Lidar and movable device

Abstract

This application discloses a lidar and a mobile device. The lidar includes a first optical transceiver module, a second optical transceiver module, and a wavelength division multiplexing (WDM) element. The first optical transceiver module includes a first laser and a first detector, with the first laser generating a first detection light. The second optical transceiver module includes a second laser and a second detector, with the second laser generating a second detection light. One of the first and second detection lights is a pulsed wave signal, and the other is a continuous wave signal. The second and first detection lights are used to detect target objects and have different wavelengths. The WDM element is located upstream of the first and second detectors, along the transmission direction of the first and second echo lights. The WDM element receives the first and second echo lights and divides them to output the first and second echo lights. This application's technical solution improves upon the current limitations of ToF lidar in terms of acquisition speed and timeliness.

Description

Technical Field

[0001] This application relates to the field of electronic device technology, and in particular to a lidar and a mobile device using the lidar. Background Technology

[0002] In fields such as intelligent transportation and autonomous driving, rapid and accurate perception of the surrounding environment of roads and autonomous vehicles is crucial. By coordinating road signal control based on information about road, vehicle positions, and obstacles obtained from sensor devices, the quality and efficiency of road management can be improved.

[0003] Most current lidar technologies are Time-of-Flight (ToF) lidar, which measures distance by transmitting pulse signals and analyzing the time interval between the transmission and reception of these pulses. However, ToF lidar is only suitable for direct distance measurement. If speed needs to be measured, the speed between adjacent frames must be calculated based on the distance measurement results from multiple frames. This method of acquiring speed is time-consuming, typically exceeding 300ms, which is insufficient for the timeliness requirements of autonomous driving perception. Summary of the Invention

[0004] This application provides a lidar and a mobile device to improve the current situation where the acquisition speed of ToF lidar is insufficient in terms of timeliness.

[0005] In a first aspect, embodiments of this application provide a lidar, which includes:

[0006] The first optical transceiver module includes a first laser and a first detector, wherein the first laser is used to generate a first probe light;

[0007] The second optical transceiver module includes a second laser and a second detector. The second laser is used to generate a second detection light. One of the first and second detection lights is a pulsed wave signal, and the other is a continuous wave signal. The second detection light and the first detection light are used to detect target objects and have different wavelengths.

[0008] A wavelength division element is located upstream of the first detector and the second detector along the transmission direction of the first echo and the second echo. The wavelength division element is used to receive the first echo and the second echo and divide them to output the first echo and the second echo. The first echo is formed by the reflection of the first detection light by the target object, and the second echo is formed by the reflection of the second detection light by the target object.

[0009] The first detector is used to receive the first echo light, and the second detector is used to receive the second echo light.

[0010] In some embodiments, the continuous wave is a constant frequency continuous wave.

[0011] In some embodiments, the wavelength division element is a dichroic mirror.

[0012] In some embodiments, the wavelength division element is further configured to receive the first probe light and the second probe light, combine them, and output the combined first probe light and the second probe light.

[0013] In some embodiments, the lidar further includes a first reflector;

[0014] Along the transmission direction of the first probe light, the first reflector is located between the first laser and the wavelength division element, and the first reflector is used to reflect the first probe light to the wavelength division element.

[0015] In some embodiments, the lidar further includes a first lens module;

[0016] Along the transmission direction of the first probe light, the first lens module is located upstream of the wavelength division element. The first lens module includes at least one lens and is used to collimate the first probe light.

[0017] In some embodiments, the lidar also includes a second lens module;

[0018] Along the transmission direction of the first echo light, the second lens module is located between the wavelength division element and the first detector. The second lens module includes at least one lens and is used to receive the first echo light and focus the first echo light.

[0019] Along the first direction, the second lens module is disposed on the side of the first reflector away from the wavelength division element, and the first direction is the opposite direction of the first reflector reflecting the first probe light.

[0020] In some embodiments, the lidar also includes a third lens module;

[0021] Along the transmission direction of the second probe light, the third lens module is located upstream of the wavelength division element. The third lens module includes at least one lens and is used to collimate the second probe light.

