Optical waveguide assembly and related device

Abstract

An optical waveguide assembly and a related device are applied to the technical field of laser radars. The optical waveguide assembly comprises M first coupling units and a first optical signal processing assembly, the first optical signal processing assembly is provided with M first ports and N second ports, M is an integer greater than or equal to 3, N is an integer greater than or equal to 2, and N is less than or equal to M; the first optical signal processing assembly comprises at least M-2 first phase control units and at least two power distribution units; the first phase control unit is arranged between the first coupling unit and the power distribution units, or the first phase control unit is arranged between any two of the at least two power distribution units. According to the optical waveguide assembly, the input optical signal can be transmitted to the output port according to the configured transmittance, the walk-off problem in a laser radar is solved, the received long-distance optical signal and the received short-distance optical signal can be relatively balanced, and meanwhile the number of elements needed by the optical waveguide assembly is reduced.

Description

Technical Field

[0001] This application relates to the technical field of lidar, and particularly to an optical waveguide component and related devices. Background Art

[0002] With the development of information technology and computer vision, detection technology has made rapid progress. A variety of detection devices have brought great convenience to people's lives and travel. Detection devices can be regarded as the "eyes" of equipment to sense the environment, including vision sensors such as cameras and radar sensors such as millimeter-wave radars, lidars, and ultrasonic radars. Among them, lidar (light detection and ranging, Lidar, or optical detection and ranging device) has the advantages of high resolution, good detection performance, and strong concealment, and plays an important role in the process of equipment sensing the environment. It has been widely used especially in the field of intelligent driving, contributing to the further development of intelligent driving technology. Among them, coherent lidar is a radar that uses a frequency-modulated signal light as the transmitted signal for target detection and processes the local oscillation (LO) of the transmitted signal and the returned signal of the transmitted signal to obtain relevant information about the target. The laser carrier of coherent lidar often undergoes modulation in a certain form, such that the frequency changes with time, and its pattern can be sawtooth, triangular, or sine waveforms. A lidar whose emitted beam has a linearly varying frequency is called a frequency modulated continuous wave (FMCW) lidar. It combines laser linear frequency-swept ranging technology and scanning imaging technology and has unique speed detection advantages, and is widely used in intelligent driving scenarios.

[0003] The lidar includes a transmitting end and a receiving end. Since it needs to transmit and receive laser light, a variety of optical components are also required inside to process the light beam. Especially for FMCW lidar, coherent components (such as the optical path for transmitting the LO, the mixing components for the returned signal and the LO, etc.) are needed to support coherent detection. Currently, FMCW lidar uses a combination of a fast steering mirror and a slow scanning mirror for two-dimensional beam scanning. After the silicon optical waveguide emits an optical signal, it is irradiated onto the fast steering mirror through the transmitting optical lens. After being reflected by the object to be measured, it passes through the folding mirror and the receiving optical lens and is coupled to the silicon optical chip. After the light beam is reflected by the target, due to the different distances of the objects to be measured, the delay times of the backscattered light signals at close range and at long range are different. When the scanning mirror rotates continuously, a delay angle related to the target distance will be generated. Due to the existence of the delay angle, the transmission paths of the backscattered light signals at close range and at long range before and after passing through the scanning device are no longer the same, and there is an offset relative to the position of the receiving waveguide, that is, the walk-off effect occurs, which will cause the backscattered light signal to be difficult to be coupled into the silicon optical chip through the waveguide, and further cause the loss of the backscattered light signal.

[0004] How to solve the above-mentioned walk-off problem is a hot issue being studied by those skilled in the art. Summary of the Invention

[0005] Embodiments of the present application provide an optical waveguide component and related devices, which can solve the walk-off problem in FMCW lidar.

[0006] In a first aspect, embodiments of the present application provide an optical waveguide component, which includes:

[0007] M first coupling units and a first optical signal processing component, the first optical signal processing component having M first ports and N second ports, where M is an integer greater than or equal to 3, N is an integer greater than or equal to 2, and N is less than or equal to M; wherein:

[0008] The first optical signal processing component includes at least M - 2 first phase control units and at least two power distribution units;

[0009] The first phase control unit is disposed between the first coupling unit and the power distribution unit, or the first phase control unit is disposed between any two of the at least two power distribution units.

[0010] In embodiments of the present application, an optical waveguide component is provided, which includes M first coupling units and a first optical signal processing component. The M first coupling units and the first optical signal processing component can be a chip-based component with high-density integration, which can reduce the overall volume of the optical waveguide component system.

[0011] Among them, the M first coupling units are used to couple the optical signal in the spatial optical field to the first optical signal processing component, or, alternatively, to couple the optical signal output by the first optical signal processing component to the spatial optical field. Therefore, the optical waveguide component in the embodiment of the present application is applicable to both signal receiving scenarios and signal sending scenarios, and the embodiment of the present application does not limit this. The first optical signal processing component has M first ports and N second ports, and through the internal structure of the component, M-channel signal input and N-channel signal output can be achieved, or alternatively, N-channel signal input and M-channel signal output can also be achieved. Specifically, the first optical signal processing component can transmit the input optical signal to the output port according to any configured transmittance through at least two power distribution units inside. It can be understood that when there is only one first port and one second port with signal input or output, the configured transmittance is a value. When there are M first ports and N second ports with signal input or output, the configured transmittance includes M×N values. Transmitting according to any configured transmittance can be understood as pre-configuring the required transmittance according to any application scenario, or it can also be understood as adjusting the configured transmittance in real time according to the changing requirements of the application scenario during transmission. The present application does not limit this. At least M-2 first phase control units in the first optical signal processing component are used to adjust the phase of the transmitted optical signal, so that after the nth second port satisfies the phase matching condition, the energy of the output optical signal can be expressed as T = P1×S1n + P2×S2n + … + Pm×Smn, where S1n, S2n, …, Smn respectively represent the transmittances corresponding to the optical signals input from the first first port to the mth first port output from the nth second port, and P1, P2, …, Pm respectively represent the powers of the optical signals input from the first first port to the mth first port. It can be seen that through the cooperation of at least M-2 first phase control units and at least two power distribution units, the energy of the optical signal output from the nth second port corresponding to the optical signal input from any first port can be relatively balanced, that is, P1×S1n, P2×S2n, …, Pm×Smn are relatively balanced, so as to achieve that no matter how the position of the backscattered optical signal corresponding to the long-distance target changes, a certain intensity of backscattered optical signal can always be received and output. Optionally, the first phase control unit can be arranged between the first coupling unit and the power distribution unit, or can also be arranged between any two of at least two power distribution units. The present application does not limit this.

[0012] At present, after the outgoing light beam from the laser radar transmitter is reflected by the target, the delay time of the short-range echo light signal and the long-range echo light signal is different due to the different distances of the target to be measured. When the scanning mirror continues to rotate, a delay angle related to the target distance will be generated. Due to the existence of the delay angle, the transmission paths of the short-range echo light signal and the long-range echo light signal are no longer consistent before and after passing through the scanning device, and they are offset relative to the receiving waveguide position, which produces a walk-off effect. This makes it difficult for the echo light signal to be coupled to the silicon photonic chip through the waveguide, which in turn causes the echo light signal to be lost.

[0013] In the embodiment of the present application, the long-distance echo optical signal can be received by M first coupling units and transmitted to the first optical signal processing component, the first phase control unit in the first optical signal processing component adjusts the phase thereof, and the power distribution unit in the first optical signal processing component transmits the input long-distance echo optical signal to the output port according to the configured transmittance, so that the loss of the echo optical signal corresponding to the long-distance target is smaller, while the loss of the echo optical signal corresponding to the close-range target is larger, thereby achieving that no matter how the position of the echo optical signal corresponding to the long-distance target walks away, an echo optical signal of a certain intensity can always be received and output, thereby solving the walk-away problem in the FMCW laser radar, and achieving relative balance between the received echo optical signal corresponding to the long-distance target and the echo optical signal corresponding to the close-range target, while reducing the number of components required for the optical waveguide component.

[0014] In a possible implementation, the optical waveguide component is an optical signal receiving component, the M first ports are used to receive optical signals, and the first optical signal processing component processes the optical signals received by the M first ports so that the corresponding transmittance increases along the first direction.

[0015] In an embodiment of the present application, a possible specific embodiment of an optical waveguide component as an optical signal receiving component is provided. Specifically, when the optical waveguide component is an optical signal receiving component, M first ports are used to receive optical signals, and the nth port among the N second ports is used to output the optical signal after being processed by the first optical signal processing component. Among them, the transmittance corresponding to the optical signal received by the M first ports after being processed by the first optical signal processing component increases along the first direction. Optionally, the first direction may be the direction in which the optical signal travels away. For example, the increase in the transmittance along the first direction can be expressed as S1n≤S2n≤……≤Smn, where 1, 2, ……, m are the port numbers corresponding to the M first ports arranged in sequence from receiving the far-distance echo optical signal to receiving the near-distance echo optical signal, m is a positive integer less than or equal to M, n is any port number among the N second ports, n is a positive integer less than or equal to N, and Smn represents the transmittance corresponding to the optical signal received by the mth first port and output from the nth second port after being processed. It can be understood that receiving, processing, and outputting optical signals according to the transmittance in the embodiment of the present application can make the loss of the echo optical signal corresponding to the far-distance target smaller, while the loss of the echo optical signal corresponding to the near-distance target larger, so as to achieve that no matter how the position of the echo optical signal corresponding to the far-distance target changes, an echo optical signal with a certain intensity can always be received and output and output at the nth second port. At this time, the output port can achieve relatively balanced reception of the echo optical signal corresponding to the far-distance target and the echo optical signal corresponding to the near-distance target, and at the same time reduce the number of components required for the optical waveguide component.

[0016] In a possible embodiment, the optical waveguide component is an optical signal transmitting component, the M first ports are used to transmit optical signals, and the transmittance corresponding to the optical signals transmitted by the M first ports after being processed by the first optical signal processing component increases along the second direction.

[0017] In an embodiment of the present application, a possible specific implementation of an optical waveguide component as an optical signal transmitting component is provided. Specifically, when the optical waveguide component is an optical signal transmitting component, the nth second port among the N second ports is used to receive an optical signal, and the M first ports are used to output the optical signal after being processed by the first optical signal processing component. Among them, the transmittance corresponding to the optical signal transmitted by the M first ports after being processed by the first optical signal processing component increases along the second direction. Optionally, the second direction may be the direction in which the optical signal travels away. For example, the increase in the transmittance along the second direction can be expressed as Sn1≤Sn2≤……≤Snm, where n is the port number of one of the N second ports that receives the optical signal, n is a positive integer less than or equal to N, 1, 2, ……, m are the port numbers corresponding to the M first ports arranged in sequence from transmitting a long-distance optical signal to transmitting a short-distance optical signal, m is a positive integer less than or equal to M, and Snm represents the transmittance corresponding to the optical signal received by the nth second port and output from the mth first port after being processed. It can be understood that receiving, processing, and outputting the optical signal according to the transmittance in the embodiment of the present application can make the loss of the echo optical signal corresponding to the long-distance target smaller, while the loss of the echo optical signal corresponding to the short-distance target larger. Thus, no matter how the position of the echo optical signal corresponding to the long-distance target travels away, an echo optical signal with a certain intensity can always be received and output, and the echo optical signal corresponding to the received long-distance target and the echo optical signal corresponding to the short-distance target can be relatively balanced. As a result, the echo signals from both short-distance and long-distance targets can be received simultaneously at an output end, reducing the dynamic range requirement of the subsequent trans-impedance amplifier (TIA). Compared with the method of using multiple waveguides to receive the departing light spot respectively, the embodiment of the present application can reduce the number of components required for the receiving system.

[0018] In a possible implementation manner, the sum s1 of the M transmittances corresponding to the optical signals received by the M first ports after being processed by the first optical signal processing component satisfies the following condition: 0.9≤s1≤1.

[0019] In an embodiment of the present application, a possible specific embodiment of an optical waveguide component as an optical signal receiving component is provided. Specifically, when the optical waveguide component is an optical signal receiving component, M first ports are used to receive optical signals, and the nth second port among the N second ports is used to output the optical signal after being processed by the first optical signal processing component. Among them, the sum s1 of the M transmittances corresponding to the optical signals received by the M first ports after being processed by the first optical signal processing component is within the range of [0.9, 1]. For example, the increase of the above M transmittances along the direction in which the optical signal travels away can be expressed as S1n ≤ S2n ≤... ≤ Smn, where 1, 2,..., m are the port numbers corresponding to the M first ports arranged in sequence from receiving the far-distance echo optical signal to receiving the near-distance echo optical signal, m is a positive integer less than or equal to M, n is one of the port numbers of the N second ports, n is a positive integer less than or equal to N, and Smn represents the transmittance corresponding to the optical signal received by the mth first port and output from the nth second port after being processed. Then, s1 = S1n + S2n +... + Smn is within the range of [0.9, 1], that is

[0020] In a possible embodiment, the sum s2 of the M transmittances corresponding to the optical signals sent by the M first ports after being processed by the first optical signal processing component satisfies the following condition: 0.9 ≤ s2 ≤ 1.

[0021] In an embodiment of the present application, a possible specific embodiment of an optical waveguide component as an optical signal transmitting component is provided. Specifically, when the optical waveguide component is an optical signal transmitting component, the nth second port among the N second ports is used to receive an optical signal, and M first ports are used to output the optical signal after being processed by the first optical signal processing component. Among them, the sum s2 of the M transmittances corresponding to the optical signals sent by the M first ports after being processed by the first optical signal processing component is within the range of [0.9, 1]. For example, the increase of the above M transmittances along the direction in which the optical signal travels away can be expressed as Sn1 ≤ Sn2 ≤... ≤ Snm, where n is one of the port numbers of the N second ports that receives the optical signal, n is a positive integer less than or equal to N, 1, 2,..., m are the port numbers corresponding to the M first ports arranged in sequence from sending the far-distance optical signal to sending the near-distance optical signal, m is a positive integer less than or equal to M, and Snm represents the transmittance corresponding to the optical signal received by the nth second port and output from the mth first port after being processed. Then, s2 = Sn1 + Sn2 +... + Snm is within the range of [0.9, 1], that is

[0022] In a possible embodiment, the first phase control unit is disposed between the first coupling unit and the power distribution unit and includes:

[0023] The at least M-2 first phase control units are cascade-connected to the M first coupling units.

