State-tunable dual-gain optical structure on silicon substrate and lidar system

Abstract

The application provides a silicon substrate state-adjustable double-gain optical structure and a laser radar system, and relates to the technical field of laser radar.The silicon substrate state-adjustable double-gain optical structure comprises a first reflective semiconductor optical amplifier, a second reflective semiconductor optical amplifier, a first phase modulator, a second phase modulator, a first optical coupler, a third phase modulator, a fourth phase modulator, a second optical coupler, a first port and a second port; and the reflected light electric field and the transmitted light electric field are adjusted by adjusting the phase difference between the two reflective semiconductor optical amplifiers.The laser radar system is formed by using multiple silicon substrate state-adjustable double-gain optical structures, a transmitting optical phased array, a receiving optical phased array and a balanced photodetector, the transmitting power of the transmitting optical phased array is flexibly adjusted, multiple reflective semiconductor optical amplifiers are used, the laser radar power is significantly improved, and long-distance detection of the laser radar system based on the optical phased array is realized.

Description

Technical Field

[0001] This invention relates to the field of lidar technology, and more specifically, to a state-tunable dual-gain optical structure on a silicon substrate and a lidar system. Background Technology

[0002] Silicon-based optoelectronic integration technology has been widely and significantly applied in many fields such as optical communication, optical interconnection, and optical sensing. However, the biggest bottleneck in silicon-based optoelectronic integration technology is the inability to directly generate lasers within silicon materials. Various solutions have been proposed to address this issue, with the most suitable currently being the hybrid integration of III-V group luminescent materials and silicon photonic chips to fabricate silicon-based external cavity lasers. These lasers still face many unresolved challenges, such as high-power lasers, wavelength-tunable lasers, and optical amplifiers.

[0003] External cavity lasers are widely used in lidar applications due to their advantages such as tunable wavelength and narrow linewidth. Traditional external cavity lasers typically employ a single gain medium or a simple optical feedback structure, which suffers from limited power output. On one hand, the amplification capability of a single gain medium is limited, making it difficult to achieve high-power laser output; on the other hand, a simple optical feedback structure cannot precisely control the optical field distribution within the laser cavity, resulting in low optical energy utilization and further limiting the laser's power increase.

[0004] In lidar applications, the laser is the core component, and its power directly affects the lidar's detection range, accuracy, and sensitivity. Existing lidar systems use lasers with insufficient power, resulting in weak reflected light signals at long distances. These signals are easily affected by environmental noise, leading to decreased detection accuracy and failing to meet the high-precision detection requirements in complex environments.

[0005] Therefore, there is an urgent need for an external cavity laser that can achieve high power output and precisely adjust the optical field distribution, which is of great significance for improving the performance of lidar systems. Summary of the Invention

[0006] To address the problems in the background art, the present invention provides a state-tunable dual-gain optical structure and laser on a silicon substrate, thereby overcoming the defects of existing lasers.

[0007] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0008] A state-tunable dual-gain optical structure on a silicon substrate, characterized in that it comprises:

[0009] A first reflective semiconductor optical amplifier, a second reflective semiconductor optical amplifier, a first phase modulator, a second phase modulator, a first optical coupler, a third phase modulator, a fourth phase modulator, a second optical coupler, a first port, and a second port.

[0010] The first terminal of the first reflective semiconductor optical amplifier is connected to the first terminal of the first phase modulator, the first terminal of the second reflective semiconductor optical amplifier is connected to the first terminal of the second phase modulator, the second terminals of the first and second phase modulators are respectively connected to the first and second terminals of the first optical coupler, the third and fourth terminals of the first optical coupler are respectively connected to the first terminal of the third phase modulator and the first terminal of the fourth phase modulator, the second terminals of the third and fourth phase modulators are respectively connected to the first and second terminals of the second optical coupler, and the third and fourth terminals of the second optical coupler are respectively connected to the first port and the second port. Incident light enters from the first port, reflected light is output from the first port, and the second port is used to output transmitted light.

