All-solid-state laser radar based on digital optical phased array

Abstract

The invention discloses an all-solid-state laser radar based on a digital optical phased array, which comprises a transmitting assembly and a receiving assembly, and is characterized in that the transmitting assembly comprises a transmitting chip and a scanning chip, and the receiving assembly comprises a receiving chip; wherein the scanning chip comprises a digital optical phased array module, and the digital optical phased array module comprises a coupler which is used for coupling a transmitting chip and guiding light emitted by the transmitting chip into the digital optical phased array module; the optical splitter splits the guided light into a plurality of beams of parallel light, and the parallel light enters different optical waveguides for transmission; an optical waveguide that transmits light to the transmission antenna; the optical switches are arranged on the optical waveguides, and light in the corresponding optical waveguides can be smoothly transmitted by controlling the optical switches; and the transmitting antenna is connected with the optical waveguide, and the light transmitted by the optical waveguide is emitted outwards through the transmitting antenna. The laser radar is high in integration level, low in cost, high in stability and large in field angle.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser scanning, and in particular to a full solid-state laser radar based on digital optical phased array. BACKGROUND

[0002] Laser radar (Lidar, light detection and ranging) is a kind of 3D ranging device that measures the distance of objects in the scene by using the time of flight (ToF, Time of Flight) of the light signal from emission, reflection by objects to final reception. Laser radar is mainly applied in the fields of consumer electronics products such as mobile phones, tablets and sweeping robots, as well as the fields of automatic driving, monitoring, unmanned aerial vehicles and other automation.

[0003] The core components of laser radar can be divided into three parts: light source emitting assembly, light source receiving assembly and signal processing hub. The light source emitting assembly of laser radar emits 1D or 2D light pulses to cover a certain field of view in the scene, the receiving chip in the light source receiving assembly receives the pulse echo reflected from the target object, and the signal processing hub records the time of flight of each received light signal to give a histogram and a point cloud diagram, thereby realizing distance detection in 2D dimension. In an ideal state, laser radar needs to cover the distance information in the horizontal and vertical directions of 360-degree full view, so it is generally required that laser radar can emit and receive light in a wide angle.

[0004] Traditional mechanical laser radar generally sets a column of light sources in the vertical direction, and then uses a motor system to drive the column of light sources to rotate horizontally, thereby realizing 360-degree two-dimensional scanning. However, mechanical laser radar often needs multiple discrete devices, resulting in complex optical debugging and assembly, low production efficiency, high cost of components, and thus reducing its competitiveness; the high-frequency rotation of the motor and the complex mechanical structure also cause the mean time to failure to be only 1000-3000 hours, which is difficult to meet the minimum requirement of 13000 hours, i.e. the aging problem of the motor system further reduces the reliability of the mechanical laser radar. In addition, when applied to automatic driving of a car, the mechanical laser radar needs to be arranged at the highest point of the vehicle body to avoid being blocked, but arranging the mechanical laser radar and the reinforcing structure on the roof of the vehicle can easily affect the vehicle's center of gravity, affect driving safety, the protruding laser radar is also more likely to be damaged, and the laser radar arranged on the roof also greatly affects the vehicle styling.

[0005] To overcome the problems of mechanical LiDAR, hybrid solid-state LiDAR has been proposed in recent years, employing methods such as rotating mirror scanning, prism scanning, or galvanometer scanning based on microelectromechanical systems (MEMS). The most representative of these is the MEMS-based galvanometer scanning scheme. A MEMS galvanometer is a miniature integrated system that utilizes microfabrication technology to mass-produce channels, holes, cantilever arms, films, cavities, and other micromechanical structures on a chip, and then integrates them with corresponding circuits using integrated circuit manufacturing technology. Light deflection on the miniature structure is achieved by controlling the rotation of the rotating arm. Compared to mechanical LiDAR, hybrid solid-state MEMS LiDAR significantly reduces cost and size. However, to achieve sufficient light deflection angle and accuracy, the weight of the mirror on the MEMS system has a significant impact on the galvanometer cantilever arm, thus affecting the system's reliability and severely limiting its application scenarios.