[0024] In an embodiment of the present application, a possible specific implementation manner of setting the first phase control units is provided. Specifically, at least M-2 first phase control units are cascade-connected to M first coupling units. Optionally, when the number of first phase control units is M, the M first phase control units are respectively connected to the M first coupling units in one-to-one correspondence. Optionally, when the number of first phase control units is less than M, the at least M-2 first phase control units are respectively connected to one first coupling unit, and the other first coupling units not connected to the first phase control units are directly connected to the above power distribution unit. Optionally, when the number of first phase control units is more than M, the M first coupling units are respectively connected to the M first phase control units in one-to-one correspondence, and in addition, the redundant first phase control units are respectively connected to some first coupling units. The first phase control units provided in the embodiments of the present application can be used to adjust the phase of the transmitted optical signal so as to meet the phase matching condition, and further ensure that when receiving the echo signal, coherent superposition is performed according to the preset transmittance, reducing energy loss.

[0025] In a possible implementation manner, the number of layers x formed by cascade-connecting the at least two power distribution units satisfies the following condition: p ≤ x ≤ q;

[0026] wherein, x is an integer greater than 1, q is an integer greater than 1 and satisfies the following condition: q = M-1, and p is an integer greater than 1 and satisfies the following condition: 2 p-1 <M≤2 p .

[0027] In an embodiment of the present application, a possible specific implementation manner of setting at least two power distribution units is provided. Specifically, the number of layers x formed after cascade-connecting the at least two power distribution units satisfies p ≤ x ≤ q, which can achieve transmitting the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide component.

[0028] Optionally, when the first optical signal processing component has M = 3 first ports, p = 2, q = 2, and the number of layers x formed by cascade-connecting the at least two power distribution units is x = 2.

[0029] Optionally, when the first optical signal processing component has M = 4 first ports, p = 2, q = 3, and the number of layers x formed by cascade-connecting the at least two power distribution units is x = 2 or 3.

[0030] Optionally, when the first optical signal processing component has M = 5 first ports, p = 3, q = 4, and the number of cascaded layers x formed by cascading at least two power distribution units is 3 or 4.

[0031] Optionally, when the first optical signal processing component has M = 6 first ports, p = 3, q = 5, and the number of cascaded layers x formed by cascading at least two power distribution units is 3 or 4 or 5.

[0032] Optionally, when the first optical signal processing component has M = 7 first ports, p = 3, q = 6, and the number of cascaded layers x formed by cascading at least two power distribution units is 3 or 4 or 5 or 6.

[0033] Optionally, when the first optical signal processing component has M = 8 first ports, p = 3, q = 7, and the number of cascaded layers x formed by cascading at least two power distribution units is 3 or 4 or 5 or 6 or 7.

[0034] In a possible implementation manner, the power distribution unit includes at least one of the following:

[0035] Directional coupler, multimode interferometer, star coupler, tunable ratio coupler, Y-branch splitter.

[0036] In the embodiments of the present application, several possible specific implementation manners of the power distribution unit are provided. Specifically, the above power distribution unit may include at least one of a directional coupler, a multimode interferometer, a star coupler, a tunable ratio coupler, and a Y-branch splitter. Through the power distribution unit in the embodiments of the present application, the input optical signal can be transmitted to the output port according to any configured transmittance, the walk-off problem in the FMCW lidar is solved, and at the same time, the number of components required for the optical waveguide component is reduced.

[0037] In a possible implementation manner, the at least two power distribution units include: a first 2×2 directional coupler, a first 1×2 multimode interferometer, and a second 1×2 multimode interferometer;

[0038] Wherein, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascaded with the first 1×2 multimode interferometer and the second 1×2 multimode interferometer in sequence.

[0039] In an embodiment of the present application, a possible specific embodiment of at least two power distribution units is provided. Specifically, the at least two power distribution units include a first 2×2 directional coupler, a first 1×2 multimode interferometer, and a second 1×2 multimode interferometer. By cascading the above three components, it is possible to transmit the input optical signal to the output port with any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide assembly.

[0040] In a possible embodiment, the at least two power distribution units include: a first 2×2 directional coupler, a second 2×2 directional coupler, and a first 1×2 multimode interferometer;

[0041] Wherein, one port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other port of the first 2×2 directional coupler is cascaded with the second 2×2 directional coupler and the first 1×2 multimode interferometer in sequence.

[0042] In an embodiment of the present application, a possible specific embodiment of at least two power distribution units is provided. Specifically, the at least two power distribution units include a first 2×2 directional coupler, a second 2×2 directional coupler, and a first 1×2 multimode interferometer. By cascading the above three components, it is possible to transmit the input optical signal to the output port with any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide assembly.

[0043] In a possible embodiment, the at least two power distribution units include: a first 2×2 directional coupler, a second 2×2 directional coupler, and a third 2×2 directional coupler;

[0044] Wherein, one port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other port of the first 2×2 directional coupler is cascaded with the second 2×2 directional coupler and the third 2×2 directional coupler in sequence;

[0045] Alternatively, one port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, one port of the second 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other ports of the first 2×2 directional coupler and the second 2×2 directional coupler are respectively cascaded with the third 2×2 directional coupler.

[0046] In an embodiment of the present application, a possible specific embodiment of at least two power distribution units is provided. Specifically, the at least two power distribution units include a first 2×2 directional coupler, a second 2×2 directional coupler, and a third 2×2 directional coupler. By cascading the above three components, it is possible to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide assembly.

[0047] In a possible embodiment, the at least two power distribution units include: a first 2×2 directional coupler, a first 1×2 multimode interferometer, a second 1×2 multimode interferometer, and a third 1×2 multimode interferometer;

[0048] Wherein, one port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other port of the first 2×2 directional coupler is cascaded with the first 1×2 multimode interferometer, the second 1×2 multimode interferometer, and the third 1×2 multimode interferometer in sequence.

[0049] In an embodiment of the present application, a possible specific embodiment of at least two power distribution units is provided. Specifically, the at least two power distribution units include a first 2×2 directional coupler, a first 1×2 multimode interferometer, a second 1×2 multimode interferometer, and a third 1×2 multimode interferometer. By cascading the above four components, it is possible to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide assembly.

[0050] In a possible embodiment, the at least two power distribution units include: a first adjustable ratio coupler, a second adjustable ratio coupler, and a third adjustable ratio coupler, and the coupling ratio configured by the adjustable ratio coupler is any value;

[0051] Wherein, one port of the first adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, and the other port of the first adjustable ratio coupler is cascaded with the second adjustable ratio coupler and the third adjustable ratio coupler in sequence;

[0052] Alternatively, one port of the first adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, one port of the second adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, and the other ports of the first adjustable ratio coupler and the second adjustable ratio coupler are respectively cascaded with the third adjustable ratio coupler.

[0053] In an embodiment of the present application, a possible specific embodiment of at least two power distribution units is provided. Specifically, the at least two power distribution units include a first adjustable ratio coupler, a second adjustable ratio coupler, and a third adjustable ratio coupler. By cascading the above three components, it is possible to transmit the input optical signal to the output port with any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide assembly.

[0054] In a possible embodiment, the adjustable ratio coupler includes at least one of the following:

[0055] Two 2×2 directional couplers and an adjustable phase control unit, and the one adjustable phase control unit is disposed between the two 2×2 directional couplers;

[0056] Or, one 2×2 directional coupler, one adjustable phase control unit, and one 2×2 multimode interferometer, and the one adjustable phase control unit is disposed between the one 2×2 directional coupler and the one 2×2 multimode interferometer;

[0057] Or, one 2×2 directional coupler, one adjustable phase control unit, and one 2×1 multimode interferometer, and the one adjustable phase control unit is disposed between the one 2×2 directional coupler and the one 2×1 multimode interferometer.

[0058] In an embodiment of the present application, several possible specific embodiments of the adjustable ratio coupler are provided. Specifically, the adjustable ratio coupler may include the above-mentioned various components and their corresponding connection relationships, so that the required transmittance can be configured in advance according to any application scenario, or the configured transmittance can be adjusted in real time according to the changing requirements of the application scenario during transmission, so as to transmit the input optical signal to the output port with any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide assembly.

[0059] In a possible embodiment, the at least two power distribution units include: at least one phase control unit, a first multimode interferometer having M input ports and M output ports, and a second multimode interferometer having N input ports and N output ports;

[0060] Wherein, one side port of the first multimode interferometer is connected to a first coupling unit or a first phase control unit, and the other side port of the first multimode interferometer is cascaded with the at least one phase control unit and the second multimode interferometer in sequence.

[0061] In an embodiment of the present application, a possible specific embodiment of at least two power distribution units is provided. Specifically, the at least two power distribution units include at least one phase control unit, a first multimode interferometer with M input ports and M output ports, and a second multimode interferometer with N input ports and N output ports. By cascading the above at least three components, it is possible to transmit the input optical signal to the output port with any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide component.

[0062] In a possible embodiment, the at least two power distribution units include: at least one phase control unit, a first star coupler with M input ports and M output ports, and a second star coupler with N input ports and N output ports;

[0063] Wherein, one side port of the first star coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first star coupler is cascaded with the at least one phase control unit and the second star coupler in sequence.

[0064] In an embodiment of the present application, a possible specific embodiment of at least two power distribution units is provided. Specifically, the at least two power distribution units include at least one phase control unit, a first star coupler with M input ports and M output ports, and a second star coupler with N input ports and N output ports. By cascading the above at least three components, it is possible to transmit the input optical signal to the output port with any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide component.

[0065] In a possible embodiment, the optical waveguide component further includes:

[0066] A monitoring unit;

[0067] The monitoring unit is configured to monitor the power of the optical signal in the first optical path from the spatial light field.

[0068] In an embodiment of the present application, a possible specific embodiment of an optical waveguide assembly is provided. Specifically, the optical waveguide assembly further includes a monitoring unit, which is used to monitor the power of the optical signal in the first optical path from the spatial light field. It can be understood that the monitoring unit is applicable to the signal receiving scenario, which is beneficial to the installation and adjustment of the radar system to which the optical waveguide assembly is applied. During the assembly of the optical components, it is necessary to couple the optical signal into the receiving component under static conditions (without a scanner). By setting the monitoring unit, the static spot position can be quickly aligned with the coupling unit. Therefore, the monitoring unit can monitor the working state of the receiving component under static conditions and can be used for the self-check of the lidar system.

[0069] In a possible embodiment, the monitoring unit is connected to the first output port of the first optical signal processing component, and the first optical path is the optical path in which the near-field echo optical signal from the spatial light field passes through the first coupling unit and the first optical signal processing component in sequence and is output from the first output port of the first optical signal processing component.

[0070] In an embodiment of the present application, a possible specific embodiment of setting the monitoring unit is provided. Specifically, the monitoring unit is connected to the first output port of the first optical signal processing component. In this case, the first optical path monitored by the monitoring unit is the optical path in which the near-field echo optical signal from the spatial light field passes through the first coupling unit and the first optical signal processing component in sequence and is output from the first output port of the first optical signal processing component. Optionally, the first output port may be a port with input / output (I / O) function. Through the embodiments of the present application, one of the N second ports of the first optical signal processing component can be borrowed as the first output port for connection with the monitoring unit to achieve the installation and adjustment of the radar system to which the optical waveguide assembly is applied.

[0071] In a possible embodiment, the monitoring unit is connected to the second output port, and the first optical path is the optical path in which the near-field echo optical signal from the spatial light field passes through the first coupling unit and is output from the second output port.

[0072] In an embodiment of the present application, a possible specific embodiment of setting a monitoring unit is provided. Specifically, the monitoring unit is connected to the second output port. In this case, the first optical path monitored by the monitoring unit is the optical path output from the second output port after the near-field echo optical signal from the spatial optical field passes through the first coupling unit. Optionally, the second output port may be a port with input / output (I / O) function. Through the embodiments of the present application, instead of occupying the N second ports of the first optical signal processing component, a path of optical signal coupled by a single first coupling unit can be used as the second output port to be connected to the monitoring unit, so as to realize the alignment of the radar system applied by the optical waveguide component.

[0073] In a second aspect, an embodiment of the present application provides a transceiver device, which includes at least two optical waveguide components as described in the first aspect and any possible embodiments thereof above, and the at least two optical waveguide components are arranged off-axis or coaxially.

[0074] Through the embodiments of the present application, a transceiver device is provided. The transceiver device includes at least two optical waveguide components as described in the first aspect and any possible embodiments thereof above, and the at least two optical waveguide components are arranged off-axis or coaxially. It can be understood that the at least two optical waveguide components included in the transceiver device in the embodiments of the present application are applicable to both signal reception scenarios and signal transmission scenarios, and the embodiments of the present application do not limit this. Through the waveguide device in the embodiments of the present application, the input far-field echo optical signal can be transmitted to the output port according to the configured transmittance, so that the echo optical signal corresponding to the far-field target has less loss, while the echo optical signal corresponding to the near-field target has greater loss. Thus, no matter how the position of the echo optical signal corresponding to the far-field target deviates, an echo optical signal with a certain intensity can always be received and output, solving the deviation problem in FMCW lidar, and the echo optical signal corresponding to the received far-field target and the echo optical signal corresponding to the near-field target can be relatively balanced, while reducing the number of components required for the optical waveguide component.

[0075] In a third aspect, an embodiment of the present application provides a chip, which includes the optical waveguide component as described in the first aspect or any possible embodiments of the first aspect above, or includes the transceiver device as described in the second aspect.

[0076] In a fourth aspect, an embodiment of the present application provides a radar or a radar system, which includes the optical waveguide component as described in the first aspect or any possible embodiments of the first aspect above, or includes the transceiver device as described in the second aspect, or includes the chip as described in the third aspect.

[0077] In a possible implementation, the radar includes, but is not limited to, lidar, etc.

[0078] In a possible implementation, there may be intelligent sensors integrating multiple sensors. When the above intelligent sensors include, but are not limited to, laser detection functions, etc., the above intelligent sensors can also be referred to as radars or radar systems.

[0079] In a fifth aspect, an embodiment of the present application provides a terminal device, which includes the optical waveguide component described in the first aspect or any possible implementation of the first aspect above, or includes the transceiver device described in the second aspect above, or includes the chip described in the third aspect above, or includes the radar or radar system described in the fourth aspect above.

