Light source module and laser radar

Abstract

The embodiment of the invention discloses a light source module and a laser radar. The light source module comprises a light source module, a light splitting chip and a light amplification module. The light splitting chip comprises a cladding, an incident port, a plurality of emergent ports, a first coupler and a first light receiving element. The first coupler is located on a light path from the incident port to the emergent port and comprises a first port, a second port and a third port, the first port and the second port are located on the light path from the incident port to the emergent port, the first port is located on the upstream of the second port in the transmission direction of a laser beam from the incident port to the emergent port, and the third port is located on the downstream of the third port in the transmission direction of the laser beam from the emergent port to the incident port. The first coupler is configured to output an optical signal input via the second port via the first port and the third port. The first light receiving element is used for receiving the optical signal output by the third port. The optical amplification module comprises a plurality of semiconductor optical amplifiers in one-to-one correspondence with the emergent ports. The light source module can improve the current situation that the light path coupling condition of the light splitting chip and the light amplification module cannot be monitored at present.

Description

Technical Field

[0001] This application relates to the field of laser detection technology, and in particular to a light source module and a lidar. Background Technology

[0002] Generally, a lidar system includes a housing, a light source module, a transceiver module, and a scanning module. The housing serves as the mounting base for the remaining structures within the lidar system, housing the light source module, transceiver module, and scanning module. The light source module generates an emitted light beam to detect target objects. The transceiver module receives the emitted light beam and directs the detected light towards the scanning module; the detected light is at least a portion of the emitted light beam. The scanning module includes a scanning device that receives and deflects the detected light, allowing it to exit the lidar system. The scanning device can rotate relative to the housing, enabling the detected light to form a specific detection field of view outside the lidar system, thus achieving target object detection. The detected light is reflected by the target object to form an echo light directed towards the lidar system, which is reflected by the scanning module to the transceiver module; that is, the transceiver module also receives the echo light.

[0003] In related technologies, the light source module of a lidar includes a light source module, a beam splitter chip, and an optical amplification module. The laser beam generated by the light source module is split by the beam splitter chip to obtain multiple emitted beams. Each emitted beam is further amplified by the optical amplification module, enabling the lidar to perform detection based on these amplified emitted beams. The optical amplification module can be an amplifier array composed of multiple semiconductor optical amplifiers (SOAs). Because the receiving port of the SOA for receiving the emitted beam is very small, the beam splitter chip and the SOA require very precise optical path coupling. For example, after mounting the light source module, beam splitter chip, and optical amplification module in a preset position, the position of the lens located between the receiving port of the beam splitter chip and the SOA needs to be precisely adjusted to ensure that the lens focus falls on the receiving port. Summary of the Invention

[0004] There are no corresponding methods in the relevant technologies to monitor the optical path coupling between the beam splitter chip and the SOA. Therefore, the debugging efficiency of the above optical path coupling process is low, and there is a risk of low optical coupling efficiency when the laser beam enters the SOA.

[0005] The embodiments of this application aim to provide a light source module and a lidar to improve the current situation where the optical path coupling between the beam splitter chip and the SOA cannot be monitored.

[0006] This application provides a light source module, which includes a light source module, a beam splitter chip, and an optical amplification module. The light source module is used to generate a laser beam. The beam splitter chip includes a cladding, an incident port, a plurality of exit ports, a first coupler, and a first light receiving element all disposed on the cladding. The beam splitter chip is configured to receive the laser beam through the incident port, so that the laser beam enters the beam splitter chip and is split, and to output the emitted beam obtained by splitting the laser beam through the exit ports. The first coupler is located on the optical path from the incident port to the exit port and includes a first port, a second port, and a third port. The first port and the second port are both located on the optical path from the incident port to the exit port. Along the transmission direction of the laser beam from the incident port to the exit port, the first port is located upstream of the second port. The first coupler is configured to output an optical signal input through the second port through the first port and the third port. The first light receiving element is used to receive the optical signal output through the third port. The optical amplification module includes multiple semiconductor optical amplifiers, each of which corresponds to one of the emission ports. The semiconductor amplifiers are used to receive and amplify the emitted light beam.

[0007] In some embodiments, the beam splitter chip includes a beam splitting module disposed on the cladding layer. The beam splitting module is used to split the laser beam. The beam splitting module includes a first input terminal and a plurality of first output terminals. The first input terminal is connected to the incident port and is used to receive the laser beam. The first output terminals are used to output the emitted beam obtained by the beam splitting module from the laser beam. Each of the exit ports is connected to a first output terminal. The semiconductor optical amplifier includes an optical transmission waveguide extending along a first direction. The optical transmission waveguide includes a receiving end face and an emitting end face opposite to each other along the first direction. The receiving end face is used to receive the emitted beam, and the emitting end face is used to emit the amplified emitted beam. The direction in which the emitted beam is incident on the receiving end face is a second direction, and the second direction has a first acute angle with the normal of the receiving end face.

[0008] In some embodiments, the first coupler is disposed between the incident port and the beam splitter module.

[0009] In some embodiments, the first coupler further includes a fourth port, and the first coupler is configured to output an optical signal input via the first port via the second port and the fourth port. The beam splitter also includes a second light-receiving element disposed on the cladding, the second light-receiving element being used to receive the optical signal output via the fourth port.

[0010] In some embodiments, the first coupler is a directional coupler; the first light-receiving element and the second light-receiving element are connected to different ends of the same waveguide, or the first light-receiving element and the second light-receiving element are connected to different waveguides.

[0011] In some embodiments, the beam splitter chip further includes a second coupler and a second light-receiving element. The second coupler is disposed in the cladding and located in the optical path from the incident port to the exit port, including a fifth port, a sixth port, and a seventh port. The fifth port and the sixth port are both located in the optical path from the exit port to the incident port. Along the transmission direction of the laser beam from the incident port to the exit port, the fifth port is upstream of the sixth port. The second coupler is configured to output optical signals input via the fifth port via the sixth and seventh ports. The second light-receiving element is disposed in the cladding and is used to receive optical signals output via the seventh port.