[0006] On the other hand, the rotating mirror scanning scheme is a high-speed polygon scanner, consisting of a motor and a polyhedron with multiple mirrors, also known as a multi-faceted laser motor. By rotating the motor, the multi-faceted mirrors can rotate at high speed, thus achieving beam scanning. It has wide applications in optical imaging, thin film inspection, materials processing, laser printing plate making, and printed circuit board inspection. The rotating mirror features a large scanning angle, high scanning frequency, and large effective optical aperture, meeting the performance requirements of lidar for a large field of view and high frame rate, and is therefore used in lidar. However, the rotating mirror is often quite large, making further miniaturization and cost reduction difficult.

[0007] In summary, both the rotating mirror solution and the MEMS solution have questionable reliability, stability, and integration due to the presence of internal micro-mechanical structures. Summary of the Invention

[0008] To address one of the technical problems existing in the prior art, this application provides an all-solid-state lidar based on a digital optical phased array, which utilizes the digital optical phased array to achieve a large field of view.

[0009] According to the first aspect of the present application, a full solid-state laser radar based on digital optical phased array includes a transmitting assembly and a receiving assembly, the transmitting assembly includes a transmitting chip and a scanning chip, and the receiving assembly includes a receiving chip; wherein the scanning chip includes a digital optical phased array module, the digital optical phased array module includes: a coupler, used for coupling the transmitting chip and guiding the light emitted by the transmitting chip into the digital optical phased array module; a beam splitter, which divides the guided light into multiple parallel beams and respectively enters different optical waveguides for transmission; an optical waveguide, which transmits light to a transmitting antenna; an optical switch, which is arranged on each optical waveguide and controls the smooth transmission of light in the corresponding optical waveguide; and a transmitting antenna, which is connected to the optical waveguide, and the light transmitted by the optical waveguide is emitted outward through the transmitting antenna.

[0010] According to the first aspect of the present application, the full solid-state laser radar based on digital optical phased array, the digital optical phased array module includes a first lens group, and the light emitted from the transmitting antenna is deflected and radiated after passing through the first lens group.

[0011] According to the first aspect of the present application, the full solid-state laser radar based on digital optical phased array, the first lens group is an independent lens arranged outside the scanning chip.

[0012] According to the first aspect of the present application, the full solid-state laser radar based on digital optical phased array, the first lens group is an integrated super surface lens on the transmitting antenna.

[0013] According to the first aspect of the present application, the full solid-state laser radar based on digital optical phased array, the transmitting assembly includes a transmitting drive and a scanning drive, the transmitting drive is connected to the transmitting chip, and the scanning drive is connected to the scanning chip.

[0014] According to the first aspect of the present application, the full solid-state laser radar based on digital optical phased array, the laser radar further includes a control chip, and the control chip is connected to the transmitting drive, the scanning drive and the receiving chip respectively.

[0015] According to the first aspect of the present application, the full solid-state laser radar based on digital optical phased array, the receiving chip includes a SPAD chip or an APD chip.

[0016] According to the first aspect of the present application, the full solid-state laser radar based on digital optical phased array, the transmitting chip includes an EEL chip or a VCSEL chip.

[0017] According to the first aspect of the present application, the full solid-state laser radar based on digital optical phased array, two or more scanning chips are arranged in the transmitting assembly.

[0018] According to the all-solid-state lidar based on digital optical phased array provided in the first aspect of this application, the transmitting component includes an optical diffuser.

[0019] According to the all-solid-state lidar based on digital optical phased array provided in the first aspect of this application, the receiving component includes a lens group.

[0020] This application has the following beneficial effects:

[0021] The all-solid-state lidar based on digital optical phased array of this application uses optical phased array technology to deflect light, thereby eliminating all mechanical devices and other large modules. It adopts fewer chips to make the system architecture more compact, reduce size and cost, and improve reliability, thus realizing a lidar with high integration, low cost, high stability and large field of view.