[0022] In some embodiments, the lidar also includes a multiplexing element;

[0023] The beam combiner is used to receive the first detection light and the second detection light, and combine them into a single beam of light to detect the target object.

[0024] In some embodiments, the lidar also includes a second reflector;

[0025] Along the transmission direction of the first probe light, the second reflector is located downstream of the combining element, and the reflector is used to reflect the combined first probe light and the second probe light.

[0026] In some embodiments, the lidar also includes a fourth lens module;

[0027] Along the transmission direction of the first probe light, the fourth lens module is located downstream of the multiplexing element. The fourth lens module includes at least one lens and is used to collimate the first probe light and the second probe light after multiplexing.

[0028] In some embodiments, the lidar also includes a fifth lens module;

[0029] Along the transmission direction of the first echo light, the five-lens module is located upstream of the wave splitter element. The fifth lens module includes at least one lens and is used to receive the first echo light and the second echo light, and to focus the first echo light and the second echo light.

[0030] In some embodiments, along a first direction, the fifth lens module is disposed between the second reflector and the wave splitter element, and the first direction is the opposite direction of the second reflector reflecting the first probe light and the second probe light;

[0031] When viewed along the first direction, the cross-sectional profile of the fifth lens module covers the second reflector.

[0032] In some embodiments, the lidar also includes a beam splitter;

[0033] Along the transmission direction of the first probe light, the beam splitter is located downstream of the wave combiner; along the transmission direction of the first echo light, the beam splitter is located upstream of the wave combiner.

[0034] The beam splitter includes a reflective region and a transmission region. The reflective region is used to reflect the first and second probe beams after beam combining, and the transmission region is used to transmit the first and second echo beams.

[0035] The transmission zone is arranged around the reflection zone.

[0036] Secondly, the mobile device provided in this application includes a movable main body and a lidar as described above.

[0037] This application embodiment incorporates two optical transceiver modules within a lidar system. A first optical transceiver module generates a first probe light, and a second optical transceiver module generates a second probe light. The first and second probe lights are emitted as a single beam outside the lidar system. One of the beams is a pulse wave signal, and the other is a continuous wave signal; their wavelengths are different. A wavelength division element receives the first and second echo lights and splits them into a first echo light propagating towards a first detector and a second echo light propagating towards a second detector. Thus, this lidar system can perform distance detection using the pulse wave signal and velocity detection using the continuous wave signal. Compared to ToF lidar, this lidar system can detect both distance and velocity within a single frame of data, resulting in higher timeliness. Furthermore, compared to traditional FMCW lidar systems that use frequency-modulated continuous waves for detection, which require high-frequency beat signals and high-speed analog-to-digital converters for sampling, this lidar system can achieve sampling using an analog-to-digital converter with a lower sampling rate, thereby reducing overall device costs. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0039] Figure 1 This application provides a schematic diagram of the optical path of a lidar according to the first embodiment of the present application.

[0040] Figure 2 This is a schematic diagram of the optical path of the lidar according to the second embodiment of this application;

[0041] Figure 3 This application provides a schematic diagram of the optical path of a lidar according to a third embodiment.

[0042] Figure 4 A schematic diagram of the structure of an embodiment of the mobile device provided in this application.

[0043] Explanation of icon numbers:

[0044] 100. LiDAR; 110. First optical transceiver module; 111. First laser; 112. First detector; 120. Second optical transceiver module; 121. Second laser; 122. Second detector; 130. Wavelength division element; 131. First surface; 132. Second surface; 140. Wavelength multiplexing element; 151. First reflector; 152. Second reflector; 161. First lens module; 162. Second lens module; 163. Third lens module; 164. Fourth lens module; 165. Fifth lens module; 170. Beam splitter; 171. Reflection area; 172. Transmission area; 200. Movable main body; 300. Movable device.

