MEMS Galvanometer LiDAR System and Electronic Device

Abstract

The present application provides a MEMS galvanometer laser radar system, including: a transmitting module, a receiving module, a processing module and a control module. The transmitting module includes a MEMS galvanometer module, a light source module and a deflection angle magnification module. The MEMS galvanometer module deflects different reflection angles of the light beam in sequence in time-sharing. The light source module emits a light beam corresponding to the reflection angle where the scanning path is located. The deflection angle magnification module amplifies the deflection angle of the light beam in the corresponding deflection direction after reflection and deflection by a preset multiple. The receiving module includes a photoelectric sensor and a receiving optical device, and the receiving optical device transmits light signals from different directions of the field of view to the corresponding photosensitive pixels on the photoelectric sensor. The processing module is used to obtain three-dimensional information based on the light sensing signals output by the photosensitive pixels. The control module controls the corresponding photosensitive pixels to work in sequence in time-sharing according to the scanning direction of the light beam. The present application also provides an electronic device including a MEMS galvanometer laser radar system.

Description

Technical Field

[0001] This application belongs to the field of optoelectronic detection, and particularly relates to a MEMS galvanometer lidar system and an electronic device that achieve beam deflection through a MicroElectromechanical System (MEMS) galvanometer. Background Art

[0002] The ranging function of lidar is usually based on the Time of Flight (ToF) measurement principle, that is, by emitting laser pulses to the measurement scene and measuring the round-trip flight time of the laser pulses between the lidar and the target object to calculate three-dimensional information such as the distance of the target object. Due to the advantages of long sensing distance, high accuracy, and low energy consumption of ToF measurement, it is widely used in consumer electronics, intelligent driving, unmanned aerial vehicles, AR / VR and other fields.

[0003] The field of view angle covered by a single beam emitted by a detection device using the ToF measurement principle for ranging is limited, and a larger field of view range needs to be obtained by continuously changing the beam irradiation direction through scanning. Currently, a commonly used method to change the beam emission direction mainly realizes it by mechanically rotating the emission module and the reception module of the detection device. However, this method often requires multiple discrete devices to be assembled into a mechanical rotation structure, with high complexity in optical path debugging and assembly of emission / reception, and the mechanical rotation structure is also prone to damage and misalignment. Moreover, due to the large size of the mechanical rotation structure, it will affect the shape of the terminal device using it. Summary of the Invention

[0004] In view of this, this application provides a MEMS galvanometer lidar system and related electronic devices that can improve the problems of the prior art.

[0005] In a first aspect, this application provides a MEMS galvanometer lidar system configured to sense three-dimensional information for a field of view range along a preset scanning path, including:

[0006] An emission module, including:

[0007] A MEMS galvanometer module configured to deflect different reflection angles of the beam in different time periods in sequence;

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

[0009] A deflection angle amplification module configured to amplify the deflection angle of the beam reflected by the MEMS galvanometer module in the corresponding deflection direction by a preset multiple;

[0010] A reception module configured to sense optical signals from the field of view range, including:

[0011] A photoelectric sensor, including a plurality of photosensitive pixels, is configured to respond to an optical signal and output a corresponding optical induction signal; and

[0012] A receiving optical device is configured to transmit optical signals from different azimuths within a field of view range to corresponding photosensitive pixels respectively;

[0013] A processing module is configured to process the optical induction signal to obtain three-dimensional information; and

[0014] A control module is configured to control the MEMS galvanometer module to sequentially deflect the reflection angle of a light beam, control the light source module to emit a light beam corresponding to the reflection angle where the deflection path is located, and control the corresponding photosensitive pixels to work in sequence and time division according to the scanning azimuth of the light beam.

[0015] In a second aspect, the present application provides an electronic device, including an application module and the MEMS galvanometer lidar system as described above. The application module is configured to implement corresponding functions according to the detection results of the MEMS galvanometer lidar system.

[0016] Advantages of the present application:

[0017] Compared with realizing the deflection of a light beam through a mechanical rotation scheme and a hybrid solid-state scheme, the present application realizes two-dimensional deflection scanning of the light beam through the MEMS galvanometer module within a preset deflection angle range, does not need to rely on easily damaged and bulky rotating components, and has the beneficial effects of better reliability and compact size. Description of the drawings

[0018] By referring to the drawings and describing its exemplary embodiments in detail, the features and advantages of the present invention will become more obvious.

[0019] Figure 1 It is a schematic diagram of the functional modules of an electronic device provided by an embodiment of the present application;

[0020] Figure 2 For Figure 1 It is a schematic diagram of the functional modules of an embodiment of the MEMS galvanometer lidar system described in

[0021] Figure 3 For Figure 2 It is a schematic diagram of the optical path of the emission module of the MEMS galvanometer lidar system described in

[0022] Figure 4 It is a schematic diagram of the light beam scanning path of the MEMS galvanometer lidar system provided by an embodiment of the present application;

[0023] Figure 5Schematic diagram of the beam scanning path of the MEMS galvanometer lidar system provided by an embodiment of the present application;

[0024] Figure 6 Schematic diagram of the beam scanning path of the MEMS galvanometer lidar system provided by an embodiment of the present application;

[0025] Figure 7 Schematic diagram of the beam scanning path of the MEMS galvanometer lidar system provided by an embodiment of the present application;

[0026] Figure 8 Schematic diagram showing the variation of the frequency of the emitted beam of the MEMS galvanometer lidar system provided by an embodiment of the present application with the scanning path;

[0027] Figure 9 Schematic diagram showing the variation of the power of the emitted beam of the MEMS galvanometer lidar system provided by an embodiment of the present application with the scanning path;

[0028] Figure 10 For Figure 3 Optical path schematic diagram of an embodiment of the deflection angle amplification module of the emission module described in

[0029] Figure 11 For Figure 3 Optical path schematic diagram of an embodiment of the deflection angle amplification module of the emission module described in

[0030] Figure 12 Schematic diagram of the structure of the MEMS galvanometer lidar system provided by an embodiment of the present application as an automotive lidar. Detailed implementation mode

[0031] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present application and should not be construed as a limitation of 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 cannot be construed as indicating or implying relative importance or implicitly specifying the quantity or arrangement order of the indicated technical features. Thus, the technical features defined with "first" and "second" may explicitly or implicitly include one or more of the said technical features. In the description of the present application, "a plurality" means two or more unless otherwise specifically defined.

[0032] In the description of the present application, it should be noted that, unless otherwise clearly specified or limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0033] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, only the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present application. In addition, the present application may reuse reference numerals and / or reference letters in different examples. Such reuse is for the purpose of simplifying and clearly expressing 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 following description of the present application are only examples for implementing the technical solution of the present application. However, those of ordinary skill in the art should realize that the technical solution of the present application can also be implemented by other processes and / or other materials not described below.

