CN111551914B - Optical phased array device, lidar and detection method based on lidar - Google Patents

Abstract

The invention provides an optical phase control array device, a laser radar and a detection method based on the laser radar, wherein the optical phase control array device comprises the following components: the system comprises an optical switch, an electro-optical intensity modulator, a power distribution network, an amplitude consistency network and a light-operated phased array. The optical switch is used for controlling and receiving optical signals in different modes, and the electro-optical intensity modulator is connected with the optical switch and used for controlling the intensity of the optical signals. The power division network is connected with the electro-optical intensity modulator and used for distributing the optical signals to the plurality of sub-channels. The amplitude consistency network is connected with the power distribution network and used for detecting and adjusting the optical power of the optical signals in each sub-channel. The optical phased array device integrates the electro-optical intensity modulator, the optical switch and the optical control phased array into a chip, so that the integration of measurement and communication is realized.

Description

Optical phased array device, lidar and detection method based on lidar

technical field

The invention relates to the technical field of optoelectronic devices, in particular to an optical phased array device, a laser radar and a detection method based on the laser radar.

Background technique

Optically controlled phased array is the key component of laser radar beamforming. The integration of laser measurement and communication is an important direction for the development of the lidar system in the future. The integrated laser measurement and communication radar is composed of a laser source, a modulator, a beam forming device, a beam scanning device and a detection device, among which the modulator and the beam scanning device are among them. core device.

In the related art, the beam scanning device and the modulation device are separate, that is, the beam scanning function and the communication function need to be implemented by two systems, resulting in the defects of large size, high power consumption and long function switching time.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to solve the defects in the related art that the discrete setting of the beam scanning device and the modulator leads to the large volume, high power consumption and long function switching time of the laser radar device. The invention provides an optical phased array device, a laser radar and a detection method based on the laser radar.

An optical phased array device according to an embodiment of the present invention includes:

Optical switch, used to control and receive light source signals of different modes;

an electro-optical intensity modulator, connected to the optical switch, for modulating the intensity of the optical signal;

a power division network, connected to the electro-optical intensity modulator, for distributing the optical signal to a plurality of sub-channels;

an amplitude consistency network, connected to the power division network, for detecting and adjusting the optical power of the optical signal in each of the sub-channels;

An optically controlled phased array, the optically controlled phased array includes a plurality of electro-optical phase shifters, and each of the sub-channels is provided with the electro-optical phase shifter for adjusting the optical signals in the sub-channels phase.

According to the optical phased array device of the embodiment of the present invention, in order to solve the defects of large volume, heavy weight and slow scanning of the existing integrated technical solution of measurement, control and communication, and the defect that the existing phased array device does not have the function of communication measurement. The phased array device of the invention integrates the electro-optical intensity modulator, the optical switch and the optically controlled phased array in one chip, realizes the integration of measurement and communication, and breaks through the high integration of long-distance laser communication and medium-distance high-precision ranging. The technical problem of miniaturized laser payload optical-mechanical integration.

In addition, in order to solve the problem of inconsistent output amplitudes of each sub-channel of the optically controlled phased array caused by uneven light splitting caused by the chip manufacturing process error, it is necessary to avoid high grating lobe level and beam pointing deviation. In the present invention, an amplitude consistency network is added to the front end of the optically controlled phased array, which effectively ensures the consistency of the optical power in each sub-channel.

According to some embodiments of the present invention, the optical switch is a 2×2 Mach-Zehnder interferometer, comprising two transmission arms and a first phase shifter disposed on at least one of the transmission arms, the first shifter The phaser is used to adjust the phase difference of the optical signals in the two transmission arms, so as to control to receive the light source signals of different modes.

In some embodiments of the present invention, the first phase shifter is a carrier injection type PIN structure or a carrier depletion type PN structure.

According to some embodiments of the present invention, the first phase shifter adopts an electro-optical first phase shifter, and the electro-optical first phase shifter utilizes the carrier dispersion effect of the waveguide to control the two transmission arms. The phase difference of the optical signal.

In some embodiments of the present invention, the magnitude-consistent network includes:

a photodetector, the photodetector is used to detect the optical power of the optical signal in each of the sub-channels;

a directional coupler for adjusting the proportion of the optical signal input to the photodetector in each of the sub-channels;

The adjustable attenuator is used to adjust the optical power of the optical signal in each of the sub-channels according to the optical power of the optical signal in each of the sub-channels.

According to some embodiments of the present invention, the optical switch is used to control receiving continuous laser or pulsed laser.

In some embodiments of the present invention, the optical phased array device is a silicon-based optical phased array device, and the silicon-based optical phased array device is prepared by using a silicon-on-insulator wafer.