[0012] In some embodiments, the first coupler further includes a fourth port, and the first coupler is configured to output an optical signal input via the first port via the second port and the fourth port. The beam splitter chip further includes a beam combiner disposed on the cladding, the beam combiner including a second input terminal, a third input terminal, and a second output terminal, the beam combiner being configured to output an optical signal input via the second input terminal and / or the third input terminal via the second output terminal, the second input terminal being connected to the third port, and the third input terminal being connected to the fourth port. The first light receiving element is used to receive the optical signal output via the second output terminal.

[0013] In some embodiments, the beam splitter chip further includes a second coupler and a beam combiner. The second coupler is disposed in the cladding and located on the optical path from the incident port to the exit port, including a fifth port, a sixth port, and a seventh port. The fifth port and the sixth port are both located on the optical path from the exit port to the incident port. Along the transmission direction of the laser beam from the incident port to the exit port, the fifth port is upstream of the sixth port. The second coupler is configured to output optical signals input via the fifth port via the sixth port and the seventh port. The beam combiner is disposed in the cladding and includes a second input terminal, a third input terminal, and a second output terminal. The beam combiner is configured to output optical signals input via the second input terminal and / or the third input terminal via the second output terminal. The second input terminal is connected to the third port, and the third input terminal is connected to the seventh port. The first receiving element is used to receive the optical signal output via the second output terminal.

[0014] In some embodiments, the first light-receiving element includes a photodetector or a grating; the second light-receiving element includes a photodetector or a grating.

[0015] This application also provides a lidar, which includes a housing and the aforementioned light source module, wherein the light source module is housed within the housing.

[0016] The technical advantages of this application are as follows: The light source module provided in this application includes a light source module, a beam splitter chip, and an optical amplification module. The beam splitter chip includes a cladding layer, an incident port, multiple exit ports, a first coupler, and a first light-receiving element. The first coupler is disposed on the optical path from the incident port to the exit ports, and includes a first port, a second port, and a third port. Both the first and second ports are located on the optical path from the incident port to the exit ports. The first coupler is configured to output optical signals input via the second port via the first and third ports. The first light-receiving element is connected to the third port to receive optical signals output via the third port.

[0017] Thus, when coupling the beam splitter and the optical amplification module, the SOA in the optical amplification module can be used to radiate laser light. The laser light radiated by the SOA includes a first beam emitted from the receiving end of the SOA towards the beam splitter. The first beam enters the beam splitter through the output port for transmission. When the first beam reaches the first coupler, part of its energy will be output from the first port, and part of its energy will be output from the third port, and further transmitted to the first receiving element connected to the third port. Therefore, the coupling status between the beam splitter and the optical amplification module can be monitored based on the optical signal energy obtained by the first receiving element. That is, the light source module provided in this application can improve the current situation in related technologies where the optical path coupling status between the beam splitter and the optical amplification module cannot be monitored, which is beneficial to improving the debugging efficiency of the above-mentioned optical path coupling process. Attached Figure Description

[0018] 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 these drawings without creative effort.

[0019] Figure 1 These are schematic diagrams of light source modules provided in some embodiments of this application;

[0020] Figure 2 This is a schematic diagram of the optical path of a laser beam transmitted through a semiconductor optical amplifier;

[0021] Figure 3This is a schematic diagram of a beam splitter chip provided in some other embodiments of this application;

[0022] Figure 4 These are schematic diagrams of the beam splitting chips provided in other embodiments of this application;

[0023] Figure 5 These are schematic diagrams of the beam splitter chips provided in other embodiments of this application;

[0024] Figure 6 This is a schematic diagram of a lidar provided in some embodiments of this application.

[0025] Explanation of reference numerals in the attached figures:

[0026] 1. Light source module;

[0027] 100. Light source module; 110. Laser; 120. Isolator; 130. First lens; 140. Second lens;

[0028] 200, Spectrometer chip; 210, Cladding; 220, Incident port; 230, Spectrometer module; 240, Outgoing port; 250, First coupler; 260, First receiving element; 270, Second receiving element; 231, First input terminal; 232, First output terminal; 251, First port; 252, Second port; 253, Third port; 254, Fourth port;

[0029] 300, Optical amplification module; 310, Semiconductor optical amplifier; 320, Lens module; 311, Optical transmission waveguide; 301, Light receiving end face; 302, Light emitting end face;

[0030] 200b, beam splitter chip; 210b, cladding; 220b, incident port; 230b, beam splitter module; 240b, output port; 250b, first coupler; 260b, first receiving element; 270b, second receiving element; 280b, second coupler; 281b, fifth port; 282b, sixth port; 283b, seventh port;

[0031] 200c, beam splitter; 210c, cladding; 220c, incident port; 230c, beam splitter module; 240c, output port; 250c, first coupler; 260c, first receiving element; 261c, beam combiner;

[0032] 200d, beam splitter; 210d, cladding; 220d, incident port; 230d, beam splitter module; 240d, output port; 250d, first coupler; 260d, first receiving element; 280d, second coupler; 251d, first port; 252d, second port; 253d, third port; 261, beam combiner;

[0033] 2. LiDAR; 21. Housing. Detailed Implementation

[0034] 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.

[0035] In the following description, when referring to the accompanying drawings, the same numbers in different drawings denote the same or similar elements unless otherwise indicated. 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.

[0036] In related technologies, the light source module of a lidar includes a light source module, a beam splitter chip, and an optical amplification module. The source light signal generated by the light source module is split by the beam splitter chip to obtain multiple emitted beams. Each emitted beam is further amplified by the optical amplification module, allowing the lidar to detect based on these amplified beams. The optical amplification module can be an amplifier array composed of multiple optically independent arrays (SOAs). Because the receiving port of the SOA for receiving the emitted beam is very small, the beam splitter chip and the SOA require very precise optical path coupling. For example, after mounting the light source module, beam splitter chip, and optical amplification module in a preset position, the position of the lens located between the receiving port of the beam splitter chip and the SOA needs to be precisely adjusted to ensure that the lens focus falls on the receiving port. Related technologies lack corresponding methods to monitor the optical path coupling between the beam splitter chip and the SOA, resulting in low debugging efficiency in the optical path coupling process and a risk of low coupling efficiency when the laser beam enters the SOA.

[0037] The present application aims to provide a light source module to improve the current situation where the optical path coupling between the beam splitter chip and the SOA cannot be monitored. Compared with the light source modules in related technologies, the light source module provided in the present application is beneficial to improving the debugging efficiency of the above-mentioned optical path coupling process and improving the optical coupling efficiency when the laser beam enters the SOA.