[0011] The first phase modulator, the second phase modulator, the first optical coupler, the third phase modulator, the fourth phase modulator, and the second optical coupler are integrated on the same silicon-based chip. The second ends of the first reflective semiconductor optical amplifier and the second reflective semiconductor optical amplifier are both coated with high-reflectivity films. The electric field of the reflected light and the electric field of the transmitted light are adjusted by adjusting the phase difference between the two reflective semiconductor optical amplifiers.

[0012] Preferably, the phase difference between the two reflective semiconductor optical amplifiers With the electric field E of the reflected light Re and the electric field E of the transmitted light Tr The relationship is as follows:

[0013]

[0014] Among them, E In For the incident photoelectric field, r A denoted as the amplification factor of the first reflective semiconductor optical amplifier, i as the imaginary unit, κ as the coupling coefficient between the first and second optical couplers, t as the transmission coefficient between the first and second optical couplers, θ as the phase difference between the third and fourth phase modulators, and r as the gain ratio between the two reflective semiconductor optical amplifiers.

[0015] Preferably, the phase difference between the two reflective semiconductor optical amplifiers is adjusted such that when the ratio of the electric field of the reflected light to the incident electric field is 0, the first port does not output reflected light, and the optical structure is configured as an optical amplifier; when the ratio of the electric field of the reflected light to the incident electric field is greater than 0 and less than 1, the optical structure is configured as a transflector.

[0016] A lidar system includes: a transflector, a transmitting optical phased array, a receiving optical phased array, a balanced photodetector, and a first reflective device. The first port of the transflector is connected to a first end of the first reflective device, the second end of the first reflective device is connected to the transmitting optical phased array, the second port of the transflector is connected to one end of the balanced photodetector, and the other end of the balanced photodetector is connected to the receiving optical phased array. The first reflective device is a wavelength-tunable reflector or a transflector.

[0017] A lidar system includes: two transflectors, a transmitting optical phased array, a receiving optical phased array, a balanced photodetector, and a tunable filter. The first port of the first transflector is connected to the first end of the tunable filter, the second end of the tunable filter is connected to the first port of the second transflector, the second port of the first transflector is connected to the transmitting optical phased array, the second port of the second transflector is connected to one end of the balanced photodetector, and the other end of the balanced photodetector is connected to the receiving optical phased array. The tunable filter has a dual-micro-ring structure.

[0018] Preferably, it further includes an optical amplifier disposed between the second port of the first transflector and the transmitting optical phased array.

[0019] A lidar system includes: two transflectors, two optical amplifiers, a first transmitting optical phased array, a second transmitting optical phased array, an optical beam splitter, a tunable filter, a balanced photodetector, and a receiving optical phased array; wherein, the second port of the first optical amplifier is connected to the first transmitting optical phased array, the first port of the first optical amplifier is connected to one of the multiple output ports of the optical beam splitter, the second port of the second optical amplifier is connected to the input port of the optical beam splitter, the first port of the second optical amplifier is connected to the second port of the first transflector, the first port of the first transflector is connected to the first port of the tunable filter, the second port of the tunable filter is connected to the first port of the second transflector, the second port of the second transflector is connected to one end of the balanced photodetector, and the other end of the balanced photodetector is connected to the receiving optical phased array.

[0020] Preferably, the tunable filter has a dual micro-ring structure.

[0021] The beneficial effects of this invention are as follows:

[0022] (1) By utilizing the interaction between two reflective semiconductor optical amplifiers, and in conjunction with the first and second phase modulators directly connected to them, a unique optical structure can be constructed, which can precisely adjust the phase relationship between the two.

[0023] (2) When the ratio of the reflected photoelectric field to the incident photoelectric field is 0, the optical structure can be configured as an optical amplifier to achieve effective amplification and output of the optical signal; when the ratio is in the range of greater than 0 and less than 1, the optical structure is configured as a semi-transparent and semi-reflective device, which facilitates structural expansion and broadens the application range.