[0045] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0047] Where the following description relates to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0048] In the description of this application, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, in the description of this application, unless otherwise stated, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0050] Please see Figure 1This application proposes a lidar 100. In this embodiment, the lidar 100 includes a first optical transceiver module 110, a second optical transceiver module 120, and a wavelength division multiplexing element 130. The first optical transceiver module 110 includes a first laser 111 and a first detector 112. The first laser 111 generates a first detection light. The second optical transceiver module 120 includes a second laser 121 and a second detector 122. The second laser 121 generates a second detection light. One of the first and second detection lights is a pulse wave signal, and the other is a continuous wave signal. The second and first detection lights are used to detect target objects and have different wavelengths. The first detector 112 receives a first echo light formed by the reflection of the first detection light from the target object, and the second detector 122 receives a second echo light formed by the reflection of the second detection light from the target object.

[0051] In this embodiment, the first laser 111 and the second laser 121 can be lasers from related technologies. The mechanism of the pulse wave signal in the first and second probe lights can refer to the form of TOF lidar, while the mechanism of generating the continuous wave signal can refer to the form of FMCW or CW lidar. For example, in some embodiments, the first laser 111 uses a commonly used edge-emitting laser to generate a pulse wave signal with a wavelength of 905nm. The second laser 121 uses a distributed feedback laser to generate a continuous wave signal with a wavelength of 1550nm. It is understood that the wavelengths of the first and second probe lights can be adaptively adjusted; the wavelength of the first probe light can be greater than or less than the wavelength of the second probe light. This application does not specifically limit the size between the two, as long as the wavelengths are different to facilitate wave division when receiving the first and second echo lights. Alternatively, the first probe light can be a continuous wave signal, and the second probe light can be a pulse wave signal. That is, the configuration of the first optical transceiver module 110 and the second optical transceiver module 120 can be interchanged, and this application does not limit this. The following content will still take the example of the first probe light being a pulse wave signal and the second probe light being a continuous wave signal to elaborate on the content of this application.

[0052] After the first and second probe beams are emitted, they are directed towards the target object. The first probe beam is reflected by the target object to form a first echo beam, and the second probe beam is reflected by the target object to form a second echo beam. Along the transmission direction of the first and second echo beams, the wavelength division element 130 is located upstream of the first detector 112 and the second detector 122. The wavelength division element 130 is used to receive the first and second echo beams and to divide them into two beams for output. The wavelength division element 130 of this application can be a wavelength multiplexer, a dichroic mirror, or other components capable of combining and separately outputting light of different wavelengths.

[0053] exist Figure 1 As shown, the wavelength splitter 130 is a dichroic mirror, which can separate light beams according to wavelength. Its two sides are coated with a filter film and an anti-reflection film, respectively. The dichroic mirror exhibits high transmittance or high reflectivity for light beams of different wavelengths, thus it can be used to split / combine first and second echo beams of different wavelengths. Furthermore, by adaptively adjusting the wavelengths of the first and second probe beams using a dichroic mirror, it is possible to achieve almost complete transmission of one of the first and second echo beams while almost complete reflection of the other. This results in advantages such as high transmittance, accurate wavelength positioning, and low light energy loss.

[0054] The first echo light is transmitted through the wavelength division element 130 and received by the first detector 112. The second echo light is reflected by the wavelength division element 130 and received by the second detector 122. The first detector 112 is used to receive the first echo light so that the subsequent signal processing circuit can determine the distance of the target object relative to the lidar 100 based on the time difference between the transmission and reception of the first detector light and the first echo light. The first detector 122 can be an APD (Avalanche Photodiode), SPAD (single photon avalanche diode), or SiPM (Silicon photomultiplier), a high-sensitivity detector with single-photon sensitivity, etc. The second detector 122 is used to receive the second echo light and the corresponding local oscillator light to perform coherent detection to obtain a beat frequency signal, which allows the subsequent signal processing circuit to obtain the velocity of the target object relative to the lidar 100 based on the beat frequency signal. The second detector 112 is a coherent photodetector; for example, the second detector 112 can be a Ge-Si photodetector, or an InGaAs photodetector, or a balanced photodetector composed of them.