A lidar according to an embodiment of the present invention includes: the optical phased array device described above.

The laser radar according to the embodiment of the present invention adopts a silicon-based optical waveguide phased array device integrating measurement and communication, which solves the problem of high-speed space communication and beam scanning splitting, and uses a chip to integrate the modulator and the phased array. Moreover, by setting the amplitude consistency network, the problem that the optical output amplitude of each sub-channel caused by the unbalanced power distribution of the phased array and the optical loss caused by the carrier absorption effect is solved, and the offset of the beam pointing is reduced and reduced. the level of the grating lobe.

According to a detection method based on a lidar according to an embodiment of the present invention, the detection method adopts the lidar as described above, and the method includes:

Controlling receiving continuous laser light through the optical switch;

The optical power of the optical signal in each sub-channel is detected by the amplitude consistency network, and the optical power of the optical signal in each of the sub-channels is adjusted based on the optical power of the optical signal in each of the sub-channels, so as to making the optical power in each of the sub-channels consistent;

Start the detection function of the lidar, and control the receiving pulse laser through the optical switch;

The phase of the received pulsed laser light in each of the sub-channels is adjusted by the optical phased array, and the output forms a scanning beam, so as to scan and detect the target.

According to the detection method based on lidar according to the embodiment of the present invention, a silicon-based optical waveguide phased array device integrating measurement and communication is adopted, and the unbalanced power distribution and carrier absorption of the phased array can be solved by setting an amplitude consistency network. The problem of inconsistency of the optical output amplitude of each sub-channel caused by the optical loss caused by the effect reduces the offset of the beam pointing and the level of the grating lobe.

According to some embodiments of the present invention, the method further comprises:

After scanning and detecting the target to obtain the position of the target, the optical switch controls to receive continuous laser light;

The intensity of the continuous laser is modulated by the electro-optical intensity modulator and a communication signal is generated and sent to the target.

Description of drawings

FIG. 1 is a schematic diagram of a partial structure of a lidar system in the related art;

2 is a schematic structural diagram of an optical phased array device in the related art;

3 is a schematic structural diagram of an optical phased array device according to an embodiment of the present invention;

4 is a schematic structural diagram of an optical switch of an optical phased array device according to a first embodiment of the present invention;

5 is a schematic structural diagram of a phase shifter with a PIN structure according to an embodiment of the present invention;

6 is a schematic structural diagram of a phase shifter with a PN structure according to an embodiment of the present invention;

7 is a schematic structural diagram of an optical switch of an optical phased array device according to a second embodiment of the present invention;

8 is a schematic structural diagram of an electro-optical intensity modulator according to a first embodiment of the present invention;

9 is a schematic structural diagram of an electro-optical intensity modulator according to a second embodiment of the present invention;

FIG. 10 is a schematic structural diagram of an optical power divider according to an embodiment of the present invention.

Detailed ways

In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose, the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

Due to its high frequency, good directionality, and energy concentration, light as a new carrier in aerospace application systems has the following advantages: the narrow frequency spectrum enables high measurement resolution and high measurement accuracy; It has a higher data transmission rate; the characteristics of energy concentration make it work farther; the emission angle of the laser beam is extremely narrow, usually at the milli-arc level or even the micro-arc level. The anti-interference ability of the laser carrier is very high. confidentiality and security.

With the continuous high-intensity investment and research and development at home and abroad in recent years, laser technology has become more and more mature in the field of aerospace applications. Laser ranging, laser imaging, laser communication, laser Doppler and other technologies have typical applications, such as GLAS measurement. GROHE, MOLA altimeter, RVS laser rendezvous and docking sensor, LLCD optical communication system, SSLS laser imaging system, LIST laser mapping system, ALADIN global laser wind measurement system, etc. Among them, laser unified measurement and control technology refers to the use of laser means to realize high-speed laser data transmission and high-precision laser measurement and control between space station-GEO, space station-LEO, and space station-ground, providing technical support for the construction of future space station information ports. Due to the limitations of application scenarios, no relevant application reports have been reported for the integrated technology of communication, imaging and ranging, but there is no technically unbreakable bottleneck. There are mature solutions for inheritance.

As shown in Figure 1, in the related art, the lidar system mainly consists of common aperture optics and two-dimensional scanning system, ATP system, beacon light system, transmitting and receiving system, two-axis scanning system, light source, temperature control, active detection system , imaging processing subsystem and comprehensive information processing and control subsystem.