[0034] Furthermore, the described features and structures can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to enable a full understanding of the embodiments of the present application. However, those skilled in the art should realize that even without one or more of the specific details, or by using other structures, components, etc., the technical solution of the present application can still be practiced. In other cases, well-known structures or operations are not shown or described in detail to avoid obscuring the focus of the present application.

[0035] An embodiment of the present application provides a MEMS galvanometer lidar system configured to sense three-dimensional information within a field of view along a preset scanning path, including:

[0036] A transmitting module, including:

[0037] A MEMS galvanometer module configured to deflect different reflection angles of a light beam in sequence at different time intervals;

[0038] A light source module configured to emit a light beam corresponding to the reflection angle where the scanning path is located; and

[0039] A deflection angle amplification module configured to amplify the deflection angle of the light beam reflected by the MEMS galvanometer module in the corresponding deflection direction by a preset multiple;

[0040] A receiving module, configured to sense optical signals from the field of view, includes:

[0041] An optoelectronic sensor, including a plurality of photosensitive pixels, configured to respond to the optical signals and output corresponding photoinduction signals; and

[0042] A receiving optical device, configured to transmit optical signals from different azimuths in the field of view to corresponding photosensitive pixels respectively;

[0043] A processing module, configured to process the photoinduction signals to obtain three-dimensional information; and

[0044] A control module, 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 a light beam corresponding to the reflection angle where the deflection path is located, and control the corresponding photosensitive pixels to work sequentially and time-divisionally according to the scanning azimuth of the light beam. The three-dimensional information is, for example: proximity information of an object within the field of view, depth information of the object surface, coordinate information of the object within the field of view, and corresponding distance information, etc. Among them, the three-dimensional information can be used, for example, in fields such as 3D modeling, identity recognition, autonomous driving, machine vision, monitoring, drone control, augmented reality (AR) / virtual reality (VR), simultaneous localization and mapping (SLAM), object proximity determination, etc. This application does not limit this.

[0045] In some embodiments, the photosensitive pixel includes at least one optoelectronic conversion device.

[0046] In some embodiments, the optoelectronic conversion device can be any one or a combination of a single-photon avalanche diode, an avalanche photodiode, or a silicon photomultiplier.

[0047] In some embodiments, the MEMS galvanometer module is a two-dimensional MEMS galvanometer module, configured to change the reflection angle of the light beam along a first direction and a second direction, and the first direction and the second direction are perpendicularly arranged to each other.

[0048] In some embodiments, the first direction is the horizontal direction and the second direction is the vertical direction; or, the first direction is the vertical direction and the second direction is the horizontal direction.

[0049] 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 a plurality of first segments and a plurality of second segments connecting different first segments. The first segment is a line segment parallel to the first direction, and the plurality of first segments are arranged parallel to each other and are sequentially spaced along the second direction.

[0050] In some embodiments, the second segment is a line segment parallel to the second direction, and the second segment respectively connects the ends of two adjacent first segments on the same side, and the deflection directions of the reflection angles of the light beam on two adjacent first segments are opposite; or, the second segment is a line segment inclined with respect to the first direction, and the second segment respectively connects the ends of two adjacent first segments on different sides, and the deflection directions of the reflection angles of the light beam on two adjacent first segments are the same.

[0051] In some embodiments, the detection of one frame in the entire field of view includes a plurality of 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 and sensing along one of the first segments during a 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 perform scanning and sensing on the next first segment during the intermittent period, and control the light source module to stop emitting the light beam during the intermittent period.

[0052] In some embodiments, the control module is configured to control the processing module to process the photoinduction signal data obtained by scanning and sensing the previous first segment during the intermittent period.

[0053] In some embodiments, the first segment includes a middle section and a first section and a second section respectively located on opposite sides of the middle section, and the MEMS galvanometer module is configured to deflect the reflection angle of the light beam at a higher speed in the middle section than in the first section and the second section.

[0054] In some embodiments, the first segment includes a middle section and a first section and a second section respectively located on opposite sides of the middle section, and the control module is configured to control the light source module to emit the light beam at a higher frequency when scanning the middle section than when scanning the first section and the second section.

[0055] In some embodiments, the first segment includes a middle section and a first section and a second section respectively located on opposite sides of the middle section, and the control module is configured to control the light source module to emit the light beam at a higher power when scanning the middle section than when scanning the first section and the second section.

[0056] In some embodiments, the first segment includes a middle section and a first section and a second section respectively located on opposite sides of the middle section, and the control module is configured to control the light source module to emit the light beam a lower number of times when scanning the middle section than when scanning the first section and the second section.

[0057] In some embodiments, the deflection angle amplification module includes a lens group having a plurality of lenses; alternatively, the deflection angle amplification module includes a metasurface lens.

[0058] Embodiments of the present application further provide an electronic device, which includes the MEMS galvanometer lidar system. The electronic device realizes corresponding functions according to the three-dimensional information obtained by the MEMS galvanometer lidar system. The electronic device is, for example: a mobile phone, an automobile, a robot, an access control / monitoring system, a smart door lock, an unmanned mobile vehicle, an aircraft, etc. Taking an intelligent driving vehicle as an example, setting a MEMS galvanometer lidar system in the intelligent driving vehicle can scan the surrounding environment by rapidly and repeatedly emitting laser pulses as light beams to obtain point cloud data on the morphology, position, and motion of objects within the field of view.

[0059] Hereinafter, embodiments of applying the MEMS galvanometer lidar system to an electronic device will be described in detail with reference to the accompanying drawings.

[0060] Figure 1 It is a schematic diagram of the functional modules of the MEMS galvanometer lidar system applied to an electronic device provided by an embodiment of the present application. Figure 2 It is a schematic diagram of the functional modules of the MEMS galvanometer lidar system provided by an embodiment of the present application.

[0061] Referring to Figure 1 and Figure 2 , the electronic device 1 includes a MEMS galvanometer lidar system 10. The MEMS galvanometer lidar system 10 is configured to sense three-dimensional information along a preset scanning path within a field of view, and the field of view can be defined as the three-dimensional space range within which the MEMS galvanometer lidar system 10 can effectively detect three-dimensional information, and can also be referred to as the field of view angle or field of view range of the MEMS galvanometer lidar system 10.

