes a middle section and a first section and a second section located on opposite sides of the middle section. The MEMS galvanometer module is configured to deflect the light beam reflection angle at a higher speed in the middle section than in the first section and the second section.

7. The MEMS galvanometer laser radar system according to claim 6, wherein: The first section includes a middle section and a first section and a second section located on opposite sides of the middle section. The control module is configured to control the light source module to emit a light beam at a frequency higher than that of the light beam when scanning the middle section.

8. The MEMS galvanometer laser radar system according to claim 1, wherein: The first section includes a middle section and a first section and a second section located on opposite sides of the middle section. The control module is configured to control the light source module to emit a light beam less times when scanning the middle section than when scanning the first section and the second section.

9. The MEMS galvanometer laser radar system according to claim 1, wherein: The deflection angle magnification module includes a lens group having a plurality of lenses; or, The deflection angle magnification module includes a super lens.

10. An electronic device, characterized in that: The electronic device comprises the MEMS galvanometer laser radar system as described in any one of claims 1 to 9, and further comprises an application module, wherein the application module is configured to implement corresponding functions according to the detection results of the MEMS galvanometer laser radar system.

Images