Among them, the transmitter uses 1550nm and 1064nm fiber lasers as light sources, the 1550nm band is used for laser communication, and the 1065nm band is used for short-range measurement and control and high-speed scanning imaging. The reception adopts the detection method in which the unit APD and the array APD coexist. The communication unit APD realizes the reception of communication light and information acquisition. The array 32×32 array detector is used for measurement, and the scanning system adopts the form of a turntable and a swing mirror.

The disadvantage of the above technical solution is that the system is composed of both a space optical communication system and a laser measurement and control system, and is constructed by discrete components. The inherent defect of the system composed of discrete devices is that the volume and weight of the system are large, which does not meet the requirements of the system for miniaturization and integration of equipment in manned spaceflight applications. In order to achieve fast laser measurement imaging, the scanning rate needs to be in the order of microseconds. The rotation speed achieved by the current turntable and the swing mirror obviously cannot meet the requirements, resulting in too long imaging time.

保证相邻通道差为

可以使用光栅耦合器作为天线实现波导中光耦合到自由空间中，各阵列输出光在空间中合成主波束，通过控制

的大小来实现主波束指向的偏转。In addition, as shown in FIG. 2 , in the related art, the light source is input to each optical phase control channel through an optical power distribution network. The optical power distribution network can be implemented by cascading 1×2 power dividers. Each channel is provided with an electro-optical phase shifter, and by controlling each phase shifter, the phase values of each channel are respectively

The difference between adjacent channels is guaranteed to be

The grating coupler can be used as an antenna to realize the coupling of light in the waveguide into the free space, and the output light of each array is synthesized into the main beam in space, and by controlling

size to achieve the deflection of the main beam pointing.

The above technical solutions have the following defects: due to the manufacturing process error of the basic power division unit, there will always be spectroscopic inhomogeneity and initial phase difference, and the more cascades, the greater the deviation, resulting in different channel amplitudes, grating lobes. Level up. Moreover, it does not have the function of space optical communication.

As shown in FIG. 3 , an optical phased array device according to an embodiment of the present invention includes: an optical switch, an electro-optical intensity modulator, a power division network, an amplitude consistency network, and an optically controlled phased array.

Specifically, the optical switch is used to control the reception of light source signals of different modes. As shown in Figure 3, the optical phased array can be connected to the CW laser and the pulsed laser through the optical switch, and the optical switch can control the connection with the CW laser, disconnect from the pulsed laser, or control the optical switch to disconnect from the CW laser , connected with the pulse laser. Thus, the light switch can be controlled to receive light source signals of different modes.

The electro-optical intensity modulator is connected with the optical switch and is used for modulating the intensity of the optical signal. It should be noted that when the lidar performs the communication function, it can control the received continuous laser light through the optical switch, and modulate the intensity of the received continuous laser light through the electro-optical intensity modulator.

The power division network is connected to the electro-optical intensity modulator for distributing the optical signal into a plurality of sub-channels. The amplitude consistency network is connected with the power division network for detecting and adjusting the optical power of the optical signal in each sub-channel. The optically controlled phased array includes a plurality of electro-optical phase shifters, and each sub-channel is provided with an electro-optical phase shifter for adjusting the phase of the optical signal in the sub-channel.

According to the optical phased array device of the embodiment of the present invention, in order to solve the defects of large volume, heavy weight and slow scanning of the existing integrated technical solution of measurement, control and communication, and the defect that the existing phased array device does not have the function of communication measurement. The phased array device of the invention integrates the electro-optical intensity modulator, the optical switch and the optically controlled phased array in one chip, realizes the integration of measurement and communication, and breaks through the high integration of long-distance laser communication and medium-distance high-precision ranging. The technical problem of miniaturized laser payload optical-mechanical integration.

In addition, in order to solve the problem of inconsistent output amplitudes of each sub-channel of the optically controlled phased array caused by uneven light splitting caused by the chip manufacturing process error, it is necessary to avoid high grating lobe level and beam pointing deviation. In the present invention, an amplitude consistency network is added to the front end of the optically controlled phased array, which effectively ensures the consistency of the optical power in each sub-channel.

According to some embodiments of the present invention, as shown in FIG. 4 , the optical switch is a 2×2 Mach-Zehnder interference instrument, comprising two transmission arms and a first phase shifter disposed on at least one transmission arm. The phaser is used to adjust the phase difference of the optical signals in the two transmission arms to control the reception of optical signals of different modes.

In some embodiments of the present invention, as shown in FIG. 5 and FIG. 6 , the first phase shifter is a carrier injection type PIN structure or a carrier depletion type PN structure. That is to say, the first phase shifter may adopt the carrier injection type PIN structure shown in FIG. 5 ; the first phase shifter may also adopt the carrier depletion type PN structure shown in FIG. 6 .