[0024] (3) The reflected and transmitted photoelectric fields are calculated based on the phase difference between the two reflective semiconductor optical amplifiers, so as to realize the flexible adjustment of the ratio of transmitted and reflected light. By precisely controlling the ratio of reflected and transmitted light, the light field distribution in the laser cavity can be optimized and the light energy utilization rate can be improved. This not only further enhances the power stability of the laser, but also allows for flexible adjustment of the light output characteristics according to different application scenarios, such as different weather conditions or detection distance requirements, thereby enhancing the environmental adaptability of the lidar system.

[0025] (4) A semi-transparent and semi-reflective device configured with a state-tunable dual-gain optical structure on a silicon substrate is combined with a reflector to form an external cavity laser for a lidar system. Compared with traditional external cavity lasers, the laser of the present invention can provide a stronger emission source for lidar systems, effectively enhance the detection range and signal strength of lidar, and meet the requirements of long-distance and high-precision detection.

[0026] (5) The invention utilizes a semi-transparent, semi-reflective transducer configured with multiple state-tunable dual-gain optical structures on a silicon substrate, and an optical amplifier configured with selectively connected state-tunable dual-gain optical structures on a silicon substrate. This design exhibits excellent structural compactness and facilitates integration with other components of the lidar system. Compared to traditional, complex high-power lidar systems, this invention, based on a hybrid integrated chip, simplifies the overall structure, reduces system size and weight, and promotes the miniaturization and lightweighting of lidar systems, thus broadening application scenarios. Attached Figure Description

[0027] To facilitate understanding of the invention, it will be described in more detail with reference to the specific embodiments shown in the accompanying drawings. These drawings depict only typical embodiments of the invention and should not be considered as limiting the scope of protection of the invention.

[0028] Figure 1 This is a schematic diagram of the on-chip state-tunable dual-gain optical structure provided in an embodiment of the present invention;

[0029] Figure 2 This is a schematic diagram of phase adjustment of the on-chip adjustable dual-gain optical structure provided in an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of the lidar system provided in an embodiment of the present invention;

[0031] Figure 4 This is another structural schematic diagram of a lidar system provided in another embodiment of the present invention;

[0032] Figure 5 This is another structural schematic diagram of a lidar system provided in another embodiment of the present invention;

[0033] Figure 6 This is another structural schematic diagram of a lidar system provided in another embodiment of the present invention;

[0034] Figure 7 This is another schematic diagram of a lidar system provided in another embodiment of the present invention.

[0035] Figure label:

[0036] 100 - On-chip state-tunable dual-gain optical structure, 110 - Reflective semiconductor optical amplifier pair, 121a - First phase modulator, 121b - Second phase modulator, 123a - First optical coupler, 122a - Third phase modulator, 122b - Fourth phase modulator, 123b - Second optical coupler, 120 - Silicon-based chip, 100 - R - Semi-transparent and semi-reflective, 100 - A - Optical amplifier, 200 - First reflective device, 301 - Transmitting optical phased array, 302 - Receiving optical phased array, 400 - Balanced photodetector, 500 - Tunable filter, 600 - Optical beam splitter. Detailed Implementation

[0037] Embodiments of the present invention are described below with reference to the accompanying drawings to enable those skilled in the art to better understand and implement the invention. However, the listed embodiments are not intended to limit the invention. Unless otherwise specified, the following embodiments and their technical features can be combined with each other, wherein identical components are denoted by the same reference numerals. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0038] This invention proposes a state-tunable dual-gain optical structure on a silicon substrate. Please refer to [reference needed]. Figure 1 , Figure 1 This is a schematic diagram of the state-tunable dual-gain optical structure on a silicon substrate provided in an embodiment of the present invention.