[0055] In this embodiment, the aforementioned continuous wave signal is a constant-frequency continuous wave signal. Thus, the frequency of the beat frequency signal acquired by the first detector 112 is the Doppler beat frequency, also known as the velocity beat frequency. The signal processing circuit can directly obtain the velocity of the target object relative to the lidar 100 based on this Doppler beat frequency. Of course, in other embodiments of this application, the aforementioned continuous wave signal can also be a frequency-modulated continuous wave signal. However, the frequency obtained in the latter way does not directly represent the velocity, but rather is the result of the coupling of the distance beat frequency and the Doppler beat frequency, such as the sum of the distance beat frequency and the Doppler beat frequency, or the absolute value of the difference between the distance beat frequency and the Doppler beat frequency. For example, when the frequency-modulated continuous wave signal is a triangular wave sweep signal, it is necessary to calculate the Doppler beat frequency based on the frequency values ​​of the beat frequency signals corresponding to the upper and lower sweep portions of the local oscillator signal, and then obtain the velocity of the target object relative to the lidar 100. When obtaining the velocity of a high-speed target object at close range, the process of obtaining the Doppler beat frequency is more complex because the relationship between the distance beat frequency and the Doppler beat frequency cannot be clearly defined. In contrast, the constant-frequency continuous wave signal in this embodiment allows the beat frequency signal to represent only the Doppler beat frequency, thus overcoming the aforementioned shortcomings. Therefore, while meeting the goal of obtaining the velocity of the target object, it also simplifies the complexity of the system. It should be noted that "constant frequency" as used in this application means a constant frequency.

[0056] In this embodiment, the lidar 100 also includes an analog-to-digital converter (ADC) connected to the second detector 122, the sampling rate of which is no higher than 200 Msps. Since the continuous wave uses a constant-frequency continuous wave, the frequency of the beat frequency signal output by the second detector 122 is the Doppler beat frequency. Because there is no range beat frequency, compared to the traditional FMCW lidar 100 which uses a frequency-modulated continuous wave for detection and requires a high-speed ADC for sampling, this embodiment can achieve sampling using an ADC with a low sampling rate. Generally, the Doppler beat frequency corresponding to the second echo light is lower than 100MHz, so an ADC with a sampling rate of less than or equal to 200 Msps can be used for sampling.

[0057] It is worth noting that in this embodiment, the first and second detection beams are emitted as a single beam outside the lidar 100 to detect the target object, ensuring that the speed obtained based on the first detection beam and the distance obtained based on the second detection beam correspond to the same target object. Specifically, the aforementioned wave-splitting element 130 is also disposed in the optical path of the first and second detection beams, and is used to receive the first and second detection beams, combine them, and output the combined first and second detection beams. Please refer to... Figure 1In this embodiment, the wavelength division multiplexing element 130 employs a dichroic mirror, comprising two opposing surfaces: a first surface 131 and a second surface 132. The first probe light emitted by the first laser 111 in the first transceiver module strikes the first surface 131 and is transmitted through it to the target object. Conversely, the second probe light emitted by the second laser 121 in the second transceiver module strikes the second surface 132 and is reflected by it, forming a coaxial optical path with the first probe light to reach the target object. The first and second echoes, formed by reflections from the target object, return along the paths of the first and second probe lights, respectively.

[0058] The lidar 100 also includes a first reflector 151, a first lens module 161, and a second lens module 162. Please refer to [link / reference needed]. Figure 1 Along the transmission direction of the first probe light, a first reflector 151 is located between the first laser 111 and the wavelength division element 130. The first reflector 151 reflects the first probe light to the wavelength division element 130, so that the first probe light and the second probe light are combined via the wavelength division element 130. The first reflector 151 can be a structure with a reflective surface formed by coating, or it can be an optically total internal reflection medium. This application does not specifically limit its structure, as long as it can achieve the above functions. Along the transmission direction of the first probe light, a first lens module 161 is located upstream of the wavelength division element 130, for example... Figure 1 As shown, the first lens module 161 is located between the first laser 111 and the first reflector 151; the first lens module 161 includes at least one lens and is used to collimate the first probe light. The collimation function of the first lens module 161 can reduce the divergence angle of the first probe light, so that the first probe light is emitted in an approximately parallel manner.