[0062] The electronic device 1 may include an application module 20, which is configured to perform a preset operation or implement a corresponding function according to the detection result of the MEMS galvanometer lidar system 10. For example, but not limited to: judging whether an object 2 appears within a preset field of view in front of the electronic device 1 according to the proximity information of the object 2; or, controlling the movement of the electronic device 1 for obstacle avoidance or navigation, 3D modeling, machine vision, etc. according to the distance information and azimuth information of the object 2 within the field of view; or, realizing identity recognition according to the depth information on the surface of the object 2. That is to say, the application module 20 can be a set including the hardware required to perform the above operations and implement the above functions and the software required to control and coordinate the operation of the hardware.

[0063] The electronic device 1 may further include a storage medium 30, and the storage medium 30 may support the storage requirements of the electronic device 1 and / or the MEMS galvanometer lidar system 10 during operation. As Figure 1 shown, in some embodiments, the storage medium 30 may be disposed inside the electronic device 1. As Figure 2 shown, in some embodiments, the storage medium 30 may also be disposed inside the MEMS galvanometer lidar system 10.

[0064] The electronic device 1 may further include a processor 40, which may support the data processing requirements of the electronic device 1 and / or the MEMS galvanometer lidar system 10 during operation. As Figure 1 shown, in some embodiments, the processor 40 may be disposed inside the electronic device 1. As Figure 2 shown, in some embodiments, the processor 40 may also be disposed inside the MEMS galvanometer lidar system 10.

[0065] Optionally, in some embodiments, the MEMS galvanometer lidar system 10 may, for example, perform three-dimensional information sensing based on the direct Time of Flight (dToF) principle. By emitting a light beam within the field of view and receiving the light beam reflected back by an object 2 within the field of view, the time difference between the emission time and the reception time of the reflected light beam is referred to as 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 during the flight time t where c is the speed of light.

[0066] In some other embodiments, the MEMS galvanometer lidar system 10 may also perform three-dimensional information sensing based on the indirect Time of Flight (iToF) measurement principle, and obtain the three-dimensional information of the object 2 by comparing the phase difference between when the light beam is emitted and when it is reflected back and received.

[0067] In some other embodiments, the MEMS galvanometer lidar system 10 may also perform three-dimensional information sensing based on the Frequency Modulated Continuous Wave (FMCW) measurement principle. By interfering the returned light and the emitted light, and using the heterodyne detection technology to measure the frequency difference between the transmission and reception, and then converting the frequency difference to calculate the distance of the target object.

[0068] In the following embodiments of the present application, the MEMS galvanometer lidar system 10 is mainly described by taking the dToF measurement principle as an example.

[0069] In some embodiments, as Figure 2 shown, the MEMS galvanometer lidar system 10 includes a transmitting module 12, a receiving module 14, and a processing module 15. The transmitting module 12 is configured to emit a light beam into the field of view and deflect the irradiation direction of the light beam in a time-division manner according to a preset scanning path to achieve scanning of the entire field of view. A part of the light beam is reflected by the object 2 and returns. The reflected light beam echo carries the three-dimensional information of the object 2. A 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 optical signal from the field of view and output a corresponding optical induction signal. By analyzing the optical induction signal, the three-dimensional information detection of the object 2 within the field of view can be performed. It can be understood that the optical signal sensed by the receiving module 14 may include the light beam echo reflected by the object 2 within the field of view, or may include the ambient light within the field of view. The processing module 15 is configured to analyze and process the optical induction signal to obtain the moment when the light beam echo is sensed by the receiving module 14. For example, the optical induction signal is processed and analyzed based on the Time-Correlated Single Photon Counting (TCSPC) technique to obtain the moment when the light beam echo is sensed by constructing a photon counting histogram. On this basis, the processing module 15 is further configured to obtain the three-dimensional information of the field of view according to the time difference between the emission moment of the light beam and the sensed moment after reflection.

[0070] The processing module 15 may be disposed on the MEMS galvanometer lidar system 10, for example, disposed within 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 may also be disposed on the electronic device 1.

[0071] In some embodiments, the light beam can be, for example, a plurality of laser pulses emitted in sequence. 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 scans the field-of-view partitions 13 located at different azimuths within the field of view in a time-sharing manner along a preset scanning path, and emits a plurality of light beam pulses to the scanned field-of-view partitions 13 according to the corresponding preset time sequence for three-dimensional information detection. After emitting a plurality of light beam pulses to one field-of-view partition 13 and analyzing the time distribution of the optical signals sensed by the receiving module 14, the three-dimensional information of this field-of-view partition 13 can be correspondingly obtained. This process can be regarded as a partition detection period. After sequentially scanning each of the plurality of field-of-view partitions 13 once, it is regarded as completing one frame of detection for the entire field of view, and the three-dimensional information of all the field-of-view partitions 13 in the entire field of view can be correspondingly obtained, which can be used to construct a point cloud of one frame of the entire field of view. That is to say, a detection frame of the field of view includes a plurality of partition detection periods respectively corresponding to the scans of all the field-of-view partitions 13 within the field of view.

[0072] Optionally, the light beam is, for example, visible light, infrared light or near-infrared light, and the wavelength range is, for example, 390 nanometers (nm) - 780 nm, 700 nm - 1400 nm, 800 nm - 1000 nm, 900 nm - 1600 nm, etc.

[0073] It should be understood that the emission module 12 and the receiving module 14 are arranged side by side, and an off-axis optical path is used for emission and sensing. The light-emitting surface of the emission module 12 and the light-incident surface of the receiving module 14 both face the same side of the MEMS galvanometer lidar system 10. The distance range between the emission module 12 and the receiving module 14 can be, for example, 2 millimeters (mm) to 20 mm. Since the emission module 12 and the receiving module 14 are relatively close to each other, although the emission path of the light beam from the emission module 12 to the object 2 and the return path after reflection from the object 2 to the receiving module 14 are not exactly equal, both are much larger than the distance between the emission module 12 and the receiving module 14 and can be regarded as approximately equal. Thus, the distance between the object 2 and the MEMS galvanometer lidar system 10 can be calculated based on half of the flight time t of the light beam reflected by the object 2 multiplied by the speed of light c.

[0074] In some embodiments, such 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 disposed on the light incident side of the photoelectric sensor 140 and is configured to propagate light signals from different azimuths within the field of view to 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 in the figure). Optionally, the receiving lens may include one lens or multiple lenses. The photoelectric sensor 140 is configured to sense the light signals propagated from the field of view by the receiving optical device 144 and output corresponding light sensing signals.

[0075] In some embodiments, the receiving module 14 may further include a peripheral circuit (not shown in the figure) composed of one or more of devices such as a signal amplifier and an analog-to-digital converter (ADC), and the peripheral circuit may be partially or fully integrated in the photoelectric sensor 140.