[0039] See Figure 1In this embodiment of the invention, the on-chip adjustable dual-gain optical structure 100 includes a pair of reflective semiconductor optical amplifiers 110 composed of two reflective semiconductor optical amplifiers, a first phase modulator 121a, a second phase modulator 121b, a first optical coupler 123a, a third phase modulator 122a, a fourth phase modulator 122b, and a second optical coupler 123b; the first ends of the two reflective semiconductor optical amplifiers are respectively connected to the first ends of the first phase modulator 121a and the second phase modulator 121b, and the second ends of the first phase modulator 121a and the second phase modulator 121b are connected separately. The first and second ends of the first optical coupler 123a are connected separately. The third and fourth ends of the first optical coupler 123a are connected to the first ends of the third phase modulator 122a and the fourth phase modulator 122b, respectively. The second ends of the third phase modulator 122a and the fourth phase modulator 122b are connected to the first and second ends of the second optical coupler 123b, respectively. The third and fourth ends of the second optical coupler 123b are connected to the first port and the second port, respectively. Incident light In enters from the first port, reflected light Re exits from the first port, and the second port is used to output transmitted light Tr. The first phase modulator 121a, the second phase modulator 121b, the first optical coupler 123a, the third phase modulator 122a, the fourth phase modulator 122b, and the second optical coupler 123b are integrated on the same silicon-based chip, and the reflective semiconductor optical amplifier 110 is integrated on another chip.

[0040] After the incident light In enters from the first port, it is first split by the second optical coupler 123b, then phase-modulated by the third phase modulator 122a and the fourth phase modulator 122b, then combined by the first optical coupler 123a, and then enters the reflective semiconductor optical amplifier pair 110 composed of two reflective semiconductor optical amplifiers through the first phase modulator 121a and the second phase modulator 121b. The ends of the two reflective semiconductor optical amplifiers away from the first phase modulator 121a and the second phase modulator 121b are coated with high-reflectivity films. The reflected light then passes through the first phase modulator 121a and the second phase modulator 121b for phase modulation, the first optical coupler 123a, the third phase modulator 122a and the fourth phase modulator 122b for phase modulation, and finally outputs the reflected light Re and the transmitted light Tr after passing through the second optical coupler 123b.

[0041] Figure 2 This is a schematic diagram of phase adjustment of the on-chip tunable dual-gain optical structure provided in an embodiment of the present invention. See [link / reference]. Figure 2 There is a phase difference between the two reflective semiconductor optical amplifiers. By directly connecting the first phase modulator 121a and the second phase modulator 121b, a unique optical structure is constructed, which can precisely adjust the phase relationship between the two reflective semiconductor optical amplifiers; the electric field E of the reflected light Re and the electric field E of the transmitted lightTr The relationship is as follows:

[0042]

[0043] Among them, E In For the incident photoelectric field, r A Let be the amplification factor of the reflective semiconductor optical amplifier to one of the reflective semiconductor optical amplifiers in 110, i be the imaginary unit, κ be the coupling coefficient of the first optical coupler 123a and the second optical coupler 123b, t be the transmission coefficient of the first optical coupler 123a and the second optical coupler 123b, θ be the phase difference between the third phase modulator 122a and the fourth phase modulator 122b, and r be the gain ratio between the two reflective semiconductor optical amplifiers.

[0044] Therefore, by adjusting the phase difference between the two reflective semiconductor optical amplifiers, the distribution ratio between reflected and transmitted light can be adjusted. When the ratio of the reflected photoelectric field to the incident photoelectric field is 0, the first port does not output reflected light; at this time, there is only transmission and no reflection, which is equivalent to an optical amplifier. The corresponding optical structure is configured as an optical amplifier, denoted as 100-A. When the ratio of the reflected photoelectric field to the incident photoelectric field is greater than 0 and less than 1, the optical structure is configured as a semi-transparent and semi-reflective amplifier, denoted as 100-R.