[0038] Please see Figure 1The diagram illustrates a schematic of a light source module 1 provided in some embodiments of this application. The light source module 1 includes a light source module 100, a beam splitter chip 200, and an optical amplification module 300. The light source module 100 generates a laser beam to detect a target object based on the laser beam. The beam splitter chip 200 includes a cladding 210 and incident ports 220, multiple exit ports 240, a first coupler 250, and a first light-receiving element 260, all disposed on the cladding 210. The beam splitter chip 200 is configured to receive a laser beam via the incident ports 220, allowing the laser beam to enter and be split, and to output the emitted beam obtained by splitting the laser beam via the exit ports 240. The first coupler 250 is located on the optical path from the incident port 220 to the output port 240, and includes a first port 251, a second port 252, and a third port 253. Both the first port 251 and the second port 252 are located on the optical path from the incident port 220 to the output port 240. Along the transmission direction of the laser beam from the incident port 220 to the output port 240, the first port 251 is located upstream of the second port 252. The first coupler 250 is configured to output the optical signal input via the second port 252 via the first port 251 and the third port 253. The first light-receiving element 260 is used to receive the optical signal output via the third port 253. The optical amplification module 300 includes multiple SOA 310s, each corresponding to an output port 240. The SOA 310 is used to receive and amplify the emitted beam. It should be noted that the "target object" mentioned in this application refers to the target object detected by the lidar when detecting the external environment, including but not limited to: vehicles, pedestrians, ground, buildings, and vegetation. The phrase "a component is located on / on the optical path from the incident port to the exit port" in this application means that the optical signal can be transmitted to the exit port through the incident port and the component; for example, the first coupler 250 is located on the optical path from the incident port 220 to the exit port 240, meaning that the optical signal can be transmitted to the exit port 240 through the incident port 220 and the first coupler 250. The specific structure of the light source module 1 will be described in detail below with reference to the accompanying drawings.

[0039] For details regarding the aforementioned light source module 100, please refer to [link / reference]. Figure 1The light source module 100 generates a laser beam and outputs it to the beam splitter chip 200. In this embodiment, the light source module 100 includes a laser 110, an isolator 120, a first lens 130, and a second lens 140. The laser 110 generates the laser beam and can be a semiconductor laser, such as a distributed feedback laser or a distributed Bragg reflector laser. The isolator 120 is located between the laser 110 and the beam splitter chip 200 and isolates the light signal reflected back from the beam splitter chip 200 to prevent the reflected light signal from entering the laser 110 and affecting its normal operation. The first lens 130 is located between the laser 110 and the isolator 120 and collimates the laser beam output from the laser 110 so that the collimated laser beam enters the isolator 120 and is transmitted downstream via the isolator; the first lens 130 helps improve the optical coupling efficiency of the laser beam entering the isolator 120. The second lens 140 is disposed between the isolator 120 and the beam splitter 200. It is used to focus the laser beam output from the isolator 120 so that the focused laser beam enters the beam splitter 200. The arrangement of the second lens 140 helps to improve the optical coupling efficiency of the laser beam entering the beam splitter 200. It should be noted that the "optical coupling efficiency" mentioned in this application means the ratio of the optical power coupled into a component to the optical power before entering the component.

[0040] For more information on the aforementioned spectrometer chip 200, please refer to [link / reference needed]. Figure 1 The beam splitter 200 receives the laser beam output from the light source module 100 and splits it to output multiple emitted beams. The beam splitter 200 is an optical chip, which can be a silicon optical chip based on silicon waveguide technology, a silicon nitride optical chip based on silicon nitride waveguide technology, or an optical chip based on a composite silicon waveguide and silicon nitride waveguide technology. Specifically, the beam splitter 200 includes a substrate layer (not shown), a cladding layer 210, an incident port 220, multiple exit ports 240, a first coupler 250, and a first light-receiving element 260.

[0041] The substrate layer is the base material used to lay the cladding layer 210. In this embodiment, it is made of silicon. It is understood that in other embodiments of this application, the substrate layer can also be made of other suitable materials, such as silicon nitride. The cladding layer 210 is deposited or grown on the substrate layer and constitutes one of the main structures of the beam splitter chip 200, as well as the substrate on which the remaining components in the beam splitter chip 200 are attached. The aforementioned incident port 220, multiple exit ports 240, first coupler 250, and first light-receiving element 260 are all disposed in the cladding layer 210. The refractive index of the incident port 220, multiple exit ports 240, and first coupler 250 is greater than that of the cladding layer to ensure that the optical signal can be transmitted along the aforementioned devices within the cladding layer 210. The material of the cladding layer 210 is generally different from that of the substrate layer and can be made of materials such as silicon dioxide and / or silicon oxynitride.

[0042] The incident port 220 is embedded in the cladding layer 210 and is used to receive the laser beam output from the light source module 100, so that the laser beam can enter the beam splitter chip 200 for transmission. That is, the incident port 220 is the port in the beam splitter chip 200 used for laser beam input. In this embodiment, the incident port 220 is a mode converter, which is used to improve the mode field matching degree when the laser beam couples from the air into the beam splitter chip 200, which helps to reduce mode loss and thus improve the optical coupling efficiency when the laser beam enters the beam splitter chip 200. Of course, in other embodiments of this application, the incident port 220 can also be an end-face coupler or other devices that can be used to couple optical signals.