[0076] The photoelectric sensor 140 may include a single photosensitive pixel 142 or multiple photosensitive pixels 142. The multiple photosensitive pixels 142 may be arranged in a two-dimensional array to form a photosensitive pixel array. The field of view range of the MEMS galvanometer lidar system 10 includes multiple field of view partitions 13 located in different orientations respectively. The multiple photosensitive pixels 142 are configured to have a preset corresponding relationship with the multiple field of view partitions 13. The optical signal returned from one of the field of view partitions 13 can be propagated through the receiving optical device 144 to the corresponding one or more photosensitive pixels 142 for sensing. That is, the field of view partition 13 corresponding to the photosensitive pixel 142 can be regarded as the field of view formed by the photosensitive pixel 142 through the receiving optical device 144. The field of view partitions 13 corresponding to the multiple photosensitive pixels 142 are spliced together to form the field of view range of the MEMS galvanometer lidar system. Thus, when the beam emitted by the transmitting module 12 scans the field of view partition 13 and there is an object 2 on the field of view partition 13, the beam echo reflected by the object 2 is propagated through the receiving optical device 144 to the corresponding photosensitive pixel 142 for sensing. That is, the optical signal returned from the field of view partition 13 includes photons of ambient light from the field of view partition 13 and also includes the beam echo projected onto the field of view partition 13 and reflected back by the object 2 when there is an object 2 on the field of view partition 13. It should be understood that one field of view partition 13 can be configured to correspond to a single 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 to start working for three-dimensional sensing, and the obtained optical induction signals are combined to obtain the 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 not scanned by the beam can be controlled to stop working to reduce power consumption and reduce the noise caused by ambient light.

[0077] 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 optical signal and convert it into a corresponding electrical signal as the optical induction signal output. Optionally, the photoelectric conversion device may be, for example, a single photon avalanche diode (Single Photon Avalanche Diode, SPAD), an avalanche photodiode (Avalanche Photon Diode, APD), a silicon photomultiplier (Silicon Photomultiplier, SiPM) formed by parallel connection of multiple SPADs, and / or other suitable photoelectric conversion elements, or a combination of the above.

[0078] Figure 3 For Figure 2Schematic three-dimensional optical path diagram of an embodiment of the emission module 12 described in the text. For the convenience of describing the deflection scanning of the light beam emitted by the emission 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 range as the Y-axis, the first direction as the X-axis, and the second direction as the Z-axis. Other optical path schematic diagrams of this application are also described in this coordinate system. It should be understood that in the embodiment where the first direction is the horizontal direction and the second direction is the vertical direction, the XOY plane represents the horizontal plane, and the YOZ plane represents the vertical plane.

[0079] As Figure 3 shown, the emission 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 range. The emission module 12 includes a light source module 122, a MEMS galvanometer module 126, and a deflection angle amplification module 128.

[0080] The light source module 122 is configured to emit a light beam according to a preset timing sequence. The light source module 122 includes one or more light-emitting units (not shown in the figure), and the light-emitting units are configured to emit the light beam. The light-emitting units can be light-emitting devices in the form of vertical cavity surface emitting lasers (Vertical Cavity Surface Emitting Laser, abbreviated as VCSEL, also translatable as vertical resonant cavity surface-emitting laser), edge-emitting lasers (Edge Emitting Laser, EEL), light-emitting diodes (Light Emitting Diode, LED), laser diodes (Laser Diode, LD), fiber lasers, etc. Among them, the edge-emitting laser can be a Fabry Perot (FP) laser, a distributed feedback (Distribute Feedback, DFB) laser, an electro-absorption modulated laser (Electro-absorption Modulated, EML), etc. The embodiments of this application do not make limitations in this regard.

[0081] In some embodiments, the emission module 12 may further include a collimation module 121. The collimation unit 121 is configured to collimate the light beam emitted by the light source module 122 along the optical axis direction to improve the collimation of the light beam emitted by the light source module 122. Optionally, the collimation module 121 may employ collimation optical devices such as collimation lenses, meta-lenses, or cylindrical lenses.

[0082] The MEMS galvanometer module 126 is configured to deflect different reflection angles of the light beam in different time periods in sequence to achieve deflection scanning of the light beam on the field of view range in different time periods. Among them, the reflection angle of the light beam can be defined as the angle by which the light beam deviates from the central direction of the field of view range after reflection, and can also be called the deflection angle of the light beam.

[0083] In some embodiments, the MEMS galvanometer module 126 is configured to deflect the reflection angle of a light beam along different two-dimensional directions, and multiple reflection angles of the light beam can be defined by the angles at which the light beam deviates from the center direction of the field of view range along the first direction and the second direction, respectively. Optionally, the first direction and the second direction can be perpendicularly arranged. For example, in some embodiments, the first direction is the horizontal direction and the second direction is the vertical direction; in some other embodiments, the first direction is the vertical direction and the second direction is the horizontal direction.

[0084] In some other examples, the MEMS galvanometer module 126 is configured to deflect the reflection angle of a light beam along a one-dimensional direction. For example, the MEMS galvanometer module 126 is configured to deflect the reflection angle of a light beam only along the horizontal direction; or, the MEMS galvanometer module 126 is configured to deflect the reflection angle of a light beam only along the vertical direction.

[0085] The deflection angle amplification 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 preset multiple. For example, the deflection angle amplification module 128 amplifies the deflection angles of the light beam along the first direction and / or the second direction by corresponding multiples. Optionally, the deflection angle amplification module 128 includes a lens group having multiple lenses or a metasurface lens, and the deflection angle amplification function of the light beam is realized through the lens group or the metasurface lens.

[0086] The control module 18 includes a transmission control unit 182 and a deflection control unit 184. The deflection control unit 184 is configured to control the MEMS galvanometer module 126 to deflect the reflection angle of the light beam in sequence at different time intervals. The deflection trajectory of the reflection angle can be defined as the reflection path of the light beam by the MEMS galvanometer module 126, which can be understood as the spot change trajectory formed at the corresponding positions within the field of view assuming that there is a light beam reflected when the MEMS galvanometer module 126 is in different reflection angle states, regardless of whether there is actually a light beam reflected.

[0087] 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 different reflection angles corresponding to the MEMS galvanometer module 126, so that the reflected light beam scans at different azimuths 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 to emit the light beam at the corresponding reflection angle of the reflection path to form the 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 exactly the same. The actual scanning path of the light beam is the part of the reflection path of the light beam by the MEMS galvanometer module 126 where the light source module 122 actually emits the light beam. In the embodiments of the present application, the part of the reflection path where the actual scanning path of the light beam is formed is marked with a solid line, and the part of the reflection path that is not the actual scanning path of the light beam is marked with a dashed line.