[0080] In a sixth aspect, an embodiment of the present application provides a vehicle end, which includes the optical waveguide component described in the first aspect or any possible implementation of the first aspect above, or includes the transceiver device described in the second aspect above, or includes the chip described in the third aspect above, or includes the radar or radar system described in the fourth aspect above, or includes the terminal device described in the fifth aspect above.

[0081] The embodiments of the present application can transmit the input long-distance return optical signal to the output port according to the configured transmittance, so that the return optical signal corresponding to the long-distance target has less loss, while the return optical signal corresponding to the short-distance target has greater loss. Thus, no matter how the position of the return optical signal corresponding to the long-distance target moves away, a return optical signal with a certain intensity can always be received and output, solving the walk-off problem in FMCW lidar, and can achieve relatively balanced return optical signals corresponding to long-distance targets and short-distance targets received, while reducing the number of components required for the optical waveguide component. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0083] Figure 1A FIG. is a schematic diagram of an application scenario of a radar provided by an embodiment of the present application;

[0084] Figure 1B FIG. is a schematic diagram of an application scenario of a radar provided by an embodiment of the present application;

[0085] Figure 2A FIG. is a schematic diagram of the architecture of a radar provided by an embodiment of the present application;

[0086] Figure 2B A schematic diagram of the architecture of a radar provided by an embodiment of the present application;

[0087] Figure 3 A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0088] Figure 4A A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0089] Figure 4B A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0090] Figure 4C A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0091] Figure 4D A schematic diagram of the application scenario of an optical waveguide component provided by an embodiment of the present application;

[0092] Figure 5A A schematic cross-sectional view of an optical waveguide provided by an embodiment of the present application;

[0093] Figure 5B Another schematic cross-sectional view of an optical waveguide provided by an embodiment of the present application;

[0094] Figure 6 A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0095] Figure 7 A schematic diagram of the structure of a directional coupler provided by an embodiment of the present application;

[0096] Figure 8 A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0097] Figure 9 A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0098] Figure 10 A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0099] Figure 11 A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0100] Figure 12 A schematic diagram of the structure of an optical waveguide component provided by an embodiment of the present application;

[0101] Figure 13Schematic diagram of a optical waveguide component provided by an embodiment of the present application;

[0102] Figure 14 Schematic diagram of a tunable proportional coupler provided by an embodiment of the present application;

[0103] Figure 15 Schematic diagram of a optical waveguide component provided by an embodiment of the present application;

[0104] Figure 16A Schematic diagram of a transceiver device provided by an embodiment of the present application;

[0105] Figure 16B Schematic diagram of a transceiver device provided by an embodiment of the present application;

[0106] Figure 17A Schematic diagram of a transceiver device provided by an embodiment of the present application;

[0107] Figure 17B Schematic diagram of a transceiver device provided by an embodiment of the present application;

[0108] Figure 17C Schematic diagram of a transceiver device provided by an embodiment of the present application;

[0109] Figure 18 Schematic diagram of the architecture of a radar provided by an embodiment of the present application. Detailed implementation manners

[0110] In order to make the objectives, technical solutions and advantages of the present application clearer, the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.

[0111] The terms "first" and "second" etc. in the specification, claims and drawings of the present application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device etc. that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices etc.

[0112] As used herein, "embodiment" means that the specific features, structures, or characteristics described in connection with an embodiment can be included in at least one embodiment of the present application. The phrase may not necessarily refer to the same embodiment at various positions in the specification, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art can explicitly and implicitly understand that in the various embodiments of the present application, if there is no special description and logical conflict, the terms and / or descriptions among the various embodiments are consistent and can be referenced to each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0113] It should be understood that in the present application, "at least one (item)" means one or more, "a plurality" means two or more, "at least two (items)" means two or three or more, and "and / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: only A exists, only B exists, and both A and B exist simultaneously. Among them, A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one (one) of the following" or its similar expression means any combination of these items, including any combination of single item (one) or plural items (ones). For example, at least one (one) of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0114] As described in the background art section, there is a walk-off effect in current lidars, which makes it difficult for the reflected optical signal to be coupled into the silicon photonic chip through the waveguide, resulting in the loss of the reflected optical signal. The present application provides an optical waveguide component and related devices, which relate to the technical field of lidars and can solve the walk-off problem in FMCW lidars.

[0115] To describe the solution of the present application more clearly, some possible application scenarios of lidars are introduced below.

[0116] Please refer to Figure 1A and Figure 1B , Figure 1A and Figure 1B which are schematic diagrams of the application scenarios of the radar provided by the embodiments of the present application.

[0117] As Figure 1A and Figure 1B shown, in this exemplary application scenario, a lidar installed on a vehicle is taken as an example.

[0118] The vehicle can be, for example, an autonomous vehicle, a smart vehicle, an electric vehicle, or a digital car, etc. The lidar can be deployed at various positions of the vehicle (please refer toFigure 1B )。For example, lidar can be deployed in any one or any number of directions among the front, rear, left, and right directions of the vehicle to capture environmental information around the vehicle. Figure 1A Taking the case where lidar is deployed in front of the vehicle as an example. The lidar can sense a fan-shaped area shown by the dashed box as Figure 1A shown. This fan-shaped area can be referred to as the detection area of the lidar (or the field of view of the lidar).

[0119] In a possible implementation, the lidar can obtain the longitude, latitude, speed, orientation of the vehicle itself, or the associated information of targets (such as other surrounding vehicles) within a certain range in real time or periodically (such as the distance of the target, the moving speed of the target, the attitude of the target, or the grayscale image of the target, etc.). The lidar or the vehicle can determine the position and / or path planning of the vehicle based on this associated information. For example, the position of the vehicle can be determined using longitude and latitude, or the driving direction and destination of the vehicle in the next period of time can be determined using speed and orientation, or the number and density of obstacles around the vehicle can be determined using the distance of surrounding objects. Further, optionally, in combination with the functions of an advanced driving assistance system (ADAS), assisted driving or autonomous driving of the vehicle can be achieved. It should be understood that the principle of the lidar detecting the associated information of the target is: the lidar emits detection light in a certain direction. If there is a target within the detection area of the lidar, the target can reflect the received detection light back to the lidar (the reflected detection light can be called the echo signal), and the lidar then determines the associated information of the target based on the echo signal.

[0120] It should be noted that the above application scenarios are only examples. The lidar provided in this application (this lidar includes the optical waveguide component provided in this application) can also be applied in a variety of other possible scenarios, and is not limited to the scenarios exemplified above. For example, the lidar can also be installed on a drone as an airborne radar. Another example is that the lidar can be installed on a roadside unit (RSU) as a roadside traffic lidar to achieve intelligent vehicle-road collaborative communication. Another example is that the lidar can be installed on an automated guided vehicle (AGV), where AGV refers to a transport vehicle equipped with electromagnetic or optical and other automatic navigation devices that can travel along a specified navigation path and has safety protection and various transfer functions. They will not be listed one by one here. It should be understood that the application scenarios described in this application are for more clearly explaining the technical solutions of this application, and do not constitute a limitation on the technical solutions provided in this application. Those of ordinary skill in the art know that with the emergence of new application scenarios, the technical solutions provided in this application are equally applicable to similar technical problems.

[0121] Based on the above content, the above application scenarios can be applied to fields such as driverless, autonomous driving, assisted driving, intelligent driving, connected vehicles, security monitoring, remote interaction, surveying and mapping, or artificial intelligence.

[0122] Next, in combination with Figure 2A and Figure 2B , some knowledge related to lidar will be introduced.

[0123] Lidar, also known as optical radar, is short for a light detection and ranging system, and can also be called Laser Radar or LADAR (laser detection and ranging).

[0124] Lidar uses light as the detection medium. It utilizes the emission and reception of laser to achieve the detection of targets, such as distance measurement, speed measurement, or azimuth angle measurement, etc. Lidar can achieve distance measurement of targets based on the flight time of laser, that is, the time difference between laser transmission and reception. Or, lidar can achieve distance measurement of targets based on the phase difference between the transmitted laser signal and the echo signal of the received laser signal. The biggest advantage of lidar lies in its ability to use Doppler imaging technology to create a clear three-dimensional (3D) image of the target. Lidar uses the emission and reception of laser to collect information such as the three-dimensional coordinates, reflectivity, and texture of a large number of dense points on the target surface, and obtains a three-dimensional model of the measured target based on the collected information, establishes a three-dimensional point cloud map, and draws an environmental map to achieve the purpose of environmental perception. Compared with traditional passive imaging technologies such as visible light and infrared rays, lidar imaging technology subverts the traditional two-dimensional projection imaging mode, can collect the depth information of the target surface, obtain relatively complete spatial information of the target, reconstruct the three-dimensional surface of the target through data processing, obtain a three-dimensional graph that can better reflect the geometric shape of the target, and at the same time can also obtain rich characteristic information such as the reflection characteristics and motion speed of the target surface, providing sufficient information support for data processing such as target detection, recognition, and tracking, and reducing the algorithm difficulty.

[0125] Please refer to Figure 2A , Figure 2A which is a schematic diagram of the architecture of a radar provided by an embodiment of the present application.

[0126] As Figure 2A shown, the lidar mainly includes a laser emission part (or system) 100, a laser reception part (or system) 200, and a signal processing part (or system) 300.

[0127] Among them, the laser emission part 100 includes an excitation source (or a laser driver), a laser, and an emission optical system. The excitation source drives the laser to emit a laser beam (or a laser pulse), and the laser beam (or laser pulse) is emitted outward through the emission optical system. The laser reception part 200 includes a reception optical system and a detector; after the laser beam emitted from the lidar encounters a target object, an echo beam of reflection / scattering is formed by interacting with the target object. After the echo beam is collected by the reception optical system, it is received by the detector, the optical signal is converted into an electrical signal, and the electrical signal is transmitted to the signal processing part 300 after being processed by the analog front end. The processing part 300 processes the received signal to obtain information such as the distance, speed, and azimuth angle of the target object. In addition, information such as the surface morphology and physical properties of the target can be obtained to establish an object model. The detector is usually a photoelectric detector that converts the received optical signal into an electrical signal. This electrical signal is usually an analog signal, while the signal processing part 300 is usually used to process digital signals, such as a digital signal processor (DSP). Therefore, the analog electrical signal is converted into a digital signal by an analog-to-digital converter (ADC) and provided to the signal processing part 300. In addition, the electrical signal can also be amplified, and the amplified electrical signal is converted into a digital signal by the analog-to-digital converter and then provided to the signal processing part 300. The signal processing part 300 includes a signal processing circuit for processing the digital signal to obtain information such as the distance, speed, and azimuth angle of the target object and further establish an object model. The lidar also includes a control circuit, such as a control part for controlling the excitation source and a control part for controlling the scanning drive circuit. These two control parts can be integrated or set independently. In addition, the signal processing circuit and the control circuit can also be integrated or set independently.

[0128] In addition, in one implementation, the laser emission part 100 may further include a laser modulator and a beam controller. The laser beam emitted by the laser passes through the beam controller. Under the control of the laser modulator, the beam controller controls the direction and number of lines of the emitted laser beam, and the laser beam emitted from the beam controller is emitted outward through the emission optical system.

[0129] In addition, the lidar may further include a scanning part (or system) 400. Under the action of the scanning part 400, the laser beam emitted by the laser realizes the scanning of the laser beam on a plane to generate real-time plan view information. The scanning part 400 mainly includes a scanning mechanism and a scanning drive circuit. The scanning drive circuit is used to drive the scanning mechanism to operate. Under the action of the scanning mechanism, the laser beam realizes the change from "line" to "plane".

[0130] Taking the mechanical rotation scanning method as an example, specifically, refer to Figure 2B , Figure 2BSchematic diagram of the architecture of a radar provided by an embodiment of the present application.

[0131] As Figure 2B shown, the scanning drive circuit drives the scanning mechanism to rotate at a stable speed. After the laser beam is incident on the optical element of the emission optical system, the optical element is driven by the scanning mechanism to rotate, and dense scanning of the laser beam is realized on the target plane to generate planar map information. Here, the scanning mechanism is, for example, a motor, and the scanning drive circuit is a motor driver. The rotation of the motor drives the optical element in the emission optical system to rotate, so that the laser beam incident on the optical element is reflected by the optical element, and the effect change from "line scanning" to "plane scanning" of the laser is quickly and accurately realized.

[0132] Currently, FMCW lidars use a combination of a fast-rotating mirror and a slow-rotating mirror for two-dimensional beam scanning. After the silicon optical waveguide emits an optical signal, it is irradiated onto the fast-rotating mirror through the transmitting optical lens. After being reflected by the object to be measured, it passes through the folding mirror and the receiving optical lens and is coupled to the silicon optical chip. After the beam is reflected by the target, due to the different distances of the objects to be measured, the delay times of the backscattered optical signals at short distances and long distances are different. When the scanning mirror rotates continuously, a delay angle related to the target distance will be generated Delay angle has the following relationship with the distance L of the object to be measured, the speed of light c, and the angular velocity v of the rotating mirror:

[0133]

[0134] Due to the existence of the delay angle, the transmission paths of the backscattered optical signals at short distances and long distances before and after passing through the scanning device are no longer the same, and they are offset relative to the position of the receiving waveguide, that is, the walk-off effect occurs, which will cause the backscattered optical signal to be difficult to be coupled into the silicon optical chip through the waveguide, and then cause the loss of the backscattered optical signal.

[0135] In view of this, the present application provides an optical waveguide component and related devices, which relate to the technical field of lidar, and can realize that the input backscattered optical signal at a long distance is transmitted to the output port according to the configured transmittance, so that the loss of the backscattered optical signal corresponding to the long-distance target is small, while the loss of the backscattered optical signal corresponding to the short-distance target is large, so as to realize that no matter how the position of the backscattered optical signal corresponding to the long-distance target walks off, a certain intensity of backscattered optical signal can always be received and output, solve the walk-off problem in FMCW lidar, and can realize the relative balance of the backscattered optical signal corresponding to the received long-distance target and the backscattered optical signal corresponding to the short-distance target, and at the same time reduce the number of components required for the optical waveguide component.

[0136] Next, the optical waveguide component and related devices provided by the present application will be described with reference to the accompanying drawings.

[0137] Please refer to Figure 3 , Figure 3 which is a schematic structural diagram of an optical waveguide component provided by an embodiment of the present application.

[0138] As Figure 3 shown, the optical waveguide component includes:

[0139] M first coupling units and a first optical signal processing component.