[0043] In this embodiment, the beam splitter chip 200 further includes a beam splitter module 230, which is disposed on the cladding layer 210 and connected to the incident port 220. The beam splitter module 230 receives the laser beam coupled into the beam splitter chip 200 via the incident port 220 and splits it to obtain multiple emission beams; that is, the beam splitter chip 200 achieves beam splitting of the optical signal through the beam splitter module 230. Specifically, the beam splitter module 230 includes a first input terminal 231 and multiple first output terminals 232. The first input terminal 231 is connected to the incident port 220 to receive the laser beam and is the input terminal of the beam splitter module 230; the first output terminals 232 are used to output the split emission beams after the beam splitter module 230 has split the laser beam and are the output terminals of the beam splitter module 230. In this embodiment, the beam splitter module 230 includes a first beam splitter and multiple second beam splitters. For example, the first beam splitter is a 1*2 beam splitter, with its input terminal being the aforementioned first input terminal 231, and each output terminal of the first beam splitter connected to a second beam splitter; the second beam splitter is also a 1*2 beam splitter, with its input terminal connected to the output terminal of the first beam splitter, and its output terminal being the aforementioned first output terminal 232. It is understood that even though this embodiment uses a beam splitting module 230 comprising one first beam splitter and two second beam splitters as an example for illustration, it should be understood that this application is not limited to this, and the specific structure of the beam splitting module 230 is actually diverse, as long as the beam splitting module 230 as a whole can achieve the function of splitting a laser beam into multiple emission beams. For example, in other embodiments of this application, the beam splitting module 230 may include only one 1*N (N≥2) beam splitter; as another example, in some other embodiments of this application, the beam splitting module 230 may include the aforementioned first beam splitter, second beam splitter, and a third beam splitter connected in series between the output of the first beam splitter and the input of the second beam splitter; these will not be detailed here. It should be noted that "multiple" in this application means two or more.

[0044] The emission port 240 is also embedded in the cladding 210. Each of the first output terminals 232 is connected to an emission port 240, which is used to receive the emitted beam output through the first output terminal 232 and output the emitted beam outside the beam splitter 200. That is, the emission port 240 is the port in the beam splitter 200 used for laser beam output. The emission port 240 can adopt a similar structure to the incident port 220; for example, in this embodiment, the incident port 220 is a mode converter, which is used to improve the mode field matching degree when the emitted beam enters the air from the beam splitter 200, which helps to reduce mode loss and thus improve the optical coupling efficiency when the emitted beam exits the beam splitter 200.

[0045] For the aforementioned optical amplification module 300, please refer to [link / reference needed]. Figure 1 The optical amplification module 300 is located downstream of the beam splitter 200 and is used to amplify the emitted beams output by the beam splitter 200. Specifically, the optical amplification module 300 includes multiple optical arrays (SOA) 310s, each SOA 310 corresponding to an output port 240 of the beam splitter 200, to receive and amplify the emitted beams emitted from the corresponding output port 240. Preferably, to ensure that the emitted beams can enter the SOA 310 with high optical coupling efficiency, the optical amplification module 300 also includes multiple lens modules 320s, each corresponding to one of the SOA 310s, which are used to converge the emitted beams output from the beam splitter 200 into the SOA 310s. Specifically, the lens module 320 may include a third lens and a fourth lens; wherein, the third lens is disposed between the beam splitter 200 and the SOA 310, and is used to collimate the emitted beam output by the beam splitter 200; the fourth lens is disposed between the third lens and the SOA 310, and is used to converge the collimated emitted beam into the SOA 310. Of course, in some other embodiments, the lens module 320 may also include only one lens to converge the emitted beam into the SOA 310.

[0046] Please see Figure 2 The figure illustrates the optical path of a laser beam propagating in an SOA 310. As shown, the SOA 310 includes an optical transmission waveguide 311, which serves as the medium for transmitting the emitted beam. The optical transmission waveguide 311 extends along a first direction U and includes a receiving end face 301 and an emitting end face 302 disposed opposite to each other along the first direction U. The receiving end face 301 receives the emitted beam, allowing it to enter the SOA 310 for amplification, while the emitting end face 302 emits the emitted beam, allowing the amplified beam to propagate downstream. The emitted beam exits from the emission port 240 in a second direction V, which is also the propagation direction of the emitted beam when it is incident on the receiving end face 301. A first acute angle α exists between the normal L of the receiving end face 301 and the second direction V. The setting of the first acute angle α can prevent the reflected signal from returning to the beam splitter 200 along the original path when part of the emitted beam is reflected at the receiving end face 301, thereby avoiding interference from this part of the reflected signal to the original optical path. Furthermore, there is a second acute angle β between the first direction U and the normal L of the receiving end face 301. In this embodiment, the refractive index of air is η1, the refractive index of the optical transmission waveguide 311 is η2, and the first acute angle α and the second acute angle β are configured to satisfy: η1×sinα=η2×sinβ. Therefore, after being amplified by SOA310, the emitted beam will still exit from the emitting end of SOA 310 along the second direction V.

[0047] Since the transmission of the beam from the beam splitter 200 to the SOA 310 involves beam coupling, it is necessary to ensure that the transmitted beam couples into the SOA 310 with high optical coupling efficiency to reduce energy loss during optical signal transmission and, to some extent, reduce the power of the SOA 310. Based on this, the beam splitter 200 also includes the aforementioned first coupler 250 and first receiving element 260, and the beam coupling process is monitored through the first coupler 250 and the first receiving element 260.

[0048] Specifically, the first coupler 250 is embedded in the cladding 210 and is located in the optical path from the incident port 220 to the exit port 240. In this embodiment, the first coupler 250 is located between the incident port 220 and the beam splitter 230, and includes a first port 251, a second port 252, and a third port 253. The first port 251 and the second port 252 are both located in the optical path from the incident port 220 to the exit port 240. Along the direction of optical signal transmission from the incident port 220 to the exit port 240, the first port 251 is located upstream of the second port 252; the third port 253 is not located in the optical path from the incident port 220 to the exit port 240. The first coupler 250 is configured to output the optical signal input via the second port 252 via the first port 251 and the third port 253. Accordingly, given the principle of optical path reversibility, the first coupler 250 is also configured to output the optical signal input via the first port to the subsequent beam splitter 230 and the output port 240 via the second port 252. It should be noted that, to ensure that most of the energy of the laser beam (or emitted beam) flows to the output port 240 when passing through the first coupler 250, the first port 251 should have a significantly higher coupling ratio than the third port 253; for example, in some embodiments, the coupling ratio of the first port 251 to the third port 253 can be 99:1; and in other embodiments, the coupling ratio can be 995:5.