[0088] For example, in the embodiment as Figure 4 shown, the reflection path 16 of the light beam by the MEMS galvanometer module 126 includes a plurality of first sub-paths 1601, and the first sub-paths 1601 are line segments parallel to the first direction. The plurality of first sub-paths 1601 are arranged parallel to each other and are sequentially spaced 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. During the process of the light beam being reflected by the MEMS galvanometer module 126 and scanning along the first sub-path 1601, it sequentially irradiates a plurality of field of view partitions 13 arranged along the first sub-path 1601. In this case, the first sub-path 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 further includes a plurality of second sub-paths 1602 connecting different first sub-paths 1601. In the embodiment as Figure 4 shown, the second sub-path 1602 is a line segment parallel to the second direction, and the second sub-path 1602 connects the ends of two adjacent first sub-paths 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 on the second sub-path 1602 of the reflection path of the light beam by the MEMS galvanometer module 126, so as to form the actual scanning path of the light beam on the second sub-path 1602. Figure 4The actual scanning path is represented by a solid line. In this case, the light beam scans from one end to the other end along a preset direction on one of the first segments 1601, and can be scanned to an adjacent first segment 1601 through the connected second segment 1602, and the scanning direction is opposite to the scanning direction on the previous first segment 1601. That is, the changing directions of the reflection angles of the light beam on two adjacent first segments 1601 are opposite. The area irradiated by the light beam corresponding to each reflection angle during the scanning process along the first segment 1601 forms a field-of-view partition 13. The two field-of-view partitions 13 scanned by the light beam corresponding to two adjacent reflection angles on the same first segment 1601 can be set to be spliced or partially overlapped with each other, so that all the field-of-view partitions 13 on one first segment 1601 can cover the entire field-of-view angle range corresponding to the first segment 1601 without omission after being superimposed. During the deflection process of the light beam along the second segment 1602, the detection can be switched from the field-of-view partition 13 located at one end of the current first segment 1601 to the field-of-view partition 13 located at the same end of the adjacent first segment 1601. The two field-of-view partitions 13 scanned by the light beam at corresponding positions on two adjacent first segments 1601 can be set to jointly fill the gap between the two adjacent first segments 1601. Thus, after the light beam sequentially scans a plurality of first segments 1601 arranged along the second direction, the entire field-of-view range along the second direction can be covered without omission.

[0089] As Figure 5 shown, in some other embodiments, the reflection path 16 of the MEMS galvanometer module 126 for the light beam includes a plurality of first segments 1601. The first segments 1601 are line segments parallel to the first direction, and the plurality of first segments 1601 are arranged in parallel and at intervals in sequence along the second direction. The reflection path 16 of the MEMS galvanometer module 126 for the light beam further includes a plurality of second segments 1602 connecting different first segments 1601. The second segments 1602 are line segments inclined with respect to the first direction, and respectively connect the ends of two adjacent first segments 1601 located on different sides of each other 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 segment 1602 of the reflection path of the MEMS galvanometer module 126 for the light beam, so as to form an actual scanning path of the light beam on the second segment 1602. Figure 5The actual scanning path is represented by a solid line. In this case, the light beam scans from one end to the other end along a preset direction on one of the first sub-parts 1601, and then scans to the end of the adjacent first sub-part 1601 on the opposite side through the connected second sub-part 1602. The scanning direction on this adjacent first sub-part 1601 is the same as that on the previous first sub-part 1601. That is, the light beam scans along the same scanning direction on different first sub-parts 1601 respectively. Similarly, a field of view partition 13 is formed for the area irradiated by the light beam corresponding to each reflection angle during the scanning process along the first sub-part 1601. The two field of view partitions 13 scanned by the light beam corresponding to two adjacent reflection angles respectively on the same first sub-part 1601 can be set to be spliced or partially overlapped with each other, so that all the field of view partitions 13 on one first sub-part 1601 can cover the entire field of view angle range corresponding to the first sub-part 1601 without omission after being superimposed. During the deflection process of the light beam along the second sub-part 1602, it can be switched from detecting the field of view partition 13 at one end of the current first sub-part 1601 to detecting the field of view partition 13 at the opposite end of the adjacent first sub-part 1601. The field of view partitions 13 scanned at the corresponding positions on two adjacent first sub-parts 1601 can be set to jointly fill the gap between the two adjacent first sub-parts 1601. Thus, after the light beam sequentially scans multiple first sub-parts 1601 arranged along the second direction, it can cover the entire field of view angle range along the second direction of the entire field of view without omission.

[0090] For example, in the embodiment as Figure 6 shown, the reflection path 16 of the light beam by the MEMS galvanometer module 126 is the same as that in the embodiment Figure 4 shown, including a plurality of first sub-parts 1601 parallel to the first direction and a plurality of second sub-parts 1602 parallel to the second direction. The plurality of first sub-parts 1601 are arranged at intervals along the second direction, and the second sub-parts 1602 are respectively connected to the ends of two adjacent first sub-parts 1601 on the same side. Different from the embodiment Figure 4 shown, in the embodiment Figure 6 shown, the emission control unit 182 is configured to control the light source module 122 to emit light when the MEMS galvanometer module 126 deflects and reflects at the corresponding reflection angle along the first sub-part 1601 of the light beam reflection path 16, and stop emitting light when the MEMS galvanometer module 126 deflects and reflects at the corresponding reflection angle along the second sub-part 1602 of the light beam reflection path 16. In this case, the emission module 12 only forms a scanning path on the first sub-part 1601 of the light beam reflection path 16 by the MEMS galvanometer module 126, Figure 6 and the scanning path of this part is represented by a solid line in Figure 6This department's reflection path 16 is represented by a dashed line. Thus, in Figure 6 In the illustrated embodiment, the actual scanning path of the light beam formed by the emission module 12 in the field of view is the first sub - portions 1601 that are parallel to the first direction and arranged at intervals along the second direction in the light beam reflection path 16 of the MEMS galvanometer module 126.