[0140] The first optical signal processing component has M first ports (such as ports 1, 2, …, m, …, M in Figure 3 ) and N second ports (such as ports 1, 2, …, n, …, N in Figure 3 ), where M is an integer greater than or equal to 3, N is an integer greater than or equal to 2, and N is less than or equal to M.

[0141] The M first coupling units are respectively connected to the M first ports of the first optical signal processing component in one-to-one correspondence.

[0142] Among them, the first optical signal processing component includes at least M - 2 first phase control units and at least two power distribution units.

[0143] The first phase control units are arranged between the first coupling units and the power distribution units, or the first phase control units are arranged between any two of the at least two power distribution units.

[0144] It can be understood that all of the above at least M - 2 first phase control units are arranged between the first coupling units and the power distribution units, or all of the above at least M - 2 first phase control units are arranged between any two of the above at least two power distribution units, or some of the above at least M - 2 first phase control units are arranged between the first coupling units and the power distribution units, and the other part of the first phase control units are arranged between any two of the above at least two power distribution units. The embodiments of the present application do not limit this.

[0145] Optionally, the M first coupling units and the first optical signal processing component can be high-density integrated chip components, which can reduce the overall volume of the optical waveguide component system.

[0146] Among them, the M first coupling units are used to couple the optical signal in the spatial light field to the first optical signal processing component, or can also couple the optical signal output by the first optical signal processing component to the spatial light field. Therefore, the optical waveguide component in the embodiments of the present application is applicable to both signal reception scenarios and signal transmission scenarios. The embodiments of the present application do not limit this.

[0147] The first optical signal processing component has M first ports and N second ports. Through the internal structure of the optical waveguide component, M-channel signal input and N-channel signal output can be achieved, or N-channel signal input and M-channel signal output can also be achieved.

[0148] It can be understood that when the optical waveguide component in the embodiment of the present application is applied to a signal receiving scenario, the M first ports are signal input ports, and the N second ports are signal output ports. When the optical waveguide component in the embodiment of the present application is applied to a signal sending scenario, the N second ports are signal input ports, and the M first ports are signal output ports.

[0149] The first optical signal processing component can transmit the input optical signal to the output port at any configured transmittance through at least two internal power distribution units. For example, the optical signal input from the M first ports can be transmitted to any one or more of the N second ports at any configured transmittance, or the optical signal input from any one or more of the N second ports can be transmitted to the M first ports at any configured transmittance.

[0150] It can be understood that when there is only one first port and one second port with signal input or output, the configured transmittance is a value. When there are signal inputs or outputs at both the M first ports and the N second ports, the configured transmittance includes M×N values.

[0151] It can be understood that transmitting at any configured transmittance can be understood as pre-configuring the required transmittance according to any application scenario, or it can also be understood as adjusting the configured transmittance in real time according to the changing requirements of the application scenario during the transmission process. The present application does not limit this.

[0152] At least M-2 first phase control units in the first optical signal processing component are used to adjust the phase of the transmitted optical signal, so that after the nth second port satisfies the phase matching condition, the energy of the output optical signal can be expressed as T = P1×S1n + P2×S2n + … + Pm×Smn, where S1n, S2n, …, Smn respectively represent the transmittances corresponding to the optical signals input from the first first port to the mth first port and output from the nth second port, and P1, P2, …, Pm respectively represent the powers of the optical signals input from the first first port to the mth first port. It can be seen that through the cooperation of at least M-2 first phase control units and at least two power distribution units, the energy of the optical signal output from the nth second port corresponding to the optical signal input from any first port can be relatively balanced, that is, P1×S1n, P2×S2n, …, Pm×Smn are relatively balanced, so as to achieve that no matter how the position of the backscattered optical signal corresponding to the long-distance target changes, a backscattered optical signal with a certain intensity can always be received and output.

[0153] Optionally, the first phase control unit can be arranged between the first coupling unit and the power distribution unit, or can be arranged between any two of at least two power distribution units. The present application does not limit this.

[0154] Optionally, when the first phase control unit is arranged between the first coupling unit and the power distribution unit, specifically: the above at least M-2 first phase control units are cascade-connected with M first coupling units.

[0155] Optionally, when the number of first phase control units is M, the M first phase control units are respectively connected to the M first coupling units in one-to-one correspondence. Exemplarily, as Figure 4A shown, assuming that there are 4 first coupling units and also 4 first phase control units, then the 4 first phase control units are respectively connected to the 4 first coupling units in one-to-one correspondence, and the 4 first phase control units are respectively connected to at least two power distribution units.

[0156] Optionally, when the number of first phase control units is less than M, the at least M-2 first phase control units are respectively connected to one first coupling unit, and the other first coupling units not connected to the first phase control unit are directly connected to the above power distribution unit. Exemplarily, as Figure 4B shown, assuming that there are 4 first coupling units and 2 first phase control units, then the 2 first phase control units are respectively connected to the 2 first coupling units in one-to-one correspondence, and the other 2 first coupling units not connected to the first phase control unit are directly connected to the above power distribution unit.

[0157] Optionally, when the number of the first phase-controlled units is greater than M, the M first coupling units are connected to the M first phase-controlled units in a one-to-one correspondence, and the redundant first phase-controlled units are connected to some of the first coupling units. Figure 4C As shown, assuming that there are 4 first coupling units and 6 first phase-controlled units, the 4 first coupling units are connected to the 4 first phase-controlled units one by one, and in addition, the extra 2 first phase-controlled units are respectively arranged between the 2 first coupling units and the power distribution unit, that is, the 2 first coupling units are connected to multiple first phase-controlled units.

[0158] The first phase-controlled unit provided in the embodiment of the present application can be used to adjust the phase of the transmitted optical signal so as to meet the phase matching condition, thereby ensuring that when the echo signal is received, coherent superposition is performed according to the preset transmittance to reduce energy loss.

[0159] At present, after the outgoing light beam from the laser radar transmitter is reflected by the target, the delay time of the short-range echo light signal and the long-range echo light signal is different due to the different distances of the target to be measured. When the scanning mirror continues to rotate, a delay angle related to the target distance will be generated. Due to the existence of the delay angle, the transmission paths of the short-range echo light signal and the long-range echo light signal are no longer consistent before and after passing through the scanning device, and they are offset relative to the receiving waveguide position, which produces a walk-off effect. This makes it difficult for the echo light signal to be coupled to the silicon photonic chip through the waveguide, which in turn causes the echo light signal to be lost.

[0160] In the embodiment of the present application, the long-distance echo optical signal can be received by M first coupling units and transmitted to the first optical signal processing component, the first phase control unit in the first optical signal processing component adjusts the phase thereof, and the power distribution unit in the first optical signal processing component transmits the input long-distance echo optical signal to the output port according to the configured transmittance, so that the loss of the echo optical signal corresponding to the long-distance target is smaller, while the loss of the echo optical signal corresponding to the close-range target is larger, thereby achieving that no matter how the position of the echo optical signal corresponding to the long-distance target walks away, an echo optical signal of a certain intensity can always be received and output, thereby solving the walk-away problem in the FMCW laser radar, and achieving relative balance between the received echo optical signal corresponding to the long-distance target and the echo optical signal corresponding to the close-range target, while reducing the number of components required for the optical waveguide component.

[0161] In a possible embodiment, when the optical waveguide component is an optical signal receiving component, the M first ports are used to receive optical signals, and the first optical signal processing component processes the optical signals received by the M first ports, and the corresponding transmittance increases along the first direction.

[0162] It can be understood that when the optical waveguide component is an optical signal receiving component, the M first ports are used to receive optical signals, and the nth port among the N second ports is used to output the optical signal processed by the first optical signal processing component.

[0163] After the first optical signal processing component processes the optical signals received by the M first ports, the corresponding transmittance increases along the first direction. Optionally, the first direction may be a walk-off direction of the optical signal.

[0164] For details, please refer to Figure 4D , Figure 4D A schematic diagram of an application scenario of an optical waveguide component provided in an embodiment of the present application.

[0165] like Figure 4D As shown, it can be understood that after the outgoing light beam from the laser radar transmitting end is reflected by the target, due to the different distances of the target to be measured, the delay time of the short-range echo light signal and the long-range echo light signal is different. When the scanning mirror continues to rotate, a delay angle related to the target distance will be generated. Due to the existence of the delay angle, the transmission paths of the short-range echo light signal and the long-range echo light signal before and after passing through the scanning device are no longer consistent, and the position relative to the receiving waveguide is offset, which produces a walk-off effect. Figure 4D The solid line in the figure represents the transmission path of the short-range echo optical signal. Figure 4D The dotted line in the figure represents the transmission path of the long-distance echo optical signal. Figure 4D The x direction in the figure is the walk-off direction of the echo light signal. Along the walk-off direction of the echo light signal, the long-distance echo light signal is difficult to couple into the silicon photonic chip through the waveguide, which results in the loss of part of the long-distance echo light signal.

[0166] In the embodiment of the present application, the long-distance echo optical signal that has walked away can be received by M first coupling units and transmitted to the first optical signal processing component. The power distribution unit in the first optical signal processing component transmits the input long-distance echo optical signal to the output port according to the configured transmittance, and the first optical signal processing component processes the optical signals received by the M first ports, and the corresponding transmittance increases along the first direction (i.e., the x direction).

[0167] For example, the increase in the transmittance along the first direction can be expressed as S1n≤S2n≤…≤Smn.

[0168] Among them, 1, 2, ..., m are the corresponding port numbers of the M first ports arranged in sequence from receiving the long-distance echo light signal to receiving the short-distance echo light signal (i.e., the opposite direction of the departure direction of the echo light signal), m is a positive integer less than or equal to M, n is one of the port numbers of the N second ports, n is a positive integer less than or equal to N, and Smn represents the corresponding transmittance output from the nth second port after the optical signal received by the mth first port is processed.

[0169] It can be understood that receiving, processing, and outputting the optical signal according to the embodiments of the present application can make the loss of the reflected optical signal corresponding to the long-distance target relatively small, while the loss of the reflected optical signal corresponding to the short-distance target is relatively large. Thus, no matter how the position of the reflected optical signal corresponding to the long-distance target moves away, a reflected optical signal with a certain intensity can always be received and output. Moreover, it can achieve a relatively balanced reflected optical signal corresponding to the long-distance target and the reflected optical signal corresponding to the short-distance target received, while reducing the number of components required for the optical waveguide component.

[0170] Exemplarily, assume that the transmitting unit is located at a position below the center of the Mth coupling unit. When there is no walk-off of the receiving spot of the lidar, the position of the receiving spot is the same as that of the transmitting spot, and the receiving spot is located at a position below the center of the Mth coupling unit (the distance from the Mth coupling unit is d). Only a small part of the reflected light can enter the receiving component through the Mth coupling unit. When walk-off occurs, when the reflected light spot is located at any position between the transmitting unit and the Mth coupling unit, the receiving component can receive the reflected optical signal.

[0171] If the reflected optical signal spot is focused at the center position of the Mth coupling unit and the power of the reflected light spot signal is P, then the optical power output through the optical waveguide receiving component is P×S M1 . If the reflected optical signal spot is focused at the center position of the (M - 1)th coupling unit, then the optical power output through the optical waveguide receiving component is P×S (M-1)1 .

[0172] If the reflected optical signal spot is focused at any position between the Mth coupling unit and the (M - 1)th coupling unit, the distance from the focused spot to the center position of the Mth coupling unit is dx1, and the distance from the focused spot to the center position of the (M - 1)th coupling unit is dx2, then the optical signal power output through the optical waveguide component is approximately:

[0173]

[0174] It can be understood that when the reflected optical signal spot is focused at other positions, a similar effect as above also exists.

[0175] Optionally, the distance between the transmitting unit and the Mth coupling unit is about greater than 0.2d and less than 2d.

[0176] Optionally, the emitting unit has the same structure as the above-mentioned coupling unit. The waveguide width at the incident end is approximately greater than 200 nm and less than 800 nm. The above-mentioned coupling unit gradually increases along the propagation direction of the received signal. The increasing trend can be linearly variable or non-linearly variable along the propagation direction. For example, it can be a quadratic curve change. The embodiments of the present application do not limit this.

[0177] Optionally, when the above optical waveguide assembly is an optical signal receiving assembly, the sum s1 of the M transmittances corresponding to the optical signals received by the M first ports after being processed by the first optical signal processing assembly satisfies the following condition: 0.9 ≤ s1 ≤ 1.

[0178] It can be understood that when the optical waveguide assembly is an optical signal receiving assembly, the M first ports are used to receive optical signals, and the nth second port among the N second ports is used to output the optical signal after being processed by the first optical signal processing assembly.

[0179] Among them, the sum s1 of the M transmittances corresponding to the optical signals received by the M first ports after being processed by the first optical signal processing assembly is within the interval [0.9, 1].

[0180] For example, the increase of the above M transmittances along the walk-off direction of the optical signal can be expressed as S1n ≤ S2n ≤ …… ≤ Smn.

[0181] Among them, 1, 2, ……, m are the port numbers corresponding to the M first ports arranged in sequence from receiving the far-distance echo optical signal to receiving the near-distance echo optical signal (i.e., the opposite direction of the walk-off direction of the echo optical signal). m is a positive integer less than or equal to M. n is one of the port numbers of the N second ports, and n is a positive integer less than or equal to N. Smn represents the transmittance corresponding to the optical signal received by the mth first port and output from the nth second port after being processed. Then s1 = S1n + S2n + …… + Smn is within the interval [0.9, 1], that is

[0182] In a possible embodiment, when the above optical waveguide assembly is an optical signal transmitting assembly, the M first ports are used to transmit optical signals, and the transmittances corresponding to the optical signals transmitted by the M first ports after being processed by the first optical signal processing assembly increase along the second direction.

[0183] It can be understood that when the optical waveguide assembly is an optical signal transmitting assembly, the nth second port among the N second ports is used to receive optical signals, and the M first ports are used to output the optical signals after being processed by the first optical signal processing assembly.

[0184] Among them, the transmittance corresponding to the optical signals sent by the M first ports after being processed by the first optical signal processing component increases along the second direction. Optionally, the second direction may be the direction in which the optical signals move away.

[0185] For details, please refer to Figure 4D , Figure 4D which is a schematic diagram of an application scenario of an optical waveguide component provided by an embodiment of the present application.