[0049] A first light-receiving element 260 is disposed on the cladding 210 and connected to the aforementioned third port 253. This first light-receiving element 260 is used to receive the optical signal output via the third port 253. In this embodiment, the first light-receiving element 260 includes a photodetector. Thus, when coupling the beam splitter 200 and the optical amplification module 300, the spontaneous emission laser characteristic of the SOA 310 can be utilized to control the SOA 310 to radiate laser light. The laser light radiated by the SOA includes a first beam emitted from the receiving end of the SOA (the end shown near the output port in the diagram) towards the beam splitter 200, and a second beam emitted from the emitting end of the SOA 310 (the end shown away from the output port in the diagram) downstream of the optical amplification module 300. Thus, the first beam will be transmitted sequentially through the lens module 320 to the output port 240 of the beam splitter 200, and further enter the beam splitter 200 for transmission through the output port 240. When the first beam is transmitted to the first coupler 250, part of its energy will be output from the first port 251, and part of its energy will be output from the third port 253, and further transmitted to the first light-receiving element 260 connected to the third port 253, i.e., the aforementioned photodetector. Therefore, the energy of the first beam entering the beam splitter 200 can be inferred from the photocurrent intensity output by the photodetector. When the photocurrent is at its maximum, the optical coupling efficiency between the beam splitter 200 and the optical amplification module 300 is the highest, thereby allowing monitoring of the optical coupling efficiency when the beam splitter 200 is coupled to the SOA 310. Of course, in other embodiments of this application, the first light-receiving element 260 can also be other devices, as long as they have the function of receiving optical signals. For example, in other embodiments, the first light-receiving element 260 can also be a grating; thus, when the first light beam enters the beam splitter 200 through the output port 240 and is transmitted to the first coupler 250, a small portion of the energy of the laser beam will be output from the third port 253 and further transmitted to the grating. The optical signal received by the grating can be further detected by an external component (such as an optical power meter) to measure the optical power. Therefore, the energy of the laser beam entering the beam splitter 200 can be inferred from the optical power output by the grating, thereby enabling the monitoring of the optical coupling efficiency when the light source module 100 is coupled to the beam splitter 200.

[0050] It is worth mentioning that in this embodiment, the first coupler 250 is disposed between the incident port 220 and the beam splitting module 230. Thus, when each SOA310 is sequentially coupled to the corresponding output port 240 of the beam splitting chip 200, the optical path coupling can be monitored based on the first light-receiving element 260 corresponding to the same first coupler 250. This helps to reduce the number of first couplers 250 and first light-receiving elements 260, and simplifies the device layout of the beam splitting chip 200. However, it should be understood that this application is not limited to this. In other embodiments of this application, the first coupler 250 can also be disposed in other positions, as long as it is located on the optical path from the incident port 220 to the output port 240. The position of the first coupler 250 on this optical path does not affect its function of monitoring the coupling between the light source module 100 and the beam splitting chip 200. In other embodiments of this application, the first coupler 250 may also be disposed between the first and second beam splitters of the beam splitting module 230, or between the beam splitting module 230 and the output port 240.

[0051] In addition, since the process of the laser beam entering the beam splitter chip 200 from the light source module 100 also involves beam coupling, it is also necessary to ensure that the laser beam is coupled into the above-mentioned incident port 220 with a high optical coupling efficiency. In this embodiment, the beam coupling process is monitored by a first coupler 250 and a second light receiving element 270.

[0052] Specifically, the first coupler 250 further includes a fourth port 254. The first coupler 250 is configured to output optical signals input via the first port 251 via the second port 252 and the fourth port 254. The second light-receiving element 270 is disposed on the cladding 210 and is used to receive the optical signals output via the fourth port 254. Thus, when a laser beam enters the beam splitter 200 via the incident port 220 and is transmitted to the first coupler 250, part of the laser beam's energy will be output from the second port 252 and transmitted downstream; part of the energy will be output from the fourth port 254 and transmitted to the second light-receiving element 270, thereby enabling monitoring of the optical coupling efficiency when the light source module 100 and the beam splitter 200 are coupled. The second light-receiving element 270 can adopt a structure similar to that of the first light-receiving element 260 described above. For example, the second light-receiving element 270 can also include a photodetector to determine the coupling status between the light source module 100 and the beam splitter chip 200 by the photocurrent output by the photodetector. When the photocurrent is at its maximum, the optical coupling efficiency between the light source module 100 and the beam splitter chip 200 is the highest.

[0053] It should be noted that in this application, the laser 110, the beam splitter 200, and the SOA 310 are all positioned and installed using a surface mount process. The optical adjustment between the beam splitter 200 and the SOA 310 to optimize their optical coupling efficiency is achieved by adjusting the position of the lens module 320. Similarly, the optical adjustment between the light source module 100 and the beam splitter 200 to optimize their optical coupling efficiency is achieved by adjusting the position of the second lens 140.

[0054] In this embodiment, the first coupler 250 is a directional coupler, and the first light-collecting element 260 and the second light-collecting element 270 are connected to different ends of the same waveguide. Specifically, the directional coupler includes a first waveguide and a second waveguide. The first waveguide is located on the optical path from the incident port 220 to the exit port 240, with one end connected to the incident port 220 and the other end connected to the first input port 231 of the beam splitting module. The end of the first waveguide closest to the incident port 220 is the first port 251, and the other end is the second port 252. The second waveguide is located outside the optical path from the incident port 220 to the exit port 240, and it is positioned opposite the first waveguide along a preset direction perpendicular to the thickness direction of the beam splitting chip 200, together forming the directional coupler. The end of the second waveguide near the first port 251 is the third port 253, to which the first light-receiving element 260 is connected; the end of the second waveguide near the second port 252 is the fourth port 254, to which the second light-receiving element 270 is connected. Thus, when the laser beam propagates along the first waveguide, a portion of the laser beam will couple into the second waveguide for transmission, and after being output through the fourth port 254, it will enter the second light-receiving element 270. Based on this, the coupling between the light source module 100 and the beam splitter chip 200 can be monitored. When the first beam propagates along the first waveguide, a portion of the first beam will couple into the second waveguide for transmission, and after being output through the third port 253, it will enter the first light-receiving element 260 for reception. Based on this, the coupling between the optical amplification module 300 and the beam splitter chip 200 can be monitored.