[0022] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the description, claims and drawings. Attached Figure Description

[0023] To more clearly illustrate the technical solution of this application, the following description will be provided in conjunction with the accompanying drawings and embodiments. It should be understood that the following drawings only show some embodiments of this application and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort. In the drawings:

[0024] Figure 1 This is a block diagram of the all-solid-state lidar provided in this application;

[0025] Figure 2 This is a block diagram of the digital optical phased array provided in this application;

[0026] Figure 3 This is a top view of the transmitting antenna and the independent lens;

[0027] Figure 4 yes Figure 3 Side view of the transmitting antenna and independent lens;

[0028] Figure 5 This is a schematic diagram of a metasurface lens integrated on a transmitting antenna;

[0029] Figure 6 This is a schematic diagram of 1D scanning using a long strip of light.

[0030] Figure 7 is a schematic diagram of 2D scanning using a single spot;

[0031] Figure 8 is a schematic diagram of 2D scanning using a long strip spot.

[0032] BRIEF DESCRIPTION OF DRAWINGS

[0033] Transmitting assembly 100, transmitting chip 110, scanning chip 120, coupler 121, beam splitter 122, optical waveguide 123, optical switch 124, transmitting antenna 125, first lens group 126, independent lens 127, nanobrick 128, transmitting driver 130, scanning driver 140, receiving assembly 200, receiving chip 210, control chip 300, single spot 410, long strip spot 420. DETAILED DESCRIPTION

[0034] The application will be further described below in conjunction with the drawings. Similar elements in different embodiments are denoted by similar reference numbers. In the following embodiments, many details are described to make the application better understood. However, one skilled in the art can easily recognize that some features can be omitted in different cases, or replaced by other elements, materials, methods. In some cases, some operations related to the application are not shown or described in the specification, in order to avoid the core part of the application being overwhelmed by too much description, and it is not necessary to describe these related operations in detail for one skilled in the art, who can fully understand the related operations according to the description in the specification and general technical knowledge in the art.

[0035] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate way to form various embodiments. At the same time, the steps or actions in the method description can also be sequentially adjusted or adjusted in a manner that one skilled in the art can easily see. Therefore, the order in the specification and drawings is only for the purpose of clearly describing a certain embodiment, and does not mean that it is the necessary order, unless otherwise stated that a certain order must be followed.

[0036] The serial numbers of components in this paper, such as "first", "second", etc., are only used to distinguish the described objects, and have no order or technical meaning. Unless otherwise specified, "connection" and "coupling" in this application include direct and indirect connection (coupling).

[0037] The following will be described in conjunction with the drawings Figure 1 to the drawings Figure 8 The embodiments provided in this paper further illustrate the all-solid-state laser radar based on digital optical phased array proposed in this application.