[0186] As Figure 4D shown, it can be understood that the transmission paths of the near-range outgoing optical signals and the far-range outgoing optical signals of the lidar transmitter before and after passing through the scanning device are inconsistent. When there is an offset relative to the position of the outgoing waveguide, the walk-off effect occurs. Figure 4D The solid line in Figure 4D represents the transmission path of the near-range outgoing optical signal, Figure 4D and the dashed line in

[0187] represents the transmission path of the far-range outgoing optical signal. The x direction in

[0188] is the walk-off direction of the outgoing optical signal. Along the walk-off direction of the outgoing optical signal, it is difficult for the far-range outgoing optical signal to be coupled to the target through the waveguide, resulting in inaccurate detection of some far-range targets.

[0189] In the embodiment of the present application, the far-range outgoing optical signal with walk-off can be transmitted to the M first coupling units for emission after being processed by the first optical signal processing component. The power distribution unit in the first optical signal processing component transmits the input far-range outgoing optical signal to the output port according to the configured transmittance. Moreover, the transmittance corresponding to the optical signals sent by the M first ports after being processed by the first optical signal processing component increases along the second direction (i.e., the x direction).

[0190] It can be understood that receiving, processing, and outputting the optical signal according to the embodiments of the present application can result in a relatively small loss of the backscattered optical signal corresponding to a long-distance target, while a relatively large loss of the backscattered optical signal corresponding to a short-distance target. Thus, regardless of how the position of the backscattered optical signal corresponding to the long-distance target deviates, a certain intensity of the backscattered optical signal can always be received and output. Moreover, it can be achieved that the backscattered optical signal corresponding to the long-distance target and the backscattered optical signal corresponding to the short-distance target received are relatively balanced. As a result, the echo signals from both short-distance and long-distance targets can be received simultaneously at one output end, reducing the dynamic range requirement of the subsequent trans-impedance amplifier (TIA). Compared with the method of using multiple waveguides to receive the deviating light spot separately, the embodiments of the present application can reduce the number of components required for the receiving system.

[0191] Optionally, when the above optical waveguide assembly is an optical signal transmitting component, the sum s2 of the M transmittances corresponding to the optical signals transmitted from the M first ports after being processed by the first optical signal processing component satisfies the following condition: 0.9 ≤ s2 ≤ 1.

[0192] It can be understood that when the optical waveguide assembly is an optical signal transmitting component, the nth second port among the N second ports is used to receive the optical signal, and the M first ports are used to output the optical signal after being processed by the first optical signal processing component.

[0193] Among them, the sum s2 of the M transmittances corresponding to the optical signals transmitted from the M first ports after being processed by the first optical signal processing component is within the interval [0.9, 1].

[0194] For example, the increase of the above M transmittances along the deviating direction of the optical signal can be expressed as Sn1 ≤ Sn2 ≤ …… ≤ Snm.

[0195] Where n is the port number of one of the N second ports for receiving the optical signal, n is a positive integer less than or equal to N, 1, 2, ……, m are the port numbers corresponding to the M first ports arranged in sequence from transmitting the long-distance optical signal to transmitting the short-distance optical signal, m is a positive integer less than or equal to M, Snm represents the transmittance corresponding to the optical signal received by the nth second port and output from the mth first port after being processed. Then, s2 = Sn1 + Sn2 + …… + Snm is within the interval [0.9, 1], that is

[0196] In a possible embodiment, the above components are connected by waveguides.

[0197] Optionally, the channels of the above components and waveguides are composed of a cladding, at least one core layer, and a substrate.

[0198] Specifically, reference can be made toFigure 5A and Figure 5B , Figure 5A and Figure 5B are cross-sectional schematic diagrams of an optical waveguide provided by an embodiment of the present application.

[0199] As Figure 5A shown, the above-mentioned various components and the channels of the waveguide are composed of a cladding, 1 core layer, and a substrate.

[0200] As Figure 5B shown, the above-mentioned various components and the channels of the waveguide are composed of a cladding, 2 core layers (core layer 1, core layer 2), and a substrate.

[0201] Optionally, the core layer material can be silicon, silicon dioxide, silicon nitride, silicon oxynitride, polysilicon, lithium niobate, etc., and the cladding and substrate materials can be silicon dioxide, silicon oxynitride, polymer, silicon, etc. Optionally, the refractive index of the core layer material should be greater than that of the cladding material to ensure the transmission of optical signals in the core layer.

[0202] In a possible embodiment, the above-mentioned optical waveguide assembly further includes:

[0203] A monitoring unit.

[0204] The monitoring unit is used to monitor the power of the optical signal in the first optical path from the above-mentioned spatial light field.

[0205] It can be understood that the monitoring unit is applicable to the signal reception scenario, which is beneficial to the assembly and adjustment of the radar system to which the optical waveguide assembly is applied. During the assembly process of the optical component, it is necessary to couple the optical signal into the receiving component under static conditions (without a scanner). By setting the monitoring unit, the static spot position can be quickly aligned with the coupling unit. Therefore, the monitoring unit can monitor the working state of the receiving component under static conditions and can be used for the self-check of the lidar system.

[0206] Optionally, the monitoring unit can be a surface-mounted photodetector, an integrated photodetector in a chip, or can also be connected to an external photodetector through an optical fiber, etc. The embodiments of the present application do not limit this.

[0207] Optionally, when the monitoring unit is set at different positions, the corresponding first optical path it monitors is also different. The following describes several possible situations:

[0208] Situation 1:

[0209] The monitoring unit is connected to the first output port of the first optical signal processing component.

[0210] Accordingly, the first optical path is the optical path through which the short-distance echo optical signal from the above-mentioned spatial optical field sequentially passes through the above-mentioned first coupling unit and the above-mentioned first optical signal processing component and is output from the first output port of the above-mentioned first optical signal processing component.

[0211] In the first case, the first optical path monitored by the monitoring unit is the optical path through which the short-distance echo optical signal from the spatial optical field sequentially passes through the first coupling unit and the first optical signal processing component and is output from the first output port of the first optical signal processing component.

[0212] Optionally, the first output port may be a port with input / output (I / O) function.

[0213] Through the embodiments of the present application, one of the N second ports of the first optical signal processing component can be borrowed as the first output port for connecting with the monitoring unit to realize the alignment of the radar system applied by the optical waveguide component.

[0214] Case two:

[0215] The monitoring unit is connected to the second output port.

[0216] Accordingly, the first optical path is the optical path through which the short-distance echo optical signal from the above-mentioned spatial optical field passes through the above-mentioned first coupling unit and is output from the second output port.

[0217] In the second case, the first optical path monitored by the monitoring unit is the optical path through which the short-distance echo optical signal from the spatial optical field passes through the first coupling unit and is output from the second output port.

[0218] Optionally, the second output port may be a port with input / output (I / O) function.

[0219] Through the embodiments of the present application, the N second ports of the first optical signal processing component can be not occupied, but a path of optical signal coupled by a first coupling unit alone is used as the second output port for connecting with the monitoring unit to realize the alignment of the radar system applied by the optical waveguide component.

[0220] In a possible embodiment, the number of layers x formed by cascading at least two power distribution units in the first optical signal processing component in the above-mentioned optical waveguide component satisfies the following condition: p ≤ x ≤ q.

[0221] Wherein, x is an integer greater than 1, q is an integer greater than 1 and satisfies the following condition: q = M - 1, p is an integer greater than 1 and satisfies the following condition: 2 p-1 <m≤2 p 。

[0222] Optionally, when the first optical signal processing component has M = 3 first ports, p = 2, q = 2, then: the number of layers x formed by cascading at least two power distribution units is 2.

[0223] Optionally, when the first optical signal processing component has M = 4 first ports, p = 2, q = 3, then: the number of layers x formed by cascading at least two power distribution units is 2 or 3.

[0224] Optionally, when the first optical signal processing component has M = 5 first ports, p = 3, q = 4, then: the number of layers x formed by cascading at least two power distribution units is 3 or 4.

[0225] Optionally, when the first optical signal processing component has M = 6 first ports, p = 3, q = 5, then: the number of layers x formed by cascading at least two power distribution units is 3 or 4 or 5.

[0226] Optionally, when the first optical signal processing component has M = 7 first ports, p = 3, q = 6, then: the number of layers x formed by cascading at least two power distribution units is 3 or 4 or 5 or 6.

[0227] Optionally, when the first optical signal processing component has M = 8 first ports, p = 3, q = 7, then: the number of layers x formed by cascading at least two power distribution units is 3 or 4 or 5 or 6 or 7.

[0228] And so on, which will not be elaborated here.

[0229] Exemplarily, as follows Figure 6 shown, when the first optical signal processing component has M = 4 first ports, p = 2, q = 3, then: the first 2×2 directional coupler forms the first layer, the first 1×2 multimode interferometer forms the second layer, and the second 1×2 multimode interferometer forms the third layer, that is, the number of layers x formed by cascading at least two power distribution units is 3.

[0230] Exemplarily, as follows Figure 8 shown, when the first optical signal processing component has M = 4 first ports, p = 2, q = 3, then: the first 2×2 directional coupler forms the first layer, the second 2×2 directional coupler forms the second layer, and the first 1×2 multimode interferometer forms the third layer, that is, the number of layers x formed by cascading at least two power distribution units is 3.

[0231] Exemplarily, as follows Figure 9As shown, when the first optical signal processing component has M = 4 first ports, p = 2, and q = 3, then: the first 2×2 directional coupler forms the first layer, the second 2×2 directional coupler forms the second layer, and the third 2×2 directional coupler forms the third layer, that is, the number of layers x formed by cascading at least two power distribution units is x = 3.

[0232] Exemplarily, as follows Figure 10 As shown, when the first optical signal processing component has M = 4 first ports, p = 2, and q = 3, then: the first 2×2 directional coupler and the second 2×2 directional coupler form the first layer, and the third 2×2 directional coupler forms the second layer, that is, the number of layers x formed by cascading at least two power distribution units is x = 2.

[0233] Exemplarily, as follows Figure 11 As shown, when the first optical signal processing component has M = 5 first ports, p = 3, and q = 4, then: the first 2×2 directional coupler forms the first layer, the first 1×2 multimode interferometer forms the second layer, the second 1×2 multimode interferometer forms the third layer, and the third 1×2 multimode interferometer forms the fourth layer, that is, the number of layers x formed by cascading at least two power distribution units is x = 4.

[0234] Through the embodiments of the present application, the number of layers x formed by cascading at least two power distribution units in the first optical signal processing component of the optical waveguide component satisfies p ≤ x ≤ q, and it is possible to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide component.

[0235] In a possible embodiment, the above power distribution unit includes at least one of the following:

[0236] Directional coupler, multimode interferometer, star coupler, adjustable ratio coupler, Y-branch splitter.

[0237] It should be understood that the several power distribution units listed in the embodiments of the present application are only for possible exemplary illustration, and should not be used to limit the embodiments of the present application. New possible power distribution units obtained by reasonable deformation, supplement, or combination of the power distribution units in the embodiments of the present application all fall within the protection scope of the embodiments of the present application.

[0238] Next, the components that the above power distribution unit may include will be described with specific examples.

[0239] Exemplary One:

[0240] The above at least two power distribution units include: a first 2×2 directional coupler, a first 1×2 multimode interferometer, and a second 1×2 multimode interferometer.

[0241] One side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascaded with the first 1×2 multimode interferometer and the second 1×2 multimode interferometer in sequence.

[0242] For details, please refer to Figure 6 , Figure 6 which is a schematic structural diagram of an optical waveguide component provided by an embodiment of the present application.

[0243] As Figure 6 shown, the optical waveguide component includes 4 coupling units (coupling unit 1, coupling unit 2, coupling unit 3, coupling unit 4) and a first optical signal processing component.

[0244] The 4 coupling units are arranged along the x direction (the direction in which the optical signal travels away).

[0245] Optionally, the interval between two adjacent coupling units is about 4-8 μm.

[0246] Optionally, the mode field size of the input ends of the 4 coupling units is about 4-8 um.

[0247] Optionally, the cross-sectional width of the 4 coupling units gradually increases to the size at which the single-mode optical signal is stably transmitted along the optical signal propagation direction, and can be in a tapered structure, an inverted tapered structure, or other structural forms.

[0248] The first optical signal processing component has M = 4 first ports and N = 2 second ports.

[0249] Among them, the first optical signal processing component includes 4 first phase control units (phase control unit 1, phase control unit 2, phase control unit 3, phase control unit 4) and at least two power distribution units (the first 2×2 directional coupler, the first 1×2 multimode interferometer, the second 1×2 multimode interferometer).

[0250] The input ends of the above-mentioned coupling units are used to receive optical signals in free space, and the output ends are connected to the input ends of the phase control units through waveguides. The phase control units are used to adjust the phases of the transmitted optical signals.

[0251] Optionally, the phase control unit can be a passive waveguide phase compensator with a variable width, or can be a thermo-optic phase shifter, an electro-optic phase shifter, a phase change material phase shifter, etc. The embodiments of the present application do not limit this.

[0252] Optionally, the number of phase control units is at least M-2. In the embodiments of the present application, M = 4, so the number of phase control units can be 2, 3, or 4. Figure 6The number of phase control units shown is 4, which should not limit the embodiments of this application.

[0253] Optionally, the phase control unit can be fabricated in the core layer 1 as shown in Figure 5B or in other core layers. The embodiments of this application do not limit this.

[0254] One side port of the above-mentioned first 2×2 directional coupler is connected to the coupling unit or the phase control unit, and the other side port of the first 2×2 directional coupler is cascaded with the above-mentioned first 1×2 multimode interferometer and the second 1×2 multimode interferometer in sequence. The output port of the second 1×2 multimode interferometer is used to output optical signals.

[0255] Optionally, the above-mentioned 2×2 directional coupler (such as the first 2×2 directional coupler) can be composed of two parallel waveguides, and by setting the coupling ratio, the input optical signal can be transmitted to the output port according to the configured transmittance.

[0256] Specifically, reference can be made to Figure 7 , Figure 7 which is a schematic structural diagram of a directional coupler provided by the embodiments of this application.

[0257] As shown in Figure 7 , the 2×2 directional coupler includes two input ports and two output ports. The two input ports and the two output ports are connected by two parallel waveguides. One of the two output ports serves as a signal intersection, and the other output port serves as a signal through-port.

[0258] Optionally, the coupling ratio of the 2×2 directional coupler can be 0.4. In this case, when input from any one end of the 2×2 directional coupler, the ratio of the optical signal power at the intersection to the optical signal power at the through-port is 0.4. When the input optical signal power is P, the output optical signal power at the intersection is 0.4P, and the output optical signal power at the through-port is 0.6P.