[0045] It is worth noting that the gain ratio between the two reflective semiconductor optical amplifiers, the splitting ratio of the first and second optical couplers, and the phase difference between the third and fourth phase modulators can be set as constants. Based on the phase difference between the two reflective semiconductor optical amplifiers, the reflected and transmitted photoelectric fields can be calculated, allowing for flexible adjustment of the ratio of transmitted to reflected light. Alternatively, the ratio of reflected to transmitted light can be adjusted based on the phase and gain ratio between the two reflective semiconductor optical amplifiers, the splitting ratio of the first and second optical couplers, and the phase difference between the third and fourth phase modulators, achieving flexible adjustment of the ratio of transmitted to reflected light. When the ratio of the reflected photoelectric field to the incident photoelectric field is 0, the optical structure can be configured as an optical amplifier to achieve effective amplification and output of the optical signal; when the ratio is greater than 0 and less than 1, the optical structure is configured as a transflector, facilitating structural expansion and broadening the application range.

[0046] Figure 3 This is a schematic diagram of the lidar system provided in an embodiment of the present invention. See also: Figure 3A lidar system includes: a transflector 100-R, a transmitting optical phased array 301, a receiving optical phased array 302, a balanced photodetector 400, and a first reflector 200. The first port of the transflector 100-R is connected to the first end of the first reflector 200, the second end of the first reflector 200 is connected to the transmitting optical phased array 301, the second port of the transflector 100-R is connected to one end of the balanced photodetector 400, and the other end of the balanced photodetector 400 is connected to the receiving optical phased array 302. The first reflector 200 is a wavelength-tunable reflector or a transflector.

[0047] Incident light is input to the first port of the transflector 100-R. After entering the optical structure and being reflected by two reflective semiconductor optical amplifiers, the incident light is finally output as reflected light at the first port and transmitted light at the second port. The reflected light output from the first port can be reflected by the first reflector 200, meaning that a portion of the reflected light from the first reflector 200 returns to the transflector 100-R as incident light, forming the resonant cavity of the laser through multiple reflections. The first reflector 200 is a wavelength-tunable reflector or a half-reflector. The other portion of the reflected light from the first reflector 200 is output to the transmitting optical phased array 301, where it is emitted outward into space and received by the receiving optical phased array 302. Both the emitted and received signal light enter the balanced photodetector 400.

[0048] Figure 4 This is another structural schematic diagram of a lidar provided in another embodiment of the present invention, see [link / reference]. Figure 4 A lidar system includes: two transflectors 100-R, a transmitting optical phased array 301, a receiving optical phased array 302, a balanced photodetector 400, and a tunable filter 500. The first port of the first transflector is connected to the first end of the tunable filter 500, the second end of the tunable filter 500 is connected to the first port of the second transflector, the second port of the first transflector is connected to the transmitting optical phased array 301, the second port of the second transflector is connected to one end of the balanced photodetector 400, and the other end of the balanced photodetector 400 is connected to the receiving optical phased array 302. The tunable filter 500 has a dual-micro-ring structure.

[0049] Figure 5 This is another schematic diagram of a lidar system provided in another embodiment of the present invention, see [link / reference]. Figure 5It also includes an optical amplifier 100-A, which is positioned between the second port of the first transflector and the transmitting optical phased array 301. The optical amplifier effectively increases the emitted laser power. Due to the increased emitted power of the lidar system, the intensity of the reflected light signal is enhanced, enabling the system to acquire three-dimensional information of the target object more clearly, reducing the impact of environmental noise on the detection results, and effectively improving detection accuracy and reliability.

[0050] Figure 6 This is another schematic diagram of a lidar system provided in another embodiment of the present invention, see [link / reference]. Figure 6 The lidar system includes: two transflectors 100-R, two optical amplifiers 100-A, a transmitting optical phased array 301, two tunable filters 500, a balanced photodetector 400, and a receiving optical phased array 302. Figure 6 exist Figure 5 Based on this, it is equivalent to inserting an optical amplifier inside the external cavity laser, which significantly increases the emitted laser power.