[0055] The above description uses the example of the first light-receiving element 260 and the second light-receiving element 270 being connected to the same waveguide. However, it should be understood that those skilled in the art can make adaptive modifications based on the above. For example, in some other embodiments of this application, the first coupler 250 is still a directional coupler, but the first light-receiving element 260 and the second light-receiving element 270 can also be connected to different waveguides. Specifically, the first coupler 250 includes a first waveguide, a second waveguide, and a third waveguide. The first waveguide is located on the optical path from the incident port 220 to the exit port 240, with one end connected to the incident port 220 and the other end connected to the first input port 231 of the beam splitter module; the end of the first waveguide closest to the incident port 220 is the aforementioned first port 251, and the other end is the second port 252. The second waveguide is entirely located outside the optical path from the input port 220 to the output port 240, and is positioned opposite the first waveguide along a predetermined direction perpendicular to the thickness direction of the beam splitter 200. The third waveguide is also entirely located outside the optical path from the input port 220 to the output port 240, and is positioned opposite the first waveguide along a predetermined direction perpendicular to the thickness direction of the beam splitter 200. The third waveguide and the second waveguide are located on opposite sides of the first waveguide. The first, second, and third waveguides together constitute a directional coupler. The end of the second waveguide closest to the first port 251 is the third port 253, to which the first light-receiving element 260 is connected. The end of the third waveguide closest to the second port 252 is the fourth port 254, to which the second light-receiving element 270 is connected. Thus, when the laser beam propagates along the first waveguide, a portion of the laser beam will couple into the third waveguide for transmission, and after being output from the fourth port 254, it will enter the second light-receiving element 270; based on this, the coupling between the light source module 100 and the beam splitter chip 200 can be monitored. When the first beam propagates along the first waveguide, a portion of the first beam will couple into the second waveguide for transmission, and after being input from the third port 253, it will enter the first light-receiving element 260 for reception; based on this, the coupling between the optical amplification module 300 and the beam splitter chip 200 can be monitored.

[0056] Preferably, to ensure that most of the energy of the laser beam (or emitted beam) flows to the output port 240 when it passes through the first coupler 250, the second port 252 should have a significantly higher coupling ratio than the fourth port 254; for example, in some embodiments, the coupling ratio of the second port 252 to the fourth port 254 can be 99:1; and in other embodiments, the coupling ratio of the second port 252 to the fourth port 254 can also be 995:5.

[0057] It is worth mentioning that the above description is based on the example of the second light receiving element 270 being connected to the first coupler 250, that is, the first coupler 250 having the function of transmitting optical signals to the first light receiving element 260 and the second light receiving element 270. However, it should be understood that this application is not limited to this. In other embodiments of this application, the second light receiving element 270 may also be coupled to receive at least part of the first beam of the laser beam in other ways.

[0058] For example, in some other embodiments of this application, the second light-receiving element 270 does not receive a portion of the energy of the first laser beam through the first coupler, but rather through another second coupler. Specifically, please refer to... Figure 3 This illustration shows a schematic diagram of a beam splitter chip 200b provided in other embodiments of this application. The beam splitter chip 200b still includes a cladding layer 210b, an incident port 220b, a beam splitting module 230b, an exit port 240b, a first coupler 250b, a first light-receiving element 260b, and a second light-receiving element 270b. The beam splitter chip 200b and... Figure 1 The main difference shown in the diagram is that, in this embodiment, the beam splitter 200b further includes a second coupler 280b; the first light receiving element 260b is connected to the first coupler 250b, and the second light receiving element 270 is connected to the second coupler 280b.

[0059] Specifically, the second coupler 280b is disposed on the cladding 210b and located in the optical path from the input port 220b to the output port 240b, and includes a fifth port 281b, a sixth port 282b, and a seventh port 283b. The fifth port 281b and the sixth port 282b are both located in the optical path from the output port 240b to the input port 220b. Along the transmission direction of the laser beam from the input port 220b to the output port 240b, the fifth port 281b is located upstream of the sixth port 282b; the seventh port 283b is located outside the optical path from the output port 240b to the input port 220b. The second coupler 280b is configured to output the optical signal input via the fifth port 281b via the sixth port 282b and the seventh port 283b. The second receiving element 270b is connected to the seventh port 283b and is used to receive the optical signal output via the seventh port 283b. Thus, when the light source module is coupled to the beam splitter 200b, the laser beam will enter the beam splitter 200b for transmission via the incident port 220b. When the laser beam is transmitted to the second coupler 280b, part of its energy will be output from the sixth port 282b and further flow to the output port 240b, while part of its energy will be output from the seventh port 283b and further transmitted to the second receiving element 270b connected to the seventh port 283b. The specific structure of the second coupler 280b can refer to the first coupler 250b described above; for example, it can be a directional coupler, which will not be elaborated here.

[0060] Regarding the placement of the second coupler 280b, in this embodiment, along the direction of laser beam transmission from the incident port 220b to the exit port 240b, both the first coupler 250b and the second coupler 280b are located between the incident port 220b and the beam splitting module 230b, with the second coupler 280b located upstream of the first coupler 250b. This arrangement ensures that the laser beam undergoes only one coupling during its entry into the second receiving element 270b, thereby guaranteeing that the second receiving element 270b can receive higher energy without changing the coupling ratio of each port of the second coupler 280b, thus facilitating monitoring. Meanwhile, the beam coupling process between the beam splitter chip 200b and multiple SOAs in the optical amplification module 300b can be monitored using only a single first coupler 250b. Furthermore, since the first beam may need to cross the beam splitter multiple times from the output port 240b to the first coupler 250b, and each crossing incurs losses, placing the first coupler 250b between the second coupler 280b and the beam splitter module 230b avoids the first beam needing to cross the second coupler 280b additionally. This reduces losses when the first beam reaches the first receiving element 260b, ensuring that the first receiving element 260 receives higher energy without changing the coupling ratio at each port of the first coupler 250b, thus facilitating monitoring. Of course, in other embodiments of this application, the second coupler 280b can also be located in other positions. The location of the second coupler 280b does not affect its function, and this application does not specifically limit the location of the second coupler 280b.

[0061] Regarding the beam splitter chip, it is worth mentioning that even though the above embodiments are all described using the example of the beam splitter chip including a second light-receiving element that is different from the first light-receiving element to monitor the coupling between the light source module and the beam splitter chip, this application is not limited to this. In other embodiments of this application, the first light-receiving element can also be used to monitor the coupling between the beam splitter chip and the optical amplification module.