[0091] For example, in the embodiment as Figure 7 shown, the reflection path 16 of the light beam by the MEMS galvanometer module 126 is the same as that in the embodiment as Figure 5 shown, including a plurality of first sub - portions 1601 parallel to the first direction and a plurality of second sub - portions 1602 inclined with respect to the first direction. The plurality of first sub - portions 1601 are arranged at intervals along the second direction, and the second sub - portions 1602 are respectively connected to the ends on different sides of two adjacent first sub - portions 1601 to form a "Z" - shaped reflection path 16. Different from the embodiment as Figure 5 shown, in the embodiment as Figure 7 shown, the emission control unit 182 is configured to control the light source module 122 to emit light when the MEMS galvanometer module 126 deflects and reflects at an angle corresponding to the first sub - portion 1601 of the light beam reflection path 16, and stop emitting light when the MEMS galvanometer module 126 deflects and reflects at an angle corresponding to the second sub - portion 1602 of the light beam reflection path 16. In this case, the emission module 12 only forms a scanning path on the first sub - portion 1601 of the light beam reflection path 16 of the MEMS galvanometer module 126, Figure 6 This part of the scanning path is represented by a solid line, and no actual scanning path of the light beam is formed on the second sub - portion 1602 of the light beam reflection path 16 by the MEMS galvanometer 126, Figure 6 This department's reflection path 16 is represented by a dashed line. Thus, in Figure 6 the illustrated embodiment, the actual scanning path of the light beam formed by the emission module 12 in the field of view is the first sub - portions 1601 that are parallel to the first direction and arranged at intervals along the second direction in the light beam reflection path 16 of the MEMS galvanometer module 126.

[0092] The detection of one frame of the entire field of view by the MEMS galvanometer module lidar system 10 includes a scanning period corresponding to the actual scanning path of the light beam. That is, during the scanning period, in the reflection path 16 of the light beam by the MEMS galvanometer module 126, the light source module 122 also synchronously emits a light beam to form the period of the actual scanning path of the light beam. And the period corresponding to the reflection path 16 of the light beam by the MEMS galvanometer module 126 during which the light source module 122 does not synchronously emit a light beam can be defined as an intermittent period. Since the speed at which the MEMS galvanometer module 126 deflects the reflection angle of the light beam by reflecting along the first branch 1601 is significantly higher than the speed at which it deflects the deflection angle of the light beam along the second branch 1602, it takes a relatively long time for the light beam to deflect from the field-of-view partition 13 at the end of the current first branch 1601 through the MEMS galvanometer module 126 along the second branch 1602 to the field-of-view partition 13 at the start of the next first branch 1601. In Figure 6 and Figure 7 In the embodiments of, the period during which the light beam scans all the field-of-view partitions 13 on one first branch 1601 can be defined as a scanning period. Then, multiple first branches 1601 corresponding to the light beam scanning path form multiple scanning periods, and multiple second branches 1602 in the light beam reflection path 16 of the MEMS galvanometer module 126 during which the light beam is not synchronously emitted form multiple intermittent periods. Corresponding to the connection relationship between the first branch 1601 and the second branch 1602, the intermittent periods connect two adjacent scanning periods. The emission control unit 182 controls the light source module 122 to emit a light beam along the light beam emission path 16 of the MEMS galvanometer module 126 during the scanning period to form the actual scanning path of the light beam, and the emission control unit 182 controls the light source module 122 to stop emitting the light beam during the intermittent period.

[0093] The control module 18 may further include a sensing control unit 186, which is configured to control the corresponding photosensitive pixels 142 to work in sequence and time division according to the scanning orientation of the light beam, so as to receive the optical signal from the field-of-view partition 13 currently scanned by the light beam. The sensing control unit 186 is configured to control the photosensitive pixels 142 to stop working during the intermittent period.

[0094] Among them, multiple field-of-view partitions 13 sequentially distributed along one first branch 1601 are field-of-view partitions 13 in the same row. Multiple photosensitive pixels corresponding to sensing the field-of-view partitions 13 in the same row can be defined as a photosensitive pixel group, and multiple said photosensitive pixel groups respectively correspond to sensing multiple rows of field-of-view partitions 13 arranged in sequence along the second direction. The sensing control unit 186 is configured to control the time-division operation of the photosensitive pixels 142 to be synchronized with the scanning orientation of the light beam, and the sequence of the time-division operation of the photosensitive pixels 142 within the same photosensitive pixel group is the same as the sequence of the corresponding scanning of the field-of-view partitions 13 in the same row along the first branch 1601.

[0095] For example, inFigure 4 and Figure 6 In the embodiment shown, since the light beam scans along opposite scanning directions on two adjacent first sub - sections 1601 respectively, two sensing pixel groups for sensing the field - of - view partitions 13 on two adjacent first sub - sections 1601 are also arranged adjacent to each other correspondingly on the photoelectric sensor 140. The sensing control unit 186 controls the photosensitive pixels 142 inside each of the two adjacent - arranged sensing pixel groups to work in a time - sharing manner in opposite orders.

[0096] For example, in Figure 5 and Figure 7 the embodiment shown, since the light beam scans along the same scanning direction on two adjacent first sub - sections 1601 respectively, two sensing pixel groups for sensing the field - of - view partitions 13 on two adjacent first sub - sections 1601 are also arranged adjacent to each other correspondingly on the photoelectric sensor 140. The sensing control unit 186 is configured to control the photosensitive pixels inside each of the two adjacent - arranged sensing pixel groups to work in a time - sharing manner in the same order.

[0097] The emission control unit 182 is further configured to control the light source module 122 to emit light beam pulses according to a preset time sequence during the corresponding partition detection period for detecting one field - of - view partition 13. The area irradiated by the light beam after being reflected at a preset reflection angle of the MEMS mirror module 126 is the field - of - view partition 13 corresponding to the preset reflection angle.

[0098] In some embodiments, as Figure 8 shown, the first sub - section 1601 includes a middle section and a first section and a second section respectively located on opposite sides of the middle section. The MEMS mirror module 126 deflects the light beam at a higher speed in the middle section than in the first section and the second section. Accordingly, the emission control unit 182 is further configured to correspondingly adjust 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 emission module 12 to the field - of - view partitions 13 in different orientations caused by the change in the speed of the reflection angle of the light beam deflected by the MEMS mirror module 126 along the first sub - section 1601. And the detection effect of the three - dimensional information detection based on the dToF principle, such as detection accuracy, detection precision, and confidence level, etc., is related to the energy of the light beam emitted for detection. Therefore, reducing the difference in the energy of the light beam to the field - of - view partitions 13 in different orientations can narrow the difference in the detection effect on the field - of - view partitions 13 in different orientations. Correspondingly, the sensing control unit 186 is configured to control the working duration of different photosensitive pixels 142 in the same sensing pixel group to first decrease and then increase in sequence according to the order of their respective time - sharing turn - on for work. That is, the sensing control unit 186 controls the working duration of the photosensitive pixels 142 corresponding to sensing the first section and the second section in the same sensing pixel group to be longer than that of the photosensitive pixels 142 corresponding to sensing the middle section.

[0099] 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 the total energy of the light beam emitted by the emission module 12 to different fields of view partitions 13 due to the change in the speed of deflecting the light beam by the MEMS galvanometer module 126 by controlling one or more of the above different parameters.