[0038] Reference is made to Figure 1In the embodiments of the present application, a full solid-state laser radar based on a digital optical phased array is provided, which includes a transmitting assembly 100 and a receiving assembly 200. The light signal emitted by the transmitting assembly 100 is reflected back by an object and received by the receiving assembly 200, and the time of flight (ToF) of the light signal is calculated to measure the distance of the object in the scene. The transmitting assembly 100 includes a transmitting chip 110 and a scanning chip 120, a transmitting driver 130 for driving the transmitting chip 110 to work, and a scanning driver 140 for driving the scanning chip 120 to work. The transmitting driver 130 is connected to the transmitting chip 110, and the scanning driver 140 is connected to the scanning chip 120. The transmitting chip 110 generally adopts a semiconductor laser technology chip, such as an edge-emitting laser (EEL) or a single-mode vertical-cavity surface-emitting laser (VCSEL). The present application takes a single-mode vertical-cavity surface-emitting laser as an example to illustrate the system scheme, but is not limited to this type of chip. The scanning chip 120 generally adopts an integrated optical platform-based optical device, such as a silicon photonics device based on a silicon / nitride silicon (Si / SiN) platform or a photonic device based on a lithium niobate thin film (LNOI) platform. Since the lithium niobate thin film has good electro-optic effect, the effect is efficient and reliable. The present application takes an optical phased array (OPA) based on a lithium niobate thin film as an example to illustrate the system scheme, but is not limited to this type of chip. The transmitting driver 130 and the scanning driver 140 are respectively developed in correspondence with the characteristics of the transmitting chip 110 and the scanning chip 120, so as to effectively control the transmitting chip 110 and the scanning chip 120. The receiving assembly 200 includes a receiving chip 210. In some embodiments, the receiving chip 210 can be a chip developed based on an avalanche photodiode (APD). In other embodiments, the receiving chip 210 can also be a chip developed based on a single photon avalanche diode (SPAD). Since the SPAD chip can adopt a 3D stacking technology under a CMOS (Complementary Metal Oxide Semiconductor) process, a special integrated circuit (ASIC) can form a highly customized integrated chip. Compared with the APD chip, the performance-price ratio of the SPAD chip is further improved. Therefore, the present patent takes a SPAD chip that perceives near-infrared (NIR) waves as an example to illustrate the system scheme, but is not limited to this type of chip.In addition, the laser radar further comprises a control chip 300 connected with the emission driver 130, the scanning driver 140 and the receiving chip 210 respectively, and the control chip 300 is used to exchange state information among the emission driver 130, the scanning driver 140 and the receiving chip 210, so that the laser radar works in a correct state. Meanwhile, when the emission chip 110 emits the light signal, a synchronization signal is sent to the receiving chip 210, so that the ranging accuracy is relatively high; the synchronization signal can be a signal of the emission assembly 100 or a synchronization signal formed by a photoelectric detector reserved in the receiving chip 210.

[0039] As shown in Figure 2 In some embodiments of the present application, the scanning chip 120 comprises a digital optical phased array module (digital OPA), which comprises a coupler 121, a beam splitter 122, an optical waveguide 123, an optical switch 124 and a transmission antenna 125. The coupler 121 is used to couple the emission chip 110 and guide the light emitted by the emission chip 110 into the digital optical phased array module; the beam splitter 122 divides the guided light into multiple parallel beams which enter different optical waveguides 123 for transmission; the optical switch 124 is arranged on the optical waveguide 123, and by controlling the optical switch 124, the light in the corresponding optical waveguide 123 can be smoothly transmitted; the transmission antenna 125 is connected with the optical waveguide 123, and the light signal is radiated outward after being transmitted to the transmission antenna 125. It should be pointed out that the light emitted outward from the transmission antenna 125 is discontinuous based on the digital optical phased array module, and therefore other optical components are needed to deflect the output light, and the design generally adopts a first lens group 126 to deflect the output light, so as to realize continuous scanning with a large field of view (FoV, Field of View). Figures 2 to 5

[0040] Further, the first lens group 126 has at least two setting modes.

[0041] As shown in Figure 3 and Figure 4 In some embodiments, the first lens group 126 can be an independent lens 127 arranged outside the emission chip 110, and the transmission antenna 125 is located at the focal plane of the independent lens 127, as shown in Figure 4 ​As shown, the light emitted by the transmitting antenna 125 is deflected by the independent lens 127 before being emitted, thereby achieving continuous scanning with a large field of view. The scanning field of view depends on the focal length and longest dimension of the transmitting antenna 125, while the scanning accuracy depends on the focal length and spacing of the transmitting antennas 125. Furthermore, it is readily understood that this application does not limit the number of independent lenses 127. In other embodiments, developers can, according to actual needs, place multiple independent lenses 127 outside the transmitting chip 110 to form the first lens group 126. The advantages of using independent lenses 127 in the first lens group 126 include: reduced manufacturing difficulty of components; and ease of replacement since the independent lenses 127 are located outside the transmitting chip 110, allowing the lidar to adapt to more scenario requirements. The disadvantages of using independent lenses 127 in the first lens group 126 are a larger number of components and increased assembly steps.