[0259] In the optical waveguide assembly shown above Figure 6 , along the optical signal propagation direction (i.e., the y direction), the 1×2 multimode interferometer (such as the first 1×2 multimode interferometer and the second 1×2 multimode interferometer) includes two input ports and one output port.

[0260] Optionally, the transmittance from any input port to the output port can be 0.5. For example, when an optical signal with power P is input through any port of the 1×2 multimode interferometer, the output power is 0.5P.

[0261] At this time, in the above-mentioned first optical signal processing component, the transmittance of the optical signal transmitted through the phase control unit 1 to the output port of the second 1×2 multimode interferometer is S11≤0.5, the transmittance of the optical signal transmitted through the phase control unit 2 to the output port of the second 1×2 multimode interferometer is S21≤0.25 (i.e., 0.5×0.5 = 0.25), the transmittance of the optical signal transmitted through the phase control unit 3 to the output port of the second 1×2 multimode interferometer is S31≤0.15 (i.e., 0.6×0.5×0.5 = 0.15), and the transmittance of the optical signal transmitted through the phase control unit 4 to the output port of the second 1×2 multimode interferometer is S41≤0.10 (i.e., 0.6×0.5×0.5 = 0.15).

[0262] Among them, the above-mentioned S11 represents the transmittance of the optical signal input from the first input port of the first optical signal processing component and output from the first output port, the above-mentioned S21 represents the transmittance of the optical signal input from the second input port of the first optical signal processing component and output from the first output port, the above-mentioned S31 represents the transmittance of the optical signal input from the third input port of the first optical signal processing component and output from the first output port, and the above-mentioned S41 represents the transmittance of the optical signal input from the fourth input port of the first optical signal processing component and output from the first output port.

[0263] It can be understood that the receiving principle of the laser radar walk-off spot in the embodiments of the present application is as follows:

[0264] The receiving module needs to be used in cooperation with the optical system and the mechanical system. An optical system and a two-dimensional rotating mirror can be placed in front of the receiving module. The optical system converges the received signal into a spot. When the walk-off effect occurs, as the distance of the detected object increases, the offset of the spot along the x direction increases. When the spot walks off, it can be received by at least one coupling unit and enters the first optical signal processing component. The phase control unit in the first optical signal processing component is used to adjust the phase of the transmitted optical signal, and the power distribution unit in the first optical signal processing component is used to transmit the input optical signal to the output port according to the configured transmittance, which makes the backscattered optical signal corresponding to the distant target object have low loss, while the optical signal corresponding to the near target object has strong loss. No matter how the spot position changes (walks off), an output optical signal with a certain intensity can always be received. Therefore, the embodiments of the present application can achieve the reception of the walk-off spot in the detection range and reduce the number of required electrical components at the same time.

[0265] Optionally, the above-mentioned Figure 6 The shown optical waveguide component further includes a monitoring unit.

[0266] The monitoring unit is used to monitor the optical signal power at the second output port of the first optical signal processing component.

[0267] Optionally, the monitoring unit may be a surface-mounted photodetector, an integrated photodetector in a chip, or an external photodetector connected via an optical fiber, etc. The embodiments of the present application do not limit this.

[0268] It can be understood that the beneficial effects of the monitoring unit in the embodiments of the present application during optical alignment are as follows:

[0269] The premise for receiving the walk-off spot is to ensure that the walk-off direction is parallel to the x-direction and remains unchanged in the z-direction. Therefore, during the alignment process, first ensure that the spot satisfies the above walk-off conditions. In the actual alignment process, for the near-distance backward optical signal, the coupling unit 4 has the highest corresponding coupling efficiency and the highest output optical signal efficiency. Therefore, the monitoring unit has the highest accuracy in monitoring the optical signal output from the through port of the first 2×2 directional coupler that sequentially passes through the coupling unit 4, the phase control unit 4, and the first 2×2 directional coupler. At this time, the walk-off direction is parallel to the x-direction and the z-direction remains unchanged.

[0270] It should be understood that the first 2×2 directional coupler, the first 1×2 multimode interferometer, and the second 1×2 multimode interferometer included in at least two power distribution units in the optical waveguide assembly shown in the first exemplary embodiment may be the above Figure 6 shown connection relationship, or other possible connection relationships. Figure 6 Only as a possible exemplary illustration, the embodiments of the present application should not be limited thereby. Based on Figure 6 the reasonable deformation or supplement of the shown connection relationship, the new embodiments obtained all fall within the protection scope of the embodiments of the present application.

[0271] Exemplary Two:

[0272] The above at least two power distribution units include: a first 2×2 directional coupler, a second 2×2 directional coupler, and a first 1×2 multimode interferometer.

[0273] Wherein, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascaded with the second 2×2 directional coupler and the first 1×2 multimode interferometer in sequence.

[0274] Specifically, refer to Figure 8 , Figure 8 which is a schematic structural diagram of an optical waveguide assembly provided by the embodiments of the present application.

[0275] As Figure 8 shown, the optical waveguide assembly includes 4 coupling units (coupling unit 1, coupling unit 2, coupling unit 3, coupling unit 4) and a first optical signal processing component.

[0276] The specific structures of the four coupling units can be referred to the description in the above-mentioned Exemplary One, and will not be elaborated here.

[0277] The first optical signal processing component has M = 4 first ports and N = 3 second ports.

[0278] Among them, the first optical signal processing component includes 4 first phase control units (phase control unit 1, phase control unit 2, phase control unit 3, phase control unit 4) and at least two power distribution units (the first 2×2 directional coupler, the second 2×2 directional coupler, the first 1×2 multimode interferometer).

[0279] The input end of the above-mentioned coupling unit is used to receive the optical signal in free space, and the output end is connected to the input end of the phase control unit through a waveguide. The phase control unit is used to adjust the phase of the transmitted optical signal.

[0280] The specific structure of the phase control unit can be referred to the description in the above-mentioned Exemplary One, and will not be elaborated here.

[0281] One side port of the above-mentioned first 2×2 directional coupler is connected to the coupling unit or the phase control unit. The other side port of the above-mentioned first 2×2 directional coupler is cascaded with the above-mentioned second 2×2 directional coupler and the above-mentioned first 1×2 multimode interferometer in sequence. The output port of the first 1×2 multimode interferometer is used to output the optical signal.

[0282] The specific structures of the directional couplers (the first 2×2 directional coupler, the second 2×2 directional coupler) can be referred to the description of the directional coupler shown above Figure 7 and will not be elaborated here.

[0283] The specific structure of the 1×2 multimode interferometer can be referred to the description in the above-mentioned Exemplary One, and will not be elaborated here.

[0284] It can be seen from the comparison between the optical waveguide component shown in the above-mentioned Exemplary One and the optical waveguide component in this Exemplary Two that the difference between the two is that the 1×2 multimode interferometer is replaced by a 2×2 directional coupler, and the first optical signal processing component with 4×2 ports becomes the first optical signal processing component with 4×3 ports.

[0285] Optionally, the coupling ratio of the first 2×2 directional coupler can be 0.6≥η1≥0.4, and the coupling ratio of the second directional coupler can be 0.6≥η2≥0.4.

[0286] Optionally, the transmittance from any input port to the output port in the first 1×2 multimode interferometer can be 0.5. For example, after an optical signal with power P is input through any port of the first 1×2 multimode interferometer, the output power is 0.5P.

[0287] At this time, in the above first optical signal processing component, the transmittance of the optical signal transmitted through the phase control unit 1 to the output port corresponding to the first 1×2 multimode interferometer is S11≤0.5, the transmittance of the optical signal transmitted through the phase control unit 2 to the output port corresponding to the first 1×2 multimode interferometer is 0.2≤S21≤0.3 (i.e., 0.4×0.5 = 0.2, 0.6×0.5 = 0.3), the transmittance of the optical signal transmitted through the phase control unit 3 to the output port corresponding to the first 1×2 multimode interferometer is 0.08≤S31≤0.18 (i.e., 0.4×0.4×0.5 = 0.08, 0.6×0.6×0.5 = 0.18), and the transmittance of the optical signal transmitted through the phase control unit 4 to the output port corresponding to the first 1×2 multimode interferometer is 0.08≤S41≤0.18 (i.e., 0.4×0.4×0.5 = 0.08, 0.6×0.6×0.5 = 0.18).

[0288] Among them, the above S11 represents the transmittance of the optical signal input from the first input port of the first optical signal processing component and output from the first output port, the above S21 represents the transmittance of the optical signal input from the second input port of the first optical signal processing component and output from the first output port, the above S31 represents the transmittance of the optical signal input from the third input port of the first optical signal processing component and output from the first output port, and the above S41 represents the transmittance of the optical signal input from the fourth input port of the first optical signal processing component and output from the first output port.

[0289] Optionally, the above Figure 8 The shown optical waveguide component further includes a monitoring unit.

[0290] This monitoring unit can be connected to the third output port of the first optical signal processing component to monitor the optical signal power of the third output port of the first optical signal processing component, or can be connected to the second output port of the first optical signal processing component to monitor the optical signal power of the second output port of the first optical signal processing component. The embodiments of the present application do not limit this.

[0291] Optionally, there can be multiple monitoring units. For example, at the output end 2 of the first optical signal processing component in Figure 8 an optical signal can be output, or a monitoring unit can be connected. The embodiments of the present application do not limit this.

[0292] It should be understood that the first 2×2 directional coupler, the second 2×2 directional coupler, and the first 1×2 multimode interferometer included in at least two power distribution units in the optical waveguide component shown in this exemplary figure 2, in addition to the above Figure 8 shown connection relationship, can also be other possible connection relationships, Figure 8 only as a possible exemplary illustration, and should not limit the embodiments of the present application based on this.Figure 8 New embodiments obtained by reasonable deformation or supplementation of the connection relationships shown all fall within the protection scope of the embodiments of the present application.

[0293] Through the optical waveguide component in the second exemplary embodiment, it is possible to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide component.

[0294] Exemplary three:

[0295] The above at least two power distribution units include: a first 2×2 directional coupler, a second 2×2 directional coupler, and a third 2×2 directional coupler.

[0296] Wherein, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascaded with the second 2×2 directional coupler and the third 2×2 directional coupler in sequence.

[0297] Alternatively, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, one side port of the second 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side ports of the first 2×2 directional coupler and the second 2×2 directional coupler are respectively cascaded with the third 2×2 directional coupler.

[0298] For details, reference can be made to Figure 9 and Figure 10 , Figure 9 and Figure 10 which are the structural schematic diagrams of two optical waveguide components provided by the embodiments of the present application.

[0299] As Figure 9 and Figure 10 shown, the optical waveguide component includes 4 coupling units (coupling unit 1, coupling unit 2, coupling unit 3, coupling unit 4) and a first optical signal processing component.

[0300] For details of the 4 coupling units, reference can be made to the description in the first exemplary embodiment above, and details will not be repeated here.

[0301] The first optical signal processing component has M = 4 first ports and N = 4 second ports.

[0302] Wherein, the first optical signal processing component includes 4 first phase control units (phase control unit 1, phase control unit 2, phase control unit 3, phase control unit 4) and at least two power distribution units (a first 2×2 directional coupler, a second 2×2 directional coupler, a third 2×2 directional coupler).

[0303] The input end of the above-mentioned coupling unit is used to receive the optical signal in free space, and the output end is connected to the input end of the phase control unit through a waveguide. The phase control unit is used to adjust the phase of the transmitted optical signal.

[0304] For the specific description of the phase control unit, reference can be made to the description in the above-mentioned Exemplary One, which will not be elaborated here.

[0305] In Figure 9 , one side port of the above-mentioned first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the above-mentioned first 2×2 directional coupler is cascaded with the above-mentioned second 2×2 directional coupler and the above-mentioned third 2×2 directional coupler in sequence. The output port of the third 2×2 directional coupler is used to output the optical signal.

[0306] In Figure 10 , one side port of the above-mentioned first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, one side port of the above-mentioned second 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the above-mentioned first 2×2 directional coupler and the other side port of the above-mentioned second 2×2 directional coupler are respectively cascaded with the above-mentioned third 2×2 directional coupler. The output port of the third 2×2 directional coupler is used to output the optical signal.

[0307] For the specific description of the above-mentioned directional couplers (the first 2×2 directional coupler, the second 2×2 directional coupler, and the third 2×2 directional coupler), reference can be made to the description of the directional coupler shown in the above Figure 7 , which will not be elaborated here.

[0308] It can be seen from the comparison between the optical waveguide component shown in the above Exemplary One and the optical waveguide component in this Exemplary Three that the difference between the two is that all 1×2 multimode interferometers are replaced by 2×2 directional couplers, and the first optical signal processing component with 4×2 ports becomes the first optical signal processing component with 4×4 ports.

[0309] Optionally, the coupling ratio of the first 2×2 directional coupler can be 0.6≥η1≥0.4, the coupling ratio of the second directional coupler can be 0.6≥η2≥0.4, and the coupling ratio of the third directional coupler can be 0.6≥η2≥0.4.

[0310] At this time, taking Figure 9Taking the optical waveguide component in [[]] as an example, in the above-mentioned first optical signal processing component, the transmittance corresponding to the optical signal transmitted through the phase control unit 1 to the output port of the third 2×2 directional coupler is 0.4 ≤ S11 ≤ 0.6, and the transmittance corresponding to the optical signal transmitted through the phase control unit 2 to the output port of the third 2×2 directional coupler is 0.16 ≤ S21 ≤ 0.36 (i.e., 0.4×0.4 = 0.16, 0.6×0.6 = 0.36). The transmittance corresponding to the optical signal transmitted through the phase control unit 3 to the output port of the third 2×2 directional coupler is 0.064 ≤ S31 ≤ 0.216 (i.e., 0.4×0.4×0.4 = 0.064, 0.6×0.6×0.6 = 0.216). The transmittance corresponding to the optical signal transmitted through the phase control unit 4 to the output port of the third 2×2 directional coupler is 0.064 ≤ S41 ≤ 0.216 (i.e., 0.4×0.4×0.4 = 0.064, 0.6×0.6×0.6 = 0.216).

[0311] Among them, the above-mentioned S11 represents the transmittance corresponding to the optical signal input from the first input port of the first optical signal processing component and output from the first output port. The above-mentioned S21 represents the transmittance corresponding to the optical signal input from the second input port of the first optical signal processing component and output from the first output port. The above-mentioned S31 represents the transmittance corresponding to the optical signal input from the third input port of the first optical signal processing component and output from the first output port. The above-mentioned S41 represents the transmittance corresponding to the optical signal input from the fourth input port of the first optical signal processing component and output from the first output port.