[0062] For example, please see Figure 4 This illustration shows a schematic diagram of a beam splitter chip 200c provided in other embodiments of this application. The beam splitter chip 200c still includes a cladding layer 210c, an incident port 220c, a beam splitting module 230c, an exit port 240c, a first coupler 250c, and a first light-receiving element 260c. The beam splitter chip 200c and... Figure 1 The main difference shown in the diagram is that the beam splitter 200c does not include a second light-receiving element 270, but instead includes a beam combiner 261c disposed on the cladding 210c.

[0063] Specifically, the beam combiner 261c includes a second input terminal, a third input terminal, and a second output terminal. The second and third input terminals are the input terminals of the beam combiner 261, and the second output terminal is the output terminal of the beam combiner 261. That is, the beam combiner 261 is configured to output optical signals input via the second and / or third input terminals via the second output terminal. The second input terminal is connected to the third port of the first coupler 250c, and the third input terminal is connected to the fourth port of the first coupler 250c. The first light-receiving element 260c is connected to the second output terminal and is used to receive the optical signals output via the second output terminal. Thus, when coupling the light source module and the beam splitter 200c, the laser beam enters the beam splitter 200c through the incident port 220c and is transmitted to the first coupler 250c. Most of the laser beam's energy is output from the second port and transmitted downstream, while a small portion is output from the fourth port and further transmitted to the beam combiner 261c and the first receiving element 260c. Therefore, the optical coupling efficiency when coupling the light source module and the beam splitter 200c can be monitored through the first receiving element 260c. When coupling the beam splitter 200c with the optical amplification module, the spontaneous emission of laser light from the SOA can be utilized to control the SOA's laser emission. The laser emitted by the SOA includes the first beam emitted from the receiving end of the SOA towards the beam splitter 200c. The first beam is transmitted via the lens module to the output port 240c of the beam splitter 200c, and then further enters the beam splitter 200c for transmission via the output port 240c. When the first beam is transmitted to the first coupler 250c, part of its energy will be output from the first port, and part of its energy will be output from the third port, and then further transmitted to the beam combiner 261c and the first light-receiving element 260c. Therefore, the optical coupling efficiency when the light source module and the beam splitter 200c are coupled can be monitored through the first light-receiving element 260c.

[0064] and Figure 1 and Figure 3 Compared to the embodiments shown, in this embodiment, the beam splitter 200c is connected to the first light receiving element 260c via the first coupler 250c. This enables the monitoring of the coupling between the light source module and the beam splitter 200c, as well as the monitoring of the coupling between the beam splitter 200c and the optical amplification module. This helps to reduce the number of couplers and light receiving elements and simplify the overall architecture of the beam splitter.

[0065] For example, please see Figure 5 This illustration shows a schematic diagram of a beam splitter chip 200d provided in other embodiments of this application. The beam splitter chip 200d still includes a cladding layer 210d, an incident port 220d, a beam splitting module 230d, an exit port 240d, a first coupler 250d, and a first light-receiving element 260d. The beam splitter chip 200d and... Figure 3The main difference shown in the diagram is that the beam splitter 200d does not include a second light-receiving element, but instead includes a beam combiner 261d disposed on the cladding 210d.

[0066] Specifically, the beam combiner 261d includes a second input terminal, a third input terminal, and a second output terminal. The second and third input terminals are the input terminals of the beam combiner 261d, and the second output terminal is the output terminal of the beam combiner 261, meaning that the beam combiner 261 is configured to output optical signals input via the second and / or third input terminals via the second output terminal. The second input terminal is connected to the third port 253d of the first coupler 250d, and the third input terminal is connected to the seventh port of the second coupler 280d. The first light-receiving element 260d is connected to the second output terminal and is used to receive the optical signals output via the second output terminal. Thus, when coupling the light source module and the beam splitter 200d, the laser beam enters the beam splitter 200d through the incident port 220d and is transmitted to the second coupler 280d. Most of the laser beam's energy is output from the sixth port and transmitted downstream, while a small portion is output from the seventh port and further transmitted to the beam combiner 261d and the first receiving element 260d. Therefore, the optical coupling efficiency when coupling the light source module and the beam splitter 200d can be monitored through the first receiving element 260d. When coupling the beam splitter 200d and the optical amplification module, the spontaneous emission of laser light from the SOA can be utilized to control the SOA's laser emission. The laser emitted by the SOA includes the first beam emitted from the receiving end of the SOA towards the beam splitter 200d. The first beam is transmitted via the lens module to the output port 240d of the beam splitter 200d, and further transmitted into the beam splitter 200d via the output port 240d. When the first beam is transmitted to the second port 252d of the first coupler 250d, part of its energy will be output from the first port 251d and part of its energy will be output from the third port 253d, and further transmitted to the beam combiner 261d and the first light-receiving element 260d. Therefore, the optical coupling efficiency when the light source module and the beam splitter 200d are coupled can be monitored through the first light-receiving element 260d.

[0067] and Figure 3 Compared to the embodiment shown, in this embodiment, the beam-splitting chip 200d is connected to the first light-receiving element 260d via the second coupler 280d, which allows for monitoring of the coupling between the light source module and the beam-splitting chip 200d; although compared to... Figure 2 The embodiment adds a beam combiner 261, but the beam combiner 261 is a passive device, so it still helps to simplify the overall architecture of the beam splitter 200d, and at the same time can reduce the device cost of the beam splitter 200d.

[0068] In summary, the light source module 1 provided in this application embodiment includes a light source module 100, a beam splitter chip 200 (200b, 200c, 200d), and an optical amplification module 300. The beam splitter chip 200 includes a cladding layer 210, an incident port 220, multiple exit ports 240, a first coupler 250, and a first light-receiving element 260. The first coupler 250 is disposed on the optical path from the incident port 220 to the exit port 240, and includes a first port 251, a second port 252, and a third port 253. Both the first port 251 and the second port 252 are located on the optical path from the incident port 220 to the exit port 240. The first coupler 250 is configured to output optical signals input via the second port 252 via the first port 251 and the third port 253. The first light-receiving element 260 is connected to the third port 253 to receive optical signals output via the third port 253.