[0042] like Figure 5 As shown, in some embodiments, the first lens group 126 can also be a metasurface lens integrated on the transmitting chip 110. The metasurface lens is composed of several nanobricks 128, with one nanobrick 128 correspondingly disposed above each transmitting antenna 125. The pre-designed shape, angle, and size of the nanobricks 128 can be used to deflect light, and the deflection phase of each nanobrick 128 can be set independently. Light enters different transmitting antennas 125 through the optical waveguide 123. The phase of light changes when passing through the pre-processed nanobricks 128 in different transmitting antennas 125, thereby achieving fixed light deflection within a preset range. It should be noted that common materials for nanobricks 128 include silicon (Si), silicon nitride (Si3N4), amorphous silicon (α-Si), titanium dioxide (TiO2), gallium arsenide (GaAs), germanium (Ge), and metal-dielectric hybrids (such as Au / SiO2 core-shell). The advantages of integrating the first lens group 126 onto the transmitter chip 110 include: reducing the number of components and further reducing the size of the lidar, while also reducing assembly steps; the disadvantage of integrating the first lens group 126 onto the transmitter chip 110 is that the process requirements are relatively high.

[0043] The all-solid-state lidar based on digital optical phased array of this application uses optical phased array technology to deflect light, thereby eliminating all mechanical devices and other large modules. It adopts fewer chips to make the system architecture more compact, reduce size and cost, and improve reliability, thus realizing a lidar with high integration, low cost, high stability and large field of view.

[0044] Furthermore, the emitting chip 110 employs either a side-emitting laser or a single-mode vertical-cavity surface-emitting laser, both of which facilitate miniaturization. However, both also face heat dissipation problems due to low electro-optical efficiency. Therefore, maintaining good heat dissipation while emitting high power is a critical issue. Taking ToF technology based on SPAD chips as an example, multiple emissions are required to improve the signal-to-noise ratio. Therefore, when the detection distance is long, the emission power needs to be high, and the number of emissions also increases significantly. Therefore, this application proposes an all-solid-state lidar based on a digital optical phased array. The signal light emitted by the emitting chip 110 is guided into the scanning chip 120 via optical fiber. Then, the coupler 121, beam splitter 122, and optical waveguide 123 at the coupling port complete the transmission of the corresponding optical channels, thereby forming effective optical manipulation. This can significantly reduce the number of light sources to 2-3 groups, thereby significantly reducing the use of the emitting chip 110, reducing heat generation, and incidentally reducing procurement costs. In addition, during scanning, different groups of light sources can be used alternately, and the duty cycle of the light source emission can be significantly reduced, thereby improving its heat dissipation capacity.

[0045] The transmitting antenna 125 can perform both 1D and 2D scanning. The following example illustrates the 1D scanning method. For example... Figure 6 As shown, taking lateral scanning as an example, firstly, the light signal emitted by the transmitting component 100 forms a long strip of light spot 420 in the scanning area. Then, the control chip 300 controls the scanning drive 140 to output a drive current / voltage, and the scanning chip 120 deflects the light, thereby causing the long strip of light spot 420 to move along... Figure 6 Moving in the direction indicated by the arrow achieves horizontal scanning. Specifically, taking the field of view of an area array lidar as an example, it is generally FoV-H = 120°, FoV-V = 70°. Assuming the receiving resolution is RH = 0.2°, the emitted light spot can be a long strip of light spot 420 of 0.2° * 70°, covering a single pixel in the horizontal direction, or it can be a long strip of light spot of 1° * 70° covering 5 pixels in the horizontal direction, depending on the system configuration at the receiving chip. It should be noted that there are no restrictions on the number of light spots or the scanning direction (horizontal or vertical). Those skilled in the art can set two or more light spots according to the actual situation, or choose a vertical scanning method. In addition, the light spot emitted by the digital optical phased array module is generally a single-point light spot. Therefore, an optical diffuser is also provided in the transmitting component 100 to stretch the light spot in the vertical / horizontal direction, thereby obtaining the long strip of light spot 420. In some embodiments, the optical diffuser can be a cylindrical lens or a diffractive optical element (DOE).