[0059] In some embodiments, the first lens module 161 may include a fast-axis collimation module and a slow-axis collimation module; for example, the fast-axis collimation module includes a fast-axis collimation lens, and the slow-axis collimation module includes a slow-axis collimation lens. By using monolithic lenses for both the fast and slow collimation lenses, the structure can be simplified, the difficulty of light adjustment can be reduced, and mass production assembly can be facilitated. Along the transmission direction of the first echo light, the second lens module 162 is located between the wavelength division element 130 and the first detector 112. The second lens module 162 includes at least one lens and is used to receive and focus the first echo light. In this embodiment, along the first direction shown in the figure, the second lens module 162 is located on the side of the first reflector 151 opposite to the wavelength division element 130. This first direction is the opposite direction in which the first reflector 151 reflects the first detector light. When viewed along the first direction, the cross-sectional profile of the second lens module 162 covers the first reflector 151. Generally, the spot size of the first probe light emitted by the first laser 111 is small, and the volume of the first reflecting mirror 151 used to reflect the first probe light is also small. However, the spot size of the first echo light entering the lidar 100 is larger. After being split by the beam splitter 130, part of the light falls on the first reflecting mirror 151 and is reflected, while part falls outside the first reflecting mirror 151 and further falls on the second lens module 162, where it is focused onto the photosensitive surface of the second detector 122. In this embodiment, the first reflecting mirror 151 allows the optical paths of the first probe light and the first echo light to be split at this location, thereby avoiding the interference of the high-energy pulse wave signal on the first detector 112 caused by the first laser 111 and the first detector 112 being too close. It should be noted that the "leader light" mentioned in this application refers to the beam of light that does not exit outside the lidar 100, but falls on the first detector 112 within the lidar 100 in the form of reflection or scattering.

[0060] Similarly, the lidar 100 also includes a third lens module 163. Located upstream of the wave-splitting element 130 along the transmission direction of the second probe light, the third lens module 163 includes at least one lens and is used to collimate the second probe light. The collimation effect of the third lens module 163 reduces the divergence angle of the second probe light, causing it to exit in an approximately parallel manner. The third lens module 163 can use the same or similar structure as the first lens module 161, which will not be described in detail here. Furthermore, in this embodiment, the third lens module 163 is also used to focus the second echo light output by the wave-splitting element 130, so that the focused second echo light enters the second detector 122.

[0061] In summary, this application incorporates two optical transceiver modules in the lidar 100. The first optical transceiver module 110 generates a first detection light, and the second optical transceiver module 120 generates a second detection light. The first and second detection lights are emitted as a single beam outside the lidar 100, one being a pulse wave signal and the other a continuous wave signal. A wavelength division element 130 receives the first and second echo lights and splits them into a first echo light propagating towards the first detector 112 and a second echo light propagating towards the second detector 122. Thus, the lidar 100 of this application can perform distance detection using the pulse wave signal and velocity detection using the continuous wave signal. Compared to the ToF lidar 100, this lidar 100 satisfies the requirement of detecting both distance and velocity within a single frame of data, thereby achieving higher timeliness. Furthermore, compared to the traditional FMCW lidar 100 which uses frequency-modulated continuous wave for detection and requires a high-speed analog-to-digital converter for sampling, this lidar 100 can achieve sampling using an analog-to-digital converter with a lower sampling rate, thereby reducing the overall device cost.

[0062] It should be understood that even though the above embodiments are described with the wavelength division element 130 located in the optical path of the first probe light and the second probe light as an example, this application is not limited to this. In other embodiments of this application, the wavelength division element 130 may not be located in the optical path of the first probe light and the second probe light. Accordingly, the first probe light and the second probe light are combined into a beam of light in other ways for emission.

[0063] For example, please refer to Figure 2 It shows a schematic diagram of a lidar 100 provided in another embodiment of this application, the main difference between this embodiment and the previous embodiment being: Figure 2 In the illustrated embodiment, the wavelength division element 130 is no longer used to combine the first probe light and the second probe light, but instead the combination of the first probe light and the second probe light is achieved by a wavelength combining element 140.