[0069] Thus, when coupling the beam splitter 200 and the optical amplification module 300, the SOA 310 in the optical amplification module 300 can radiate laser light. The laser light radiated by the SOA 310 includes a first beam emitted from the receiving end of the SOA 310 towards the beam splitter 200. The first beam enters the beam splitter 200 through the output port 240 for transmission. When the first beam reaches the first coupler 250, part of its energy will be output from the first port 251, and part of its energy will be output from the third port 253, and further transmitted to the first receiving element 260 connected to the third port 253. Therefore, the coupling status between the beam splitter 200 and the optical amplification module 300 can be monitored based on the optical signal energy obtained by the first receiving element 260. That is, the light source module 1 provided in this application embodiment can improve the current situation in related technologies where the optical path coupling status between the beam splitter 200 and the optical amplification module 300 cannot be monitored, which is beneficial to improving the debugging efficiency of the above-mentioned optical path coupling process.

[0070] Please see Figure 6 Based on the same inventive concept, this application also provides a lidar 2, which includes a housing 21 and a light source module 1 as described in any of the above embodiments, the light source module 1 being housed within the housing 21. The housing 21 serves as the mounting base for the remaining components of the lidar 2, and the light source module 1 is used to generate an emitted beam for detecting target objects.

[0071] Since it includes the aforementioned light source module 1, the lidar 2 can improve the current situation where the optical path coupling between the beam splitter chip and the optical amplification module in the lidar cannot be monitored, which is beneficial to improving the debugging efficiency of the aforementioned optical path coupling process.

[0072] 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" means at least two, for example, two, three, four, etc. "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.

[0073] The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Therefore, any equivalent variations made in accordance with the claims of this application shall still fall within the scope of this application.

Claims

1. A light source module, characterized in that, This includes a light source module, a beam splitter chip, and an optical amplification module; The light source module is used to generate a laser beam; The beam splitter chip includes a cladding and an incident port, a plurality of exit ports, a first coupler, and a first light-receiving element disposed on the cladding. The beam splitter chip is configured to receive the laser beam through the incident port, so that the laser beam enters the beam splitter chip and is split, and to output the emitted beam obtained by splitting the laser beam through the exit ports. The first coupler is located on the optical path from the incident port to the exit port and includes a first port, a second port, and a third port. The first port and the second port are both located on the optical path from the incident port to the exit port. Along the transmission direction of the laser beam from the incident port to the exit port, the first port is located upstream of the second port. The first coupler is configured to output an optical signal input through the second port through the first port and the third port. The first light-receiving element is used to receive the optical signal output through the third port. The optical amplification module includes multiple semiconductor optical amplifiers, each of which corresponds to one of the emission ports. The semiconductor amplifiers are used to receive and amplify the emitted light beam.

2. The light source module according to claim 1, characterized in that, The beam splitter chip includes a beam splitter module disposed in the cladding. The beam splitter module is used to split the laser beam. The beam splitter module includes a first input terminal and a plurality of first output terminals. The first input terminal is connected to the incident port and is used to receive the laser beam. The first output terminal is used to output the emitted beam obtained by the beam splitter module from the laser beam. Each of the emitted ports is connected to a first output terminal. The semiconductor optical amplifier includes an optical transmission waveguide extending along a first direction. The optical transmission waveguide includes a receiving end face and an emitting end face opposite to each other along the first direction. The receiving end face is used to receive the emitted beam, and the emitting end face is used to emit the amplified emitted beam. The direction in which the emitted beam is incident on the receiving end face is a second direction, and the second direction has a first acute angle with the normal of the receiving end face.

3. The light source module according to claim 2, characterized in that, The first coupler is located between the incident port and the beam splitter module.

4. The light source module according to claim 1, characterized in that, The first coupler also includes a fourth port, and the first coupler is configured to output an optical signal input via the first port via the second port and the fourth port; The beam splitter chip also includes a second light-receiving element disposed in the cladding, the second light-receiving element being used to receive the optical signal output via the fourth port.

5. The light source module according to claim 4, characterized in that, The first coupler is a directional coupler; The first light-receiving element and the second light-receiving element are connected to different ends of the same waveguide, or the first light-receiving element and the second light-receiving element are connected to different waveguides.

6. The light source module according to claim 1, characterized in that, The beam splitter chip also includes: A second coupler, disposed in the cladding and located on the optical path from the incident port to the exit port, includes a fifth port, a sixth port, and a seventh port. The fifth port and the sixth port are both located on the optical path from the exit port to the incident port. Along the propagation direction of the laser beam from the incident port to the exit port, the fifth port is upstream of the sixth port. The second coupler is configured to output an optical signal input via the fifth port via the sixth and seventh ports. The second light-receiving element is disposed in the cladding and is used to receive the optical signal output through the seventh port.

7. The light source module according to claim 1, characterized in that, The first coupler further includes a fourth port, and the first coupler is configured to output an optical signal input via the first port via the second port and the fourth port; The beam splitter chip also includes a beam combiner disposed on the cladding. The beam combiner includes a second input terminal, a third input terminal, and a second output terminal. The beam combiner is configured to output optical signals input via the second input terminal and / or the third input terminal via the second output terminal. The second input terminal is connected to the third port, and the third input terminal is connected to the fourth port. The first light-receiving element is used to receive the light signal output through the second output terminal.

8. The light source module according to claim 1, characterized in that, The beam splitter chip also includes: A second coupler, disposed in the cladding and located on the optical path from the incident port to the exit port, includes a fifth port, a sixth port, and a seventh port. The fifth port and the sixth port are both located on the optical path from the exit port to the incident port. Along the propagation direction of the laser beam from the incident port to the exit port, the fifth port is upstream of the sixth port. The second coupler is configured to output an optical signal input via the fifth port via the sixth and seventh ports. A beam combiner, disposed in the cladding, includes a second input terminal, a third input terminal, and a second output terminal. The beam combiner is configured to output optical signals input via the second input terminal and / or the third input terminal via the second output terminal. The second input terminal is connected to the third port, and the third input terminal is connected to the seventh port. The first light-receiving element is used to receive the light signal output through the second output terminal.

9. The light source module according to claim 4, characterized in that: The first light-receiving element includes a photodetector or a grating; The second light-receiving element includes a photodetector or a grating.

10. A lidar, characterized in that, It includes a housing and a light source module as described in any one of claims 1 to 9, wherein the light source module is housed in the housing.

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