[0046] Furthermore, since the digital optical phased array module uses electro-optic control, its deflection speed can reach the microsecond level, thus allowing for two-dimensional scanning. For example... Figure 7 As shown, in some embodiments, a single-point light spot 410 is used for two-dimensional scanning. First, the light signal emitted by the transmitting component 100 forms a single-point light spot 410 in the scanning area. Then, the control chip 300 controls the scanning drive 140 to output a drive current / voltage, and the scanning chip 120 deflects the light, thereby causing the single-point light spot 410 to move along... Figure 7 The direction indicated by the arrow is first used for horizontal scanning, followed by vertical displacement. After displacement, another horizontal scan is performed, repeating this process multiple times until the entire scanning area is scanned, thus achieving 2D scanning. Using a single-point spot 410 for 2D scanning reduces the requirements for optical components because an optical diffuser is not needed, but it places higher demands on the system's frame rate and scanning speed. Furthermore, as... Figure 8 As shown, an optical diffuser can also be combined with 2D scanning to stretch a single-point light spot into a smaller, elongated light spot 420, such as... Figure 8 If FoV-V = 70°, then the vertical field of view RV covered by the long strip of light spot 420 can be 35° or 17.5°, etc. By using a sparse 2D array and a small-scale diffusion of the optical diffuser, the requirements for the optical diffusion device can be reduced while ensuring a large-scale FoV scan and a high-quality light spot. At the same time, the number of reciprocating scans can be reduced to ensure that the scanning speed meets the requirements.

[0047] It is easy to understand that in practical applications, the scanning path of the light spot is not necessarily as shown in the above figure. Under the condition of meeting the frame rate, the digital optical phased array module can support arbitrary selection of scanning path according to the scene and system requirements, and also support pixel skipping scanning operation, which is not specifically illustrated in this application.

[0048] Furthermore, in some embodiments of this application, the lidar can support simultaneous scanning and reception using two or more light spots, which reduces the requirements for scanning speed. Meanwhile, because it is difficult to achieve a large field of view and low resolution with the scanning chip 120, and this can lead to a series of problems such as channel crosstalk and low sidelobe suppression ratio, thus affecting the signal-to-noise ratio, in order to solve these problems, in some embodiments of this application, two or more scanning chips 120 can be set within the transmitting component 100. By stitching together two or more scanning chips 120, it is easier to obtain a large field of view. Taking a 120° lateral field of view as an example, one scanning chip 120 covers a 60° field of view, and two chips can meet the product's requirements. Compared to a 120° field of view scanning chip 120, two 60° field-of-view scanning chips 120 significantly reduce the technical challenges in design and manufacturing.

[0049] Further, in some embodiments of the present application, a SPAD chip is used as the receiving chip 210. The SPAD chip uses a digital design and can receive multiple pixels simultaneously. By selecting the corresponding pixels, the TDC (Time-to-digital Converter) module can record the time stamp of the corresponding pixel signal. Generally, the SPAD chip usually uses the TCSPC (Time-Correlated Single Photon Counting) or Coincidence Measurement working principle to calculate the distance of the object by ToF. Through multiple laser signal transmissions, the SPAD chip can detect the time of the returned photons, thereby forming a histogram. In order to further improve the signal-to-noise ratio, the common solutions are to reduce the ambient light level, improve the performance of the SPAD chip, and increase the transmission power and transmission times, so that the signal-to-noise ratio can meet the signal processing requirements. Based on this technical principle, the SPAD chip can control the corresponding pixel to read the time-of-flight data according to different transmission and scanning spot modes, and use the histogram to form an effective point cloud map. The SPAD chip can simultaneously receive multiple columns of adjacent or non-adjacent pixels, thereby receiving the optical signals collected by the multiple columns of pixels. The SPAD chip controls any one photosensitive pixel to match into the corresponding TDC to realize the above operation. One TDC can control whether the signal of any one pixel is accessed into the TDC through the data selector Mux. When accessed into the TDC, the signal serves as the stop signal of the TDC to inform the chip that a flying photon is detected at the time point. For example, when the transmission assembly 100 emits a long strip spot of 0.4°*70°, the receiving side can use 2 columns of pixels to make the transmission and reception one-to-one corresponding, thereby forming a picture resolution of 0.2°. When the transmission assembly 100 emits a long strip spot of 0.4°*70°, the receiving side can also use 4 columns of pixels to make the transmission and reception one-to-one corresponding, thereby forming an effective picture resolution of 0.1°. By using the digital scheme, a more flexible system configuration and measurement scheme can be realized. Under this architecture, the signal-to-noise ratio can be improved by transmitting a small amount of power and counting multiple times. Due to the high sensitivity of the SPAD chip, the requirement for the light source is lower than that of the traditional APD and PIN.