[0051] Figure 7 This is another schematic diagram of a lidar system provided in another embodiment of the present invention, see [link / reference]. Figure 7 The lidar system includes: two transflector-reflector units 100-R, two optical amplifiers 100-A, a first transmitting optical phased array, a second transmitting optical phased array, an optical beam splitter 600, a tunable filter 500, a balanced photodetector 400, and a receiving optical phased array. The second port of the first optical amplifier is connected to the first transmitting optical phased array; the first port of the first optical amplifier is connected to one of the multiple outputs of the optical beam splitter 600; the second port of the second optical amplifier is connected to the input of the optical beam splitter; the first port of the second optical amplifier is connected to the second port of the first transflector-reflector unit; the first port of the first transflector-reflector unit is connected to the first terminal of the tunable filter 500; the second terminal of the tunable filter 500 is connected to the first port of the second transflector-reflector unit; the second port of the second transflector-reflector unit is connected to one end of the balanced photodetector 400; and the other end of the balanced photodetector 400 is connected to the receiving optical phased array. The tunable filter 500 has a dual-micro-ring structure.

[0052] It is worth noting that this invention significantly improves the power amplification capability of the external cavity laser by setting a dual-gain optical structure. Compared with traditional single-gain external cavity lasers, the laser of this invention can achieve higher power output, providing a stronger emission source for lidar, effectively enhancing the detection range and signal strength of lidar, and meeting the requirements of long-distance, high-precision detection. The unique dual-gain optical structure allows for flexible adjustment of the reflected light ratio and the transmitted light ratio. By precisely controlling the ratio of reflected light to transmitted light, the light field distribution within the laser cavity can be optimized, improving the light energy utilization rate. This not only further enhances the power stability of the laser but also allows for flexible adjustment of the light output characteristics according to different application scenarios, such as different weather conditions or detection distance requirements, enhancing the environmental adaptability of the laser and lidar. The lidar system built based on the high-power laser of this invention achieves a significant improvement in detection performance. Due to the increased emission power of the lidar system, the intensity of the reflected light signal is enhanced, enabling the system to acquire the three-dimensional information of the target object more clearly, reducing the impact of environmental noise on the detection results, and effectively improving detection accuracy and reliability. Even in complex environments, such as dusty conditions or rainy / foggy weather, this lidar can still operate stably and accurately identify targets, providing more reliable technical support for fields such as autonomous driving and environmental monitoring. This invention achieves high power and light ratio adjustment while maintaining a compact structure, facilitating integration with other components of a lidar system. Compared to traditional complex high-power lidar systems, this invention simplifies the overall structure, reduces system size and weight, promotes the miniaturization and lightweighting of lidar, and broadens its application scenarios.

[0053] The various embodiments in this invention are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section.

[0054] The embodiments described above are merely preferred embodiments of the present invention. The terms "in one embodiment," "in another embodiment," "in yet another embodiment," or "in still another embodiment" used in this specification all refer to one or more of the same or different embodiments according to this disclosure. Ordinary variations and substitutions made by those skilled in the art within the scope of the present invention should be included within the protection scope of the present invention.

Claims

1. A state-tunable dual-gain optical structure on a silicon substrate, characterized in that, include: A first reflective semiconductor optical amplifier, a second reflective semiconductor optical amplifier, a first phase modulator, a second phase modulator, a first optical coupler, a third phase modulator, a fourth phase modulator, a second optical coupler, a first port, and a second port. The first terminal of the first reflective semiconductor optical amplifier is connected to the first terminal of the first phase modulator, the first terminal of the second reflective semiconductor optical amplifier is connected to the first terminal of the second phase modulator, the second terminals of the first and second phase modulators are respectively connected to the first and second terminals of the first optical coupler, the third and fourth terminals of the first optical coupler are respectively connected to the first terminal of the third phase modulator and the first terminal of the fourth phase modulator, the second terminals of the third and fourth phase modulators are respectively connected to the first and second terminals of the second optical coupler, and the third and fourth terminals of the second optical coupler are respectively connected to the first port and the second port. Incident light enters from the first port, reflected light is output from the first port, and the second port is used to output transmitted light. The first phase modulator, the second phase modulator, the first optical coupler, the third phase modulator, the fourth phase modulator, and the second optical coupler are integrated on the same silicon-based chip. The second ends of the first reflective semiconductor optical amplifier and the second reflective semiconductor optical amplifier are both coated with high-reflectivity films. The electric field of the reflected light and the electric field of the transmitted light are adjusted by adjusting the phase difference between the two reflective semiconductor optical amplifiers.