[0312] Optionally, the above Figure 9 and Figure 10 the optical waveguide component in [[]] further includes a monitoring unit.

[0313] The monitoring unit can be connected to the third output port of the first optical signal processing component to monitor the optical signal power of the third output port of the first optical signal processing component, or can be connected to the fourth output port of the first optical signal processing component to monitor the optical signal power of the fourth output port of the first optical signal processing component. The embodiments of the present application do not limit this.

[0314] Optionally, there can be multiple monitoring units. For example, in Figure 9 the output terminals 3 and output port 4 of the first optical signal processing component in [[]] can both be connected to the monitoring unit. The embodiments of the present application do not limit this.

[0315] It should be understood that the first 2×2 directional coupler, the second 2×2 directional coupler, and the third 2×2 directional coupler included in at least two power distribution units in the optical waveguide component shown in this exemplary figure 3, in addition to the connection relationship shown in the above Figure 9 and Figure 10 can also be other possible connection relationships.Figure 9 and Figure 10 As two possible exemplary illustrations only, the embodiments of the present application should not be limited thereby. Based on Figure 9 and Figure 10 Any reasonable deformation or supplement of the connection relationship shown belongs to the protection scope of the embodiments of the present application.

[0316] Through the optical waveguide component in the third exemplary embodiment, the input optical signal can be transmitted to the output port according to any configured transmittance, solving the walk-off problem in the FMCW lidar, and at the same time reducing the number of components required for the optical waveguide component.

[0317] Exemplary Four:

[0318] The above at least two power distribution units include: a first 2×2 directional coupler, a first 1×2 multimode interferometer, a second 1×2 multimode interferometer, and a third 1×2 multimode interferometer.

[0319] Wherein, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascaded with the first 1×2 multimode interferometer, the second 1×2 multimode interferometer, and the third 1×2 multimode interferometer in sequence.

[0320] For details, reference can be made to Figure 11 , Figure 11 which is a schematic structural diagram of an optical waveguide component provided by the embodiments of the present application.

[0321] As Figure 11 shown, the optical waveguide component includes 5 coupling units (coupling unit 1, coupling unit 2, coupling unit 3, coupling unit 4, coupling unit 5) and a first optical signal processing component.

[0322] For details of the 5 coupling units, reference can be made to the description in the first exemplary embodiment above, and details will not be repeated here.

[0323] The first optical signal processing component has M = 5 first ports and N = 2 second ports.

[0324] Wherein, the first optical signal processing component includes 5 first phase control units (phase control unit 1, phase control unit 2, phase control unit 3, phase control unit 4, phase control unit 5) and at least two power distribution units (a first 2×2 directional coupler, a first 1×2 multimode interferometer, a second 1×2 multimode interferometer, and a third 1×2 multimode interferometer).

[0325] The input end of the above coupling unit is used to receive the optical signal in free space, and the output end is connected to the input end of the phase control unit through a waveguide, and the phase control unit is used to adjust the phase of the transmitted optical signal.

[0326] For details of the phase control unit, reference may be made to the description in the above-mentioned Exemplary One, which will not be elaborated here.

[0327] In Figure 11 , one port on one side of the above-mentioned first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other port of the first 2×2 directional coupler is cascaded with the above-mentioned first 1×2 multimode interferometer, second 1×2 multimode interferometer, and third 1×2 multimode interferometer in sequence. The output port of the third 1×2 multimode interferometer is used to output an optical signal.

[0328] For details of the above-mentioned directional coupler (the first 2×2 directional coupler), reference may be made to the description of the directional coupler shown in the above Figure 7 , which will not be elaborated here.

[0329] From the comparison between the optical waveguide component shown in the above Exemplary One and the optical waveguide component in this Exemplary Four, it can be seen that the difference between the two is that: an additional 1×2 multimode interferometer is added, and the first optical signal processing component with a 4×2 port is changed to a first optical signal processing component with a 5×2 port.

[0330] Optionally, for details of the receiving principle of the walk-off spot of the lidar and the beneficial effects during the optical alignment of the monitoring unit in this Exemplary Four, reference may be made to the description in the above Exemplary One, which will not be elaborated here.

[0331] It should be understood that the first 2×2 directional coupler, the first 1×2 multimode interferometer, the second 1×2 multimode interferometer, and the third 1×2 multimode interferometer included in at least two power distribution units in the optical waveguide component shown in this Exemplary Four, in addition to the above Figure 11 shown connection relationship, may also be other possible connection relationships, Figure 11 only as a possible exemplary illustration, and should not be used to limit the embodiments of the present application. Based on Figure 11 the reasonable deformation or supplement of the shown connection relationship, the new embodiments obtained all fall within the protection scope of the embodiments of the present application.

[0332] Through the optical waveguide component in this Exemplary Four, it is possible to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide component.

[0333] Exemplary Five:

[0334] The above at least two power distribution units include: a first adjustable ratio coupler, a second adjustable ratio coupler, and a third adjustable ratio coupler, and the coupling ratio configured by the adjustable ratio coupler is any value.

[0335] Wherein, one port of the first adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, and the other port of the first adjustable ratio coupler is cascaded with the second adjustable ratio coupler and the third adjustable ratio coupler in sequence.

[0336] Alternatively, one port of the first adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, one port of the second adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, and the other ports of the first adjustable ratio coupler and the second adjustable ratio coupler are respectively cascaded with the third adjustable ratio coupler.

[0337] Specifically, reference can be made to Figure 12 and Figure 13 , Figure 12 and Figure 13 which are the structural schematic diagrams of two optical waveguide components provided by the embodiments of the present application.

[0338] As Figure 12 and Figure 13 shown, the optical waveguide component includes 4 coupling units (coupling unit 1, coupling unit 2, coupling unit 3, coupling unit 4) and a first optical signal processing component.

[0339] For the specific description of the 4 coupling units, reference can be made to the description in the above Exemplary One, which will not be elaborated here.

[0340] The first optical signal processing component has M = 4 first ports and N = 4 second ports.

[0341] Wherein, the first optical signal processing component includes 4 first phase control units (phase control unit 1, phase control unit 2, phase control unit 3, phase control unit 4) and at least two power distribution units (the first adjustable ratio coupler, the second adjustable ratio coupler, the third adjustable ratio coupler).

[0342] The input end of the coupling unit is used to receive the optical signal in free space, and the output end is connected to the input end of the phase control unit through a waveguide. The phase control unit is used to adjust the phase of the transmitted optical signal.

[0343] For the specific description of the phase control unit, reference can be made to the description in the above Exemplary One, which will not be elaborated here.

[0344] In Figure 12 , one port of the first adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, the other port of the first adjustable ratio coupler is cascaded with the second adjustable ratio coupler and the third adjustable ratio coupler in sequence, and the output port of the third adjustable ratio coupler is used to output the optical signal.

[0345] InFigure 13 In this case, one port of the first adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, one port of the second adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, the other ports of the first adjustable ratio coupler and the second adjustable ratio coupler are respectively cascaded with the third adjustable ratio coupler, and the output port of the third adjustable ratio coupler is used to output an optical signal.

[0346] Optionally, for the adjustable ratio coupler (the first adjustable ratio coupler, the second adjustable ratio coupler, the third adjustable ratio coupler), reference can be specifically made to Figure 14 , Figure 14 which is a schematic structural diagram of an adjustable ratio coupler provided by an embodiment of the present application.

[0347] As Figure 14 shown, this adjustable ratio coupler has 2 input ports and 2 output ports, and is sequentially cascaded by a 2×2 directional coupler, an adjustable phase control unit, and a 2×2 directional coupler.

[0348] Optionally, the latter 2×2 directional coupler can also be replaced by a 2×2 multimode interferometer, or can also be replaced by a 2×1 multimode interferometer, and the embodiments of the present application do not limit this.

[0349] For example, the adjustable ratio coupler includes at least one of the following:

[0350] Two 2×2 directional couplers and one adjustable phase control unit, and the one adjustable phase control unit is arranged between the two 2×2 directional couplers.

[0351] Or, one 2×2 directional coupler, one adjustable phase control unit and one 2×2 multimode interferometer, and the one adjustable phase control unit is arranged between the one 2×2 directional coupler and the one 2×2 multimode interferometer.

[0352] Or, one 2×2 directional coupler, one adjustable phase control unit and one 2×1 multimode interferometer, and the one adjustable phase control unit is arranged between the one 2×2 directional coupler and the one 2×1 multimode interferometer.

[0353] It can be understood that this adjustable ratio coupler can include the above-mentioned various components and their corresponding connection relationships, so that the required transmittance can be pre-configured according to any application scenario, or the configured transmittance can be adjusted in real time according to the requirements of the application scenario during transmission, so as to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide component.

[0354] As can be seen from the comparison between the optical waveguide component shown in the above Exemplary One and the optical waveguide component in this Exemplary Five, the difference between the two is that the first optical signal processing component with a 4×2 port is changed to a first optical signal processing component with a 4×4 port.

[0355] Through the coupling ratio configured by the adjustable ratio coupler, the port transmittances S11, S21, S31, and S41 can be adjusted.

[0356] For example, by adjusting the adjustable ratio coupler, the transmittance corresponding to the output port 1 of the third adjustable ratio coupler when the optical signal is transmitted through the phase control unit 1 is S11≤0.65, the transmittance corresponding to the output port 1 of the third adjustable ratio coupler when the optical signal is transmitted through the phase control unit 2 is 0.2≤S21≤0.3, the transmittance corresponding to the output port 1 of the third adjustable ratio coupler when the optical signal is transmitted through the phase control unit 3 is 0.05≤S31≤0.20, and the transmittance corresponding to the output port 1 of the third adjustable ratio coupler when the optical signal is transmitted through the phase control unit 4 is 0.01≤S41≤0.20.

[0357] Among them, the above S11 represents the transmittance corresponding to the optical signal input from the first input port of the first optical signal processing component and output from the first output port, the above S21 represents the transmittance corresponding to the optical signal input from the second input port of the first optical signal processing component and output from the first output port, the above S31 represents the transmittance corresponding to the optical signal input from the third input port of the first optical signal processing component and output from the first output port, and the above S41 represents the transmittance corresponding to the optical signal input from the fourth input port of the first optical signal processing component and output from the first output port.

[0358] Optionally, the above Figure 12 and Figure 13 The optical waveguide component in also includes a monitoring unit.

[0359] For the beneficial effects of the monitoring unit during optical alignment and adjustment, please refer to the description in the above Exemplary One for details, which will not be elaborated here.

[0360] It should be understood that the first adjustable ratio coupler, the second adjustable ratio coupler, and the third adjustable ratio coupler included in at least two power distribution units in the optical waveguide component shown in this Exemplary Five, in addition to the connection relationships shown in the above Figure 12 and Figure 13 can also be other possible connection relationships. Figure 12 and Figure 13 Only as two possible exemplary explanations, the embodiments of the present application should not be limited thereby. Based on Figure 12 and Figure 13 New embodiments obtained by reasonable deformation or supplementation of the shown connection relationships all fall within the protection scope of the embodiments of the present application.

[0361] Through the optical waveguide component in this exemplary embodiment 5, the input optical signal can be transmitted to the output port according to any configured transmittance, solving the walk-off problem in the FMCW lidar, and at the same time reducing the number of components required for the optical waveguide component.

[0362] Exemplary embodiment 6:

[0363] The above at least two power distribution units include: at least one phase control unit, a first multimode interferometer having M input ports and M output ports, and a second multimode interferometer having N input ports and N output ports.

[0364] Wherein, one side port of the first multimode interferometer is connected to the first coupling unit or the first phase control unit, and the other side port of the first multimode interferometer is cascaded with the at least one phase control unit and the second multimode interferometer in sequence.

[0365] Specifically, reference can be made to Figure 15 , Figure 15 which is a schematic structural diagram of an optical waveguide component provided by an embodiment of the present application.

[0366] As Figure 15 shown, the optical waveguide component includes 4 coupling units (coupling unit 1, coupling unit 2, coupling unit 3, coupling unit 4) and a first optical signal processing component.

[0367] The specific description of the 4 coupling units can refer to the description in the above exemplary embodiment 1, and will not be repeated here.

[0368] The first optical signal processing component has M = 4 first ports and N = 4 second ports.

[0369] Wherein, the first optical signal processing component includes 4 first phase control units (phase control unit 1, phase control unit 2, phase control unit 3, phase control unit 4) and at least two power distribution units (at least one phase control unit, a first multimode interferometer having M input ports and M output ports, and a second multimode interferometer having N input ports and N output ports), and at least one phase control unit includes phase control unit 5, phase control unit 6, and phase control unit 7.

[0370] The input end of the above coupling unit is used to receive the optical signal in free space, and the output end is connected to the input end of the phase control unit through a waveguide, and the phase control unit is used to adjust the phase of the transmitted optical signal.

[0371] The specific description of the phase control unit can refer to the description in the above exemplary embodiment 1, and will not be repeated here.

[0372] In Figure 15In this case, one port on one side of the first multimode interferometer is connected to the first coupling unit or the first phase control unit, and the other port on the other side of the first multimode interferometer is cascaded and connected to the at least one phase control unit (phase control unit 5, phase control unit 6, phase control unit 7) and the second multimode interferometer in sequence. The output port of the second multimode interferometer is used to output an optical signal.

[0373] It can be seen from the comparison between the optical waveguide component shown in the above exemplary one and the optical waveguide component in this exemplary six that the difference between the two is that the first optical signal processing component with a 4×2 port is changed to the first optical signal processing component with a 4×4 port.

[0374] Optionally, for the reception principle of the walk-off spot of the lidar and the beneficial effects during the optical alignment of the monitoring unit in this exemplary six, reference can be specifically made to the description in the above exemplary one, which will not be elaborated here.

[0375] It should be understood that at least two power distribution units in the optical waveguide component shown in this exemplary six include at least one phase control unit, a first multimode interferometer with M input ports and M output ports, and a second multimode interferometer with N input ports and N output ports. In addition to being the Figure 15 connection relationship shown above, it can also be other possible connection relationships. Figure 15 Only as a possible exemplary illustration, the embodiments of the present application should not be limited thereby. Based on Figure 15 new embodiments obtained by reasonable deformation or supplementation of the shown connection relationship all fall within the protection scope of the embodiments of the present application.