[0064] Specifically, the lidar 100 includes the aforementioned first optical transceiver module 110, second optical transceiver module 120, wavelength division multiplexing element 130, and wavelength multiplexing element 140. The first optical transceiver module 110 and the second optical transceiver module 120 are respectively connected to… Figure 1The first optical transceiver module 110 and the second optical transceiver module 120 in the illustrated embodiment are the same and will not be described again here. A beam combiner element 140 is disposed downstream of the first laser 111 and the second laser 121 along the transmission direction of the first and second probe beams. It receives the first and second probe beams and combines them into a single beam, so that the combined beam is then directed towards the target object for detection. The beam combiner element 140 can be a diffraction grating type beam combiner element, a prism type beam combiner element, a waveguide type beam combiner element, etc., and this application does not impose any limitations.

[0065] In this embodiment, the lidar 100 may further include a second reflector 152. Along the transmission direction of the first probe light, the second reflector 152 is located downstream of the multiplexing element 140. The second reflector 152 reflects the combined first and second probe lights, so that the combined optical signal is directed towards the target object. The first and second echo lights propagate to the wave splitting element with the portion of the light spot falling outside the second reflector 152, thereby achieving the reception of the first and second echo lights. The specific structure of the second reflector 152 can be referred to the first reflector 151 described above, and will not be repeated here.

[0066] Furthermore, the lidar 100 also includes a fourth lens module 164 and a fifth lens module 165. Specifically, along the transmission direction of the first probe light, the fourth lens module 164 is located downstream of the multiplexing element 140. The fourth lens module 164 includes at least one lens for collimating the combined first and second probe lights. The collimation effect of the first lens module 161 can reduce the divergence angle between the first and second probe lights, allowing them to exit in an approximately parallel manner. In some embodiments, the fourth lens module 164 may include a fast-axis collimation module and a slow-axis collimation module; for example, the fast-axis collimation module includes a fast-axis collimating lens, and the slow-axis collimation module includes a slow-axis collimating lens. By using monolithic lenses for the fast and slow collimating lenses, the structure can be simplified, the difficulty of light adjustment can be reduced, and mass production assembly can be facilitated. Along the transmission direction of the first echo light, the fifth lens module 165 is located upstream of the wave splitter element 130, and includes at least one lens. The fifth lens module 165 is used to receive the first echo light and the second echo light, and to focus the first echo light and the second echo light. In this embodiment, along the first direction shown in the figure, the fifth lens module 165 is disposed between the second reflector 152 and the wave splitter element 130, and the first direction is the opposite direction in which the second reflector 152 reflects the first probe light; when viewed along the first direction, the cross-sectional profile of the fifth lens module 165 covers the second reflector 152. Generally, the spot size of the first detection light emitted by the first laser 111 is small, and the volume of the second reflector 152 used to reflect the first detection light is also small; while the spot size of the first echo light entering the lidar 100 is larger. After being split by the beam splitter 130, part of the light falls on the second reflector 152 and is reflected, and part of the light falls outside the second reflector 152 and further falls on the fifth lens module 165, so that it is focused by the fifth lens module 165 onto the photosensitive surface of the second detector 122.

[0067] exist Figure 2 In the illustrated embodiment, the wavelength division multiplexing element 130, the first detector 112 in the first optical transceiver module 110, and the second detector 122 in the second optical transceiver module 120 can be respectively connected to... Figure 1 The structures shown in the embodiments are the same and will not be described again here.

[0068] With the above Figure 1 The corresponding embodiments are similar. The lidar 100 provided in this embodiment also satisfies the ability to detect both distance and speed in a single frame of data, and has high timeliness.

[0069] For example, please refer to Figure 3 It shows a schematic diagram of a lidar 100 provided in another embodiment of this application, which is similar to the one described above. Figure 2The main difference between the illustrated embodiments is: Figure 3 In the illustrated embodiment, a beam splitter 170 replaces the aforementioned second reflector 152. Specifically, along the transmission direction of the first probe light, the beam splitter 170 is located downstream of the multiplexing element 140, and along the transmission direction of the first echo light, the beam splitter 170 is located upstream of the multiplexing element 130. The beam splitter 170 includes a reflective region 172 and a transmission region 171. The reflective region 172 is used to reflect the combined first and second probe lights, and the transmission region 171 is used to transmit the first and second echo lights. Optionally, when viewed along the first direction, the reflective region 172 is circular, and the transmission region 171 is arranged around the reflective region 172.