2. The on-chip tunable dual-gain optical structure according to claim 1, characterized in that, The phase difference between the two reflective semiconductor optical amplifiers With the electric field E of the reflected light Re and the electric field E of the transmitted light Tr The relationship is as follows: Among them, E In For the incident photoelectric field, r A denoted as the amplification factor of the first reflective semiconductor optical amplifier, i as the imaginary unit, κ as the coupling coefficient between the first and second optical couplers, t as the transmission coefficient between the first and second optical couplers, θ as the phase difference between the third and fourth phase modulators, and r as the gain ratio between the two reflective semiconductor optical amplifiers.

3. The on-chip tunable dual-gain optical structure according to claim 2, characterized in that, The phase difference between the two reflective semiconductor optical amplifiers is adjusted. When the ratio of the electric field of the reflected light to the incident electric field is 0, the first port does not output reflected light, and the optical structure is configured as an optical amplifier. When the ratio of the electric field of the reflected light to the incident electric field is greater than 0 and less than 1, the optical structure is configured as a transflector.

4. A lidar system, characterized in that, include: A transflector as described in claim 3 comprises a transmitting optical phased array, a receiving optical phased array, a balanced photodetector, and a first reflecting device, wherein the first port of the transflector is connected to a first end of the first reflecting device, the second end of the first reflecting device is connected to the transmitting optical phased array, the second port of the transflector is connected to one end of the balanced photodetector, and the other end of the balanced photodetector is connected to the receiving optical phased array; wherein the first reflecting device is a wavelength-tunable reflector or a transflector.

5. A lidar system, characterized in that, include: Two transflector-reflector devices as described in claim 3, comprising a transmitting optical phased array, a receiving optical phased array, a balanced photodetector, and a tunable filter, wherein the first port of the first transflector-reflector is connected to the first end of the tunable filter, the second end of the tunable filter is connected to the first port of the second transflector-reflector, the second port of the first transflector-reflector is connected to the transmitting optical phased array, the second port of the second transflector-reflector is connected to one end of the balanced photodetector, and the other end of the balanced photodetector is connected to the receiving optical phased array; wherein the tunable filter has a dual micro-ring structure.

6. The lidar system according to claim 5, characterized in that, It also includes an optical amplifier as described in claim 3, the optical amplifier being disposed between the second port of the first transflector and the transmitting optical phased array.

7. A lidar system, characterized in that, include: The system comprises two transflector-reflector units as described in claim 3, two optical amplifiers as described in claim 3, a first transmitting optical phased array, a second transmitting optical phased array, an optical beam splitter, a tunable filter, a balanced photodetector, and a receiving optical phased array; wherein the second port of the first optical amplifier is connected to the first transmitting optical phased array, the first port of the first optical amplifier is connected to one of the multiple output ports of the optical beam splitter, the second port of the second optical amplifier is connected to the input port of the optical beam splitter, the first port of the second optical amplifier is connected to the second port of the first transflector-reflector unit, the first port of the first transflector-reflector unit is connected to the first port of the tunable filter, the second port of the tunable filter is connected to the first port of the second transflector-reflector unit, the second port of the second transflector-reflector unit is connected to one end of the balanced photodetector, and the other end of the balanced photodetector is connected to the receiving optical phased array.

8. The lidar system according to claim 7, characterized in that, The tunable filter has a dual micro-ring structure.

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