[0100] It should be understood that the total energy of the light beam emitted by the emission module 12 to the field of view partitions 13 at different azimuths on the first part 1601 is set differently according to different application scenarios. For example, for the vehicle-mounted main lidar, it is required to measure relatively far for the middle field of view partition 13, so the total energy of the light beam emitted by the emission module 12 to the middle field of view partition 13 is relatively high. Therefore, the above-mentioned emission 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 emission module 12 to different fields of view partitions 13 deviating from the original preset value due to the change in the speed of deflecting the light beam by the MEMS galvanometer module 126, rather than meaning that the total energy of the light beam emitted by the emission module 12 to different fields of view partitions 13 is compensated to be the same.

[0101] Specifically, in some embodiments as shown in Figure 8 the emission control unit 182 can be configured to correspondingly control the light source module 122 to emit the light beam at a higher frequency when scanning the middle section than when scanning the first section and the second section. Thus, the difference in the number of light beam pulses emitted to the middle section field of view partition 13 and the first section field of view partition 13 and the second section field of view partition 13 due to the relatively short time for the emission module 12 to emit the light beam to the middle section field of view partition 13 can be compensated. When the emission power of each light beam pulse is the same, the error caused by the relatively short time for emitting the light beam to the middle section field of view partition 13 resulting in the total energy of the emitted light beam deviating from the preset value can be correspondingly compensated, which is beneficial to improving the detection accuracy of the MEMS galvanometer lidar system 10.

[0102] Specifically, in some embodiments as shown in Figure 9In some of the illustrated embodiments, the emission control unit 182 may be configured to correspondingly control the light source module 122 to emit light beams at a higher power when scanning the middle section than when scanning the first and second sections. In the case where the light source module 122 detects different field-of-view partitions 13 at the same light beam emission frequency, since the time for the emission module 12 to emit light beams to the field-of-view partition 13 in the middle section is relatively short, the number of light beam pulses emitted to the field-of-view partition 13 in the middle section during detection will be less than the number of light beam pulses emitted to the field-of-view partitions 13 in the first and second sections. Therefore, setting the power of the light beams emitted by the light source module 122 to the field-of-view partition 13 in the middle section during detection to be higher than the power of the light beams emitted to the field-of-view partitions 13 in the first and second sections can correspondingly compensate for the error caused by the total energy of the light beams emitted to different field-of-view partitions 13 deviating from the preset value due to the above situation, which is beneficial to improving the detection accuracy of the MEMS galvanometer lidar system 10.

[0103] Optionally, in some embodiments, since the light energy loss of the light beam passing through the deflection angle amplification module 128 is proportional to the deflection angle of the light beam after passing through the deflection angle amplification module 128, the deflection angles of the light beams corresponding to scanning the first field-of-view partition 13 and the second field-of-view partition 13 on the first division 1601 after passing through the deflection angle amplification module 128 are larger than the deflection angles of the light beams corresponding to scanning the field-of-view partition 13 in the middle section after passing through the deflection angle amplification module 128. Therefore, the light energy loss generated by the light beams scanning the first field-of-view partition 13 and the second field-of-view partition 13 passing through the deflection angle amplification module 128 will be greater than the light energy loss generated by the light beams corresponding to scanning the field-of-view partition 13 in the middle section passing through the deflection angle amplification 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 to improve the detection accuracy of the MEMS galvanometer lidar system 10, the emission control unit 182 may be configured to correspondingly control the light source module 122 to emit light beams fewer times during the detection of a field-of-view partition 13 in the middle section than during the detection of a field-of-view partition 13 in the first and second sections.

[0104] 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 partition 13 that has been detected on the previous first division 1601 during the intermittent period, so as to obtain corresponding three-dimensional information. Utilizing the intermittent period when detection stops to process the data generated by detecting the field of view partition 13 of the previous first division 1601 can improve the data processing efficiency of the MEMS galvanometer lidar system 10, and at the same time can further reduce the storage medium 30 for caching data, thereby being able to reduce the hardware cost of the MEMS galvanometer lidar system 10.

[0105] In some embodiments, the deflection angle amplification module 128 may 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 in sequence 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 central direction of the field of view range. The foci on one side of the first lens 1281 and the foci on one side of the second lens 1282 coincide with each other within the section between the first lens 1281 and the second lens 1282. That is to say, the light beam reflected and deflected by the MEMS galvanometer module 126 is first converged by the first lens 1281 on the focal plane of the second lens 1282, and then deflected by the second lens 1282 to achieve amplification of the deflection angle.

[0106] For example, in the embodiment as Figure 10 shown, 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 amplification factor M of the deflection angle of the deflection angle amplification module 128 for the light beam is M = F1 / F2. That is to say, the angle by which the light beam deviates from the central direction of the field of view range after being reflected by the MEMS galvanometer module 126 before entering the deflection angle amplification module 128 will be amplified by M times after passing through the deflection angle amplification module 128.

[0107] For example, in the embodiment as Figure 11 shown, the first lens 1281 has positive optical power and the second lens 1282 has negative 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 amplification factor M of the deflection angle of the deflection angle amplification module 128 for the light beam is M = F1 / F2. That is to say, the angle by which the light beam deviates from the central direction of the field of view range after being reflected by the MEMS galvanometer module 126 before entering the deflection angle amplification module 128 will be amplified by M times after passing through the deflection angle amplification module 128.

[0108] 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.

[0109] 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 they are configured to magnify the deflection angles of the passing light beam in all directions by the same multiple. For example, the first lens 1281 and the second lens 1282 magnify the deflection angles 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.

[0110] The number N1 (also referred to as the resolvable number of points) of the deflection angles of the light beam reflected by the MEMS galvanometer module 126 in the first direction is related to the frequency f1 of the deflection angles of the light beam reflected by the MEMS galvanometer module 126 in the first direction, the minimum number of light beam pulses required to be emitted for one reflection angle in the first direction of the MEMS galvanometer lidar system 10 and the time interval ΔT between two consecutive light beam pulses x and is specifically related as the following relationship:

[0111]

[0112] It should be understood that since the number of light beam pulses emitted corresponding to different reflection angles in the first direction of the MEMS galvanometer lidar system 10 may vary, it refers to the minimum value among the number of light beam pulses emitted at each reflection angle deflected in the first direction.