[0376] Through the optical waveguide component in this exemplary six, it is possible to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide component.

[0377] Exemplary seven:

[0378] The at least two power distribution units include: at least one phase control unit, a first star coupler with M input ports and M output ports, and a second star coupler with N input ports and N output ports;

[0379] Among them, one port on one side of the first star coupler is connected to the first coupling unit or the first phase control unit, and the other port on the other side of the first star coupler is cascaded and connected to the at least one phase control unit and the second star coupler in sequence.

[0380] The difference between the optical waveguide component shown in this exemplary seven and the optical waveguide component shown in the above exemplary six is that:

[0381] Replace the first multimode interferometer in the optical waveguide assembly shown in the above Exemplary Six with a first star coupler, and replace the second multimode interferometer in the optical waveguide assembly shown in the above Exemplary Six with a second star coupler.

[0382] Therefore, for the description of the optical waveguide assembly shown in this Exemplary Seven, reference can be made specifically to the description of the optical waveguide assembly shown in the above Exemplary Six, which will not be elaborated here.

[0383] Through the optical waveguide assembly in this Exemplary Seven, it is possible to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide assembly.

[0384] Exemplary Eight:

[0385] The above at least two power distribution units include: a first 2×2 directional coupler, a first Y-branch, and a second Y-branch.

[0386] Among them, one side port of the above first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the above first 2×2 directional coupler is cascaded with the above first Y-branch and the above second Y-branch in sequence.

[0387] The difference between the optical waveguide assembly shown in this Exemplary Seven and the optical waveguide assembly shown in the above Exemplary One is that:

[0388] Replace the first 1×2 multimode interferometer in the optical waveguide assembly shown in the above Exemplary One with a first Y-branch, and replace the second 1×2 multimode interferometer in the optical waveguide assembly shown in the above Exemplary One with a second Y-branch.

[0389] Therefore, for the description of the optical waveguide assembly shown in this Exemplary Eight, reference can be made specifically to the description of the optical waveguide assembly shown in the above Exemplary One, which will not be elaborated here.

[0390] Through the optical waveguide assembly in this Exemplary Eight, it is possible to transmit the input optical signal to the output port according to any configured transmittance, solve the walk-off problem in the FMCW lidar, and at the same time reduce the number of components required for the optical waveguide assembly.

[0391] It should be understood that the above Exemplary One to Exemplary Eight are only used to illustrate the components that the above power distribution unit may include as several possible examples, and this application should not be limited thereby. Any new examples obtained through reasonable deformation, supplement, or combination based on the above Exemplary One to Exemplary Eight all fall within the protection scope of this application.

[0392] In addition, the present application also provides a transceiver device, which includes at least two optical waveguide components as described in any of the above possible embodiments, and the at least two optical waveguide components are arranged off-axis or coaxially.

[0393] Specifically, reference can be made to Figure 16A and Figure 16B , Figure 16A and Figure 16B which are schematic structural diagrams of two transceiver devices provided by the embodiments of the present application.

[0394] As shown in Figure 16A and Figure 16B , taking 4 sets of transmitting antennas (TX1, TX2, TX3, TX4) and 4 sets of receiving antennas (RX1, RX2, RX3, RX4) as an example for illustration, the transmitting antennas and receiving antennas can be composed of the optical waveguide components described in any of the above possible embodiments. Figure 16A In the transceiver device shown in Figure 16B , the transmitting antennas and receiving antennas (i.e., multiple optical waveguide components) are arranged off-axis,

[0395] In the transceiver device shown in

[0396] the transmitting antennas and receiving antennas (i.e., multiple optical waveguide components) are arranged coaxially. Figures 17A to 17C , Figures 17A to 17C which are schematic structural diagrams of several transceiver devices provided by the embodiments of the present application.

[0397] As shown in Figure 17A , it is the structure of one set of transmitting antennas and receiving antennas in the transceiver device shown in the embodiment of the present application. Among them, the receiving antenna is composed of the optical waveguide component shown in the above Example 1.

[0398] As shown in Figure 17B , it is the structure of one set of transmitting antennas and receiving antennas in the transceiver device shown in the embodiment of the present application. Among them, the transmitting antenna is composed of the optical waveguide component shown in the above Example 1.

[0399] As shown in Figure 17C , it is the structure of one set of transmitting antennas and receiving antennas in the transceiver device shown in the embodiment of the present application. Among them, both the transmitting antenna and the receiving antenna are composed of the optical waveguide components shown in the above Example 1.

[0400] It can be understood that the transmitting component and the receiving component in the embodiments of the present application are close to each other, and a collimating optical system can be shared to achieve coaxial transceiver. Compared with the off-axis receiving scheme, the coaxial transceiver can simplify the external optical system, reduce the number of required mirrors, and lower the system complexity and system cost.

[0401] The at least two optical waveguide components included in the transceiver device in the embodiments of the present application are applicable to both signal receiving scenarios and signal transmitting scenarios. They can transmit the input far-distance back optical signal to the output port according to the configured transmittance, so that the back optical signal corresponding to the far-distance target has less loss, while the back optical signal corresponding to the near-distance target has greater loss. Thus, no matter how the position of the back optical signal corresponding to the far-distance target deviates, a certain intensity of the back optical signal can always be received and output, solving the deviation problem in FMCW lidar, and the back optical signals corresponding to the received far-distance target and the near-distance target can be relatively balanced, while reducing the number of components required for the optical waveguide components.

[0402] The present application provides a chip, which includes the optical waveguide component or the transceiver device provided by the present application.

[0403] The present application provides a radar or a radar system, which includes the optical waveguide component or the transceiver device provided by the present application or the above chip.

[0404] In a possible implementation manner, the radar includes but is not limited to lidar, etc.

[0405] In a possible implementation manner, there may be intelligent sensors integrating multiple sensors. When the above intelligent sensors include but are not limited to laser detection functions, etc., the above intelligent sensors can also be referred to as a radar or a radar system.

[0406] Specifically, reference can be made to Figure 18 , Figure 18 which is a schematic diagram of the architecture of a radar provided by the embodiments of the present application.

[0407] As Figure 18 shown, the radar or the radar system includes the optical waveguide component or the transceiver device provided by the present application or the above chip, and specifically may include but is not limited to a laser, a beam splitter, an optical transmitting component, an optical component, a beam scanning component, an optical receiving component, a mixer, a photodetector, a signal processor, a controller).

[0408] The laser outputs a continuously frequency-modulated optical signal that enters a beam splitter. The beam splitter divides the input light into two beams. One beam of light directly enters a mixer. The other beam of light enters an optical transmitting component. After passing through the optical component, it is transmitted to an optical scanning component. After being reflected by an object, a reflected optical signal is formed. The reflected optical signal enters an optical receiving component through the optical component. The optical receiving component outputs light that enters the mixer and is converted into an electrical signal by a photodetector and then enters a signal processor for processing.

[0409] Among them, the laser, the beam splitter, the optical transmitting component, and the optical receiving component can be integrated on an optical chip or assembled on an optical chip by means of mounting.

[0410] This application also provides a terminal device. The terminal device includes the optical waveguide component, the transceiver device, the chip, the radar, or the radar system provided by this application. For example, the terminal device can be a transportation vehicle, such as a vehicle, a truck, an aircraft, a drone, a slow transport vehicle, a spacecraft, or a ship, or other transportation vehicles used in any possible scenarios, or it can also be a surveying and mapping device or other devices that can carry a detection device. One or more optical waveguide components, transceiver devices, chips, radars, or radar systems provided by this application are deployed on the terminal device.

[0411] As described above, it is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of changes or substitutions, which should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claimed rights.

Claims

1. An optical waveguide component, characterized in that, Including: M first coupling units and a first optical signal processing component, the first optical signal processing component having M first ports and N second ports, where M is an integer greater than or equal to 3, N is an integer greater than or equal to 2, and N is less than or equal to M; wherein: The first optical signal processing component includes at least M - 2 first phase control units and at least two power distribution units; The first phase control units are disposed between the first coupling units and the power distribution units, or the first phase control units are disposed between any two of the at least two power distribution units.

2. The optical waveguide component according to claim 1, characterized in that, The optical waveguide component is an optical signal receiving component, the M first ports are used to receive optical signals, and the transmittance corresponding to the optical signals received by the M first ports after being processed by the first optical signal processing component increases along the first direction.

3. The optical waveguide component according to claim 1 or 2, characterized in that The first phase control units are disposed between the first coupling units and the power distribution units, including: The at least M - 2 first phase control units are cascade-connected to the M first coupling units.

4. The optical waveguide component according to any one of claims 1 to 3, characterized in that, The number of layers x formed by cascade-connecting the at least two power distribution units satisfies the following condition: p ≤ x ≤ q; Wherein, x is an integer greater than 1, q is an integer greater than 1 and satisfies the following condition: q = M - 1, p is an integer greater than 1 and satisfies the following condition: 2 p-1 <M ≤ 2 p .

5. The optical waveguide component according to any one of claims 1 to 3, characterized in that, The power distribution unit includes at least one of the following: Directional coupler, multimode interferometer, star coupler, adjustable ratio coupler, Y-branch splitter.

6. The optical waveguide component according to claim 4, characterized in that, The at least two power distribution units include: a first 2×2 directional coupler, a first 1×2 multimode interferometer, a second 1×2 multimode interferometer; Wherein, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascade-connected to the first 1×2 multimode interferometer and the second 1×2 multimode interferometer in sequence.

7. The optical waveguide component according to claim 4, characterized in that, The at least two power distribution units include: a first 2×2 directional coupler, a second 2×2 directional coupler, a first 1×2 multimode interferometer; Wherein, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascade-connected to the second 2×2 directional coupler and the first 1×2 multimode interferometer in sequence.

8. The optical waveguide component according to claim 4, characterized in that, The at least two power distribution units include: a first 2×2 directional coupler, a second 2×2 directional coupler, a third 2×2 directional coupler; Wherein, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascade-connected to the second 2×2 directional coupler and the third 2×2 directional coupler in sequence; Or, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, one side port of the second 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side ports of the first 2×2 directional coupler and the second 2×2 directional coupler are respectively cascade-connected to the third 2×2 directional coupler.

9. The optical waveguide component according to claim 4, wherein The at least two power distribution units include: a first 2×2 directional coupler, a first 1×2 multimode interferometer, a second 1×2 multimode interferometer, and a third 1×2 multimode interferometer; Wherein, one side port of the first 2×2 directional coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first 2×2 directional coupler is cascaded with the first 1×2 multimode interferometer, the second 1×2 multimode interferometer, and the third 1×2 multimode interferometer in sequence.

10. The optical waveguide component according to claim 4, wherein The at least two power distribution units include: a first adjustable ratio coupler, a second adjustable ratio coupler, and a third adjustable ratio coupler, and the coupling ratio configured by the adjustable ratio coupler is any value; Wherein, one side port of the first adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first adjustable ratio coupler is cascaded with the second adjustable ratio coupler and the third adjustable ratio coupler in sequence; Alternatively, one side port of the first adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, one side port of the second adjustable ratio coupler is connected to the first coupling unit or the first phase control unit, and the other side ports of the first adjustable ratio coupler and the second adjustable ratio coupler are respectively cascaded with the third adjustable ratio coupler.

11. The optical waveguide component according to claim 10, wherein The adjustable ratio coupler includes at least one of the following: Two 2×2 directional couplers and an adjustable phase control unit, and the one adjustable phase control unit is arranged between the two 2×2 directional couplers; Alternatively, one 2×2 directional coupler, one adjustable phase control unit, and one 2×2 multimode interferometer, and the one adjustable phase control unit is arranged between the one 2×2 directional coupler and the one 2×2 multimode interferometer; Alternatively, one 2×2 directional coupler, one adjustable phase control unit, and one 2×1 multimode interferometer, and the one adjustable phase control unit is arranged between the one 2×2 directional coupler and the one 2×1 multimode interferometer.

12. The optical waveguide component according to claim 5, wherein The at least two power distribution units include: at least one phase control unit, a first multimode interferometer having M input ports and M output ports, and a second multimode interferometer having N input ports and N output ports; Wherein, one side port of the first multimode interferometer is connected to the first coupling unit or the first phase control unit, and the other side port of the first multimode interferometer is cascaded with the at least one phase control unit and the second multimode interferometer in sequence.

13. The optical waveguide component according to claim 5, characterized in that, The at least two power distribution units include: at least one phase control unit, a first star coupler having M input ports and M output ports, and a second star coupler having N input ports and N output ports; Wherein, one side port of the first star coupler is connected to the first coupling unit or the first phase control unit, and the other side port of the first star coupler is cascaded with the at least one phase control unit and the second star coupler in sequence.

14. The optical waveguide component according to any one of claims 1 to 13, characterized in that, The optical waveguide assembly further includes: A monitoring unit; The monitoring unit is configured to monitor the power of the optical signal in the first optical path from the spatial optical field.

15. The optical waveguide component according to claim 14, characterized in that, The monitoring unit is connected to the first output port of the first optical signal processing component. The first optical path is the optical path in which the near-distance echo optical signal from the spatial optical field sequentially passes through the first coupling unit and the first optical signal processing component and is output from the first output port of the first optical signal processing component.

16. The optical waveguide component according to claim 14, wherein, The monitoring unit is connected to the second output port. The first optical path is the optical path in which the near-distance echo optical signal from the spatial optical field passes through the first coupling unit and is output from the second output port.

17. A transceiver device, characterized in that, The transceiver device includes at least two optical waveguide components as described in any one of claims 1 to 16, and the at least two optical waveguide components are arranged off-axis or coaxially.

18. A chip, characterized in that, The chip includes the optical waveguide component as described in any one of claims 1 to 16, or the transceiver device as described in claim 17.

19. A radar, characterized in that, The radar includes the optical waveguide component as described in any one of claims 1 to 16, or the transceiver device as described in claim 17, or the chip as described in claim 18.

20. A terminal device, characterized in that, The terminal device includes the optical waveguide component as described in any one of claims 1 to 16, or the transceiver device as described in claim 17, or the chip as described in claim 18, or the radar as described in claim 19.

21. A car end, characterized in that, The vehicle end includes the optical waveguide component as described in any one of claims 1 to 16, or the transceiver device as described in claim 17, or the chip as described in claim 18, or the radar as described in claim 19, or the terminal device as described in claim 20.

Images