[0050] In addition, the SPAD chip also has process advantages. Generally speaking, taking 40 nm process as an example, the number of TDCs that can be accommodated by one SPAD chip is 8*180, which can support up to 8 columns of pixels to receive signals at the same time. Since the SPAD chip is of digital architecture, if 22 / 28 nm process is adopted, the chip area can be smaller, and under the premise of the same size, the number of TDCs that can be supported can be further improved. This is also the advantage of the digital SPAD chip, which follows Moore's Law, and can improve chip performance and reduce cost by improving process nodes.

[0051] Further, in order to improve the accuracy of the receiving chip 210, a second lens group is also arranged in the receiving assembly 200, which focuses the reflected light spot and allows the receiving chip 210 to receive, thereby improving the accuracy of the receiving chip 210.

[0052] It can be understood that the above embodiments only express the preferred embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent of the present application; it should be pointed out that for ordinary skilled in the art, the above technical features can be freely combined without departing from the concept of the present application, and some modifications and improvements can be made, which belong to the protection scope of the present application; therefore, any equivalent transformation and modification within the scope of the claims of the present application shall belong to the scope of the claims of the present application.

Claims

1. A digital optical phased array based all solid state lidar, characterized by, The laser radar comprises a transmitting assembly and a receiving assembly, the transmitting assembly comprises a transmitting chip and a scanning chip, and the receiving assembly comprises a receiving chip; The scanning chip comprises a digital optical phased array module, and the digital optical phased array module comprises: A coupler is arranged to couple the transmitting chip and guide light emitted by the transmitting chip into the digital optical phased array module; A beam splitter is arranged to split the guided light into multiple beams of parallel light to be respectively input into different optical waveguides for transmission; An optical waveguide is arranged to transmit light to a transmitting antenna; An optical switch is arranged on each optical waveguide, and the light in the corresponding optical waveguide can be smoothly transmitted by controlling the optical switch; The transmitting antenna is connected to the optical waveguide, and the light transmitted by the optical waveguide is emitted outward through the transmitting antenna.

2. The digital optical phased array based all solid state lidar of claim 1, wherein, The digital optical phased array module comprises a first lens group, and the light emitted from the transmitting antenna is deflected and radiated after passing through the first lens group.

3. The digital optical phased array based all solid state lidar of claim 2, wherein, The first lens group is an independent lens arranged outside the scanning chip.

4. The digital optical phased array based all solid state lidar of claim 2, wherein, The first lens group is a metasurface lens integrated on the transmitting antenna.

5. The digital optical phased array based all solid state lidar of claim 1, wherein, The transmitting assembly comprises a transmitting drive and a scanning drive, the transmitting drive is connected to the transmitting chip, and the scanning drive is connected to the scanning chip.

6. The digital optical phased array based all solid state lidar of claim 5, wherein, The laser radar further comprises a control chip, and the control chip is connected to the transmitting drive, the scanning drive and the receiving chip.

7. The digital optical phased array based all solid state lidar of claim 1, wherein, The receiving chip comprises an SPAD chip or an APD chip.

8. The digital optical phased array based all solid state lidar of claim 1, wherein, The transmitting chip comprises an EEL chip or a VCSEL chip.

9. The digital optical phased array based all solid state lidar of claim 1, wherein, Two or more scanning chips are arranged in the transmitting assembly.

10. The digital optical phased array based all solid state lidar of claim 1, wherein, The transmitting assembly comprises an optical diffuser.

Images