[0113] The number of deflection angles N2 of the light beam reflected by the MEMS galvanometer module 126 in the second direction is related to the frequency f1 of the deflection angles of the light beam reflected by the MEMS galvanometer module 126 in the first direction and the frequency f2 of the deflection angles of the light beam reflected by the MEMS galvanometer module 126 in the second direction, and is specifically as the following relationship:

[0114]

[0115] If the angle range within which the light beam emitted by the MEMS galvanometer lidar system 10 can be deflected in the first direction is θ 1 , and the angle range within which it can be deflected in the second direction is θ 2 , then the angular resolution δθ 1 of the deflection angles of the light beam reflected by the MEMS galvanometer lidar system 10 in the first direction has the following expression:

[0116]

[0117] Wherein, f1 is the frequency of the MEMS galvanometer module 126 deflecting the reflected angle of the light beam in the first direction, is the minimum number of light beam pulses to be emitted for a reflected angle of the MEMS galvanometer lidar system 10 in the first direction and ΔT x is the time interval between two consecutive light beam pulses. is the time required to complete one detection at one of the reflected angles deflected by the MEMS galvanometer lidar system 10 in the first direction. The angular resolution δθ of the MEMS galvanometer lidar system 10 deflecting the reflected angle of the light beam in the second direction 2 The expression is:

[0118]

[0119] Wherein, f1 is the frequency of the MEMS galvanometer module 126 deflecting the reflected angle of the light beam in the first direction, and f2 is the frequency of the MEMS galvanometer module 126 deflecting the reflected angle of the light beam in the second direction.

[0120] It should be understood that the first direction refers to the direction in which the MEMS galvanometer module 126 deflects the reflected 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 part 1601 in the light beam reflection path 16 of the MEMS galvanometer module 126; the second direction refers to the direction in which the MEMS galvanometer module 126 deflects the reflected 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 part 1602 in the light beam reflection path 16. The field-of-view partitions 13 for time-division scanning of the light beam in the field of view are arranged along the first direction. The field-of-view partitions 13 in different rows are arranged along the second direction; alternatively, the second direction connects the field-of-view partitions 13 at the ends of adjacent different rows.

[0121] Optionally, in some embodiments, the first direction is perpendicular to the second direction. For example: the first direction is the horizontal direction and the second direction is the vertical direction; or, the first direction is the vertical direction and the second direction is the horizontal direction.

[0122] When performing beam scanning, the deflection control unit 184 controls the MEMS galvanometer module 126 to sequentially change the different reflection angles of the beam along the reflection path of the 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, so as 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 .

[0123] 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 (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.

[0124] In some embodiments, the processor 40 and / or the storage medium 30 may be disposed in the MEMS galvanometer laser radar system 10, for example, integrated on the same circuit board as the transmitting module 12 or the receiving module 14. Optionally, in some other embodiments, the processor 40 and / or the storage medium 30 may also be disposed at other locations of the electronic device 1, for example, on the main circuit board of the electronic device 1.

[0125] In some embodiments, some or all of the functional units of the control module 18 and / or the processing module 15 can also be implemented by hardware means, for example, by any one of the following techniques or a combination thereof: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), drive circuits for specific objects, and the like.

[0126] It can be understood that different functional units of a part of the control module 18 and / or the processing module 15 can respectively include relevant hardware. For example, the emission control unit 182 can all include the drive circuit of the light source module 122.

[0127] It can be understood that the above-mentioned hardware for implementing the functions of the control module 18 and / or the processing module 15 can be arranged inside the MEMS galvanometer lidar system 10. The above-mentioned hardware for implementing the functions of the control module 18 and / or the processing module 15 can also be arranged at other positions of the electronic device 1, such as on the main circuit board of the electronic device 1.

[0128] As Figure 12 shown, in some embodiments, the MEMS galvanometer lidar system 10 is, for example, a lidar, and the electronic device 1 is, for example, an automobile. The lidar can be installed at multiple different positions on the automobile to detect the distance information of objects within the surrounding range of the automobile and accordingly implement driving control.

[0129] Compared with the lidar that realizes beam scanning by means of mechanical rotation, the lidar provided by the present application uses a semi-solid MEMS galvanometer module 126 to realize the deflection scanning of the beam. Since there is no longer a need to rely on mechanical rotating components, it has higher reliability and a more compact structure, is relatively easy to meet the strict automotive regulations, and has less impact on the appearance of the automobile.

[0130] It should be noted that the technical solution to be protected by the present application can satisfy only one of the above embodiments or simultaneously satisfy multiple of the above embodiments. That is to say, the embodiments combined by one or more of the above embodiments also fall within the protection scope of the present application.

[0131] In the description of this specification, the descriptions referring to terms such as "one embodiment", "certain embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0132] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A MEMS galvanometer laser radar system, characterized in that: The device 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, respectively, and the deflection trajectory of the reflection angle is defined as a reflection path of the light beam by the MEMS galvanometer module, and the reflection path includes a plurality of first subdivisions and a plurality of second subdivisions connecting different first subdivisions, wherein the first subdivisions are line segments parallel to the first direction, and the plurality of first subdivisions are arranged in parallel to each other and are sequentially spaced apart 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; A receiving module is configured to sense an optical signal from the field of view, comprising: A photoelectric sensor, 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 corresponding to the reflection angle where the scanning path is located, and control the corresponding photosensitive pixels to work in sequence and in time-sharing according to the scanning direction of the light beam; Among them, one frame detection of the entire field of view includes multiple scanning periods and an intermittent period connecting two adjacent scanning periods. 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 during the intermittent period to the reflection angle corresponding to the light beam when starting to scan and sense the next first division, and control the light source module to stop emitting the light beam during the intermittent period.

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

3. The MEMS galvanometer laser radar system according to claim 2, characterized in that: The photoelectric conversion device is 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, characterized in that: The first direction and the second direction are arranged 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, characterized in that: The second subsection is a line segment parallel to the second direction, 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 beams on the two adjacent first subsections are opposite; or, The second section is a line segment inclined relative to the first direction, and the second section connects ends of two adjacent first sections on different sides, respectively. 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, characterized in that: The control module is configured to control the processing module to process the light sensing signal data obtained after scanning and sensing the last first sub-section during the intermittent period.

7. The MEMS galvanometer laser radar system according to claim 1, characterized in that: 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 speed higher than that at the first section and the second section.

8. The MEMS galvanometer laser radar system according to claim 7, characterized in that: 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 of the light beam when scanning the first section and the second section when scanning the middle section.

9. The MEMS galvanometer laser radar system according to claim 1, characterized in that: 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 emitted when scanning the middle section.

10. The MEMS galvanometer laser radar system according to claim 1, characterized in that: 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.

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

12. An electronic device, characterized in that: Comprising the MEMS galvanometer laser radar system as described in any one of claims 1-11, the electronic device also includes an application module, and the application module is configured to implement corresponding functions according to the detection results of the MEMS galvanometer laser radar system.

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