[0070] With the above Figure 1 The corresponding embodiments are similar. The lidar 100 provided in this embodiment also satisfies the ability to detect both distance and speed in a single frame of data, and has high timeliness.

[0071] It is worth noting that the lidar 100 provided in the above embodiments all adopt a coaxial optical path architecture, that is, the detection and echo optical paths are the same, only separated by a special structure inside the lidar 100; however, it should be understood that in other embodiments of this application, the lidar 100 can also adopt an off-axis optical path architecture, that is, the optical path downstream of the reflector on the detection optical path does not coincide with the optical path upstream of the wave splitter element on the echo optical path. For example, with Figure 1 Taking the illustrated embodiment as an example, in other embodiments, a multiplexing element 140 can be provided in the transmitting optical path, and a wavelength splitting element 130 can be provided in the returning optical path. The multiplexing element 140 and the wavelength splitting element 130 are independent of each other. The first laser 111 and the second laser 121 correspond to the multiplexing element 140, and the first detector 112 and the second detector 122 correspond to the wavelength splitting element 130; in this way, the above-mentioned solution can be achieved. For example, taking... Figure 2 Taking the illustrated embodiment as an example, in other embodiments, the wave-splitting element 130 may not be placed at a position collinear with the second reflector 152 along the first direction, but may be placed at another position; in this way, the above solution can be achieved.

[0072] It is worth mentioning that, based on any of the above embodiments, there can be multiple first optical transceiver modules 110 and second optical transceiver modules 120, which correspond one-to-one. Each pair of corresponding first optical transceiver modules 110 and second optical transceiver modules 120 work together to complete the detection of distance and speed.

[0073] Furthermore, based on any of the above embodiments, the lidar 100 of this application may also be provided with a third optical transceiver module. Specifically, the third optical transceiver module includes a third laser and a third detector. The third laser is used to generate a third detection light as a pulse wave signal for detecting target objects. The third detector is used to receive the third echo light formed by the third detection light reflected by the target object. The third optical transceiver module is used for distance measurement. When combined with the first optical transceiver module 110 and the second optical transceiver module 120, the first optical transceiver module 110 and the second optical transceiver module 120 correspond one-to-one to realize the detection of the distance and velocity of target objects in the same detection area. The third optical transceiver module is used to realize the measurement of the distance and velocity of target objects in another detection area. For example, in some embodiments, the lidar 100 includes multiple pairs of first optical transceiver modules 110 and second optical transceiver modules 120, and at least one third optical transceiver module. The detection field of view corresponding to the third optical transceiver module is the edge field of view of the lidar 100. The detection field of view corresponding to each pair of first optical transceiver modules 110 and second optical transceiver modules 120 is a detection field of view closer to the center of the field of view than the detection field of view of the third optical transceiver module. The target object in the center detection field of view is often the target object that needs to be focused on. The distance and speed of the target object in this area have a strong influence on the mobile device 300 equipped with the lidar 100, and the motion state planning of the mobile device 300 has high requirements for the timeliness of information in this area. Conversely, the distance and speed of the target object in the edge detection field of view have a smaller influence on the mobile device 300 equipped with the lidar 100. Therefore, distance detection can be performed by the third optical transceiver module, which helps to simplify the overall architecture of the lidar 100 to a certain extent.

[0074] Please refer to the reference. Figures 1 to 4 This application also proposes a mobile device 300, which includes a movable main body 200 and a lidar 100 installed on the movable main body 200. The specific structure of the lidar 100 is as described in the above embodiments. Since this mobile device 300 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here. The mobile device 300 can be a car, ship, aircraft, etc., and there is no limitation thereto.

[0075] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this application. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0076] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A lidar, characterized in that, include: The first optical transceiver module includes a first laser and a first detector, wherein the first laser is used to generate a first probe light; The second optical transceiver module includes a second laser and a second detector. The second laser is used to generate a second detection light. One of the first detection light and the second detection light is a pulse wave signal used to determine the distance of the target object relative to the lidar, and the other is a continuous wave signal used to determine the speed of the target object relative to the lidar. The continuous wave is a constant frequency continuous wave, and the wavelength of the second detection light is different from that of the first detection light. as well as A wavelength division element is located upstream of the first detector and the second detector along the transmission direction of the first echo and the second echo. The wavelength division element is used to receive the first echo and the second echo and divide them to output the first echo and the second echo. The first echo is formed by the reflection of the first detection light by the target object, and the second echo is formed by the reflection of the second detection light by the target object. The first detector is used to receive the first echo light, and the second detector is used to receive the second echo light.

2. The lidar as described in claim 1, characterized in that, The wavelength division element is a dichroic mirror.

3. The lidar as described in claim 1, characterized in that, The wavelength division element is also used to receive the first probe light and the second probe light, combine them, and output the combined first probe light and the second probe light.

4. The lidar as described in claim 3, characterized in that, It also includes the first reflecting mirror; Along the transmission direction of the first probe light, the first reflector is located between the first laser and the wavelength division element, and the first reflector is used to reflect the first probe light to the wavelength division element.

5. The lidar as described in claim 4, characterized in that, It also includes a first lens module; Along the transmission direction of the first probe light, the first lens module is located upstream of the wavelength division element. The first lens module includes at least one lens and is used to collimate the first probe light.

6. The lidar as described in claim 4, characterized in that, It also includes a second lens module; Along the transmission direction of the first echo light, the second lens module is located between the wavelength division element and the first detector. The second lens module includes at least one lens and is used to receive the first echo light and focus the first echo light. Along the first direction, the second lens module is disposed on the side of the first reflector away from the wavelength division element, and the first direction is the opposite direction of the first reflector reflecting the first probe light.

7. The lidar as described in claim 3, characterized in that, It also includes a third lens module; Along the transmission direction of the second probe light, the third lens module is located upstream of the wavelength division element. The third lens module includes at least one lens and is used to collimate the second probe light.

8. The lidar as described in claim 1, characterized in that, It also includes multiplexing elements; The beam combiner is used to receive the first detection light and the second detection light, and combine them into a single beam of light to detect the target object.

9. The lidar as described in claim 8, characterized in that, It also includes a second reflecting mirror; Along the transmission direction of the first probe light, the second reflector is located downstream of the combining element, and the second reflector is used to reflect the combined first probe light and the second probe light.

10. The lidar as described in claim 9, characterized in that, It also includes a fourth lens module; Along the transmission direction of the first probe light, the fourth lens module is located downstream of the multiplexing element. The fourth lens module includes at least one lens and is used to collimate the first probe light and the second probe light after multiplexing.

11. The lidar as described in claim 9, characterized in that, It also includes a fifth lens module; Along the transmission direction of the first echo light, the five-lens module is located upstream of the wave splitter element. The fifth lens module includes at least one lens and is used to receive the first echo light and the second echo light, and to focus the first echo light and the second echo light.

12. The lidar as described in claim 11, characterized in that, Along the first direction, the fifth lens module is disposed between the second reflector and the wave splitter element, and the first direction is the opposite direction of the second reflector reflecting the first probe light and the second probe light; When viewed along the first direction, the cross-sectional profile of the fifth lens module covers the second reflector.

13. The lidar as described in claim 8, characterized in that, It also includes a beam splitter; Along the transmission direction of the first probe light, the beam splitter is located downstream of the wave combiner; along the transmission direction of the first echo light, the beam splitter is located upstream of the wave combiner. The beam splitter includes a reflective region and a transmission region. The reflective region is used to reflect the first and second probe beams after beam combining, and the transmission region is used to transmit the first and second echo beams. The transmission zone is arranged around the reflection zone.

14. A mobile device, characterized in that, include: A movable main body; as well as The lidar as described in any one of claims 1 to 13.

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