According to some embodiments of the present invention, the first phase shifter adopts an electro-optical first phase shifter, and the electro-optical first phase shifter utilizes the carrier dispersion effect of the waveguide to control the phase difference of the optical signals in the two transmission arms.

In some embodiments of the invention, the amplitude consistency network includes a photodetector, a directional coupler, and an adjustable attenuator.

Among them, the photodetector is used to detect the optical power of the optical signal in each sub-channel. The directional coupler is used to adjust the proportion of the optical signal input to the photodetector in each sub-channel. The adjustable attenuator is used to adjust the optical power of the optical signal in each sub-channel according to the optical power of the optical signal in each sub-channel.

In some embodiments of the present invention, the optical phased array device is a silicon-based optical phased array device, and the silicon-based optical phased array device is prepared by using a silicon-on-insulator wafer.

A lidar according to an embodiment of the present invention includes: the optical phased array device described above.

The laser radar according to the embodiment of the present invention adopts a silicon-based optical waveguide phased array device integrating measurement and communication, which solves the problem of high-speed space communication and beam scanning splitting, and uses a chip to integrate the modulator and the phased array. Moreover, by setting the amplitude consistency network, the problem that the optical output amplitude of each sub-channel caused by the unbalanced power distribution of the phased array and the optical loss caused by the carrier absorption effect is solved, and the offset of the beam pointing is reduced and reduced. the level of the grating lobe.

According to the detection method based on lidar according to the embodiment of the present invention, the detection method adopts the above lidar, and the method includes:

Receive continuous laser through optical switch control;

The optical power of the optical signal in each sub-channel is detected through the amplitude consistency network, and the optical power of the optical signal in each sub-channel is adjusted based on the optical power of the optical signal in each sub-channel, so that the optical power in each sub-channel consistent;

Start the detection function of the lidar, and receive the pulsed laser through the optical switch control;

The phase of the received pulsed laser light in each sub-channel is adjusted by the optical phased array, and the output forms a scanning beam to scan and detect the target.

According to the detection method based on lidar according to the embodiment of the present invention, a silicon-based optical waveguide phased array device integrating measurement and communication is adopted, and the unbalanced power distribution and carrier absorption of the phased array can be solved by setting an amplitude consistency network. The problem of inconsistency of the optical output amplitude of each sub-channel caused by the optical loss caused by the effect reduces the offset of the beam pointing and the level of the grating lobe.

According to some embodiments of the present invention, the method further includes:

After scanning and detecting the target to obtain the position of the target, the optical switch controls to receive continuous laser light;

The intensity of the pulsed laser is modulated by an electro-optical intensity modulator and a communication signal is generated to send to the target.

The optical phased array device and the laser radar according to the present invention will be described in detail below with three specific embodiments. It is to be understood that the following description is merely illustrative and not specific to the limitation of the present invention.

The optical phased array device proposed by the present invention is a silicon-based optical phased array device integrating measurement and communication, which can be prepared on a silicon-on-insulator (SOI) wafer, and its preparation process is compatible with the CMOS process, which can effectively reduce the production cost and is easy to Integration with other microelectronic devices.

Example 1:

As shown in Figure 3, the optical phased array device includes: electro-optical intensity modulator, photodetector, optical switch, power division network, amplitude consistency network, phased array and grating array. The waveguide structure of the device can be a ridge waveguide structure or a strip waveguide structure.

The optical phased array device further includes an electrode part for driving the electro-optical modulator, phase shifter, optical switch and detection signal of the photodetector with an electrical signal.

As shown in FIG. 3 , the number of channels N=8 is taken as an example. Optical switches are used to connect continuous light lasers and pulsed light lasers outside the device. Among them, the continuous light source is used for subsequent calibration and communication, and the pulsed light source is used for subsequent measurement. The electro-optical intensity modulator is used for intensity modulation of continuous light to form an OOK (on-off key) modulation signal. The power division network is used to equally divide the light source into N sub-channels. The amplitude consistency network detects the optical power of each sub-channel through a photodetector, and then feedbacks and controls the adjustable attenuator to keep the output optical power of each sub-channel consistent. The electro-optical phase shifter of each sub-channel is used for phase modulation to form a phase difference and to control the direction of the emission beam. The grating array is used to couple light from the waveguide into free space to form a beam.

As shown in Figure 4, the structure of the optical switch is a 2×2 Mach-Zehnder Interferometer (MZI). The two transmission arms are of equal length, and one of the transmission arms is provided with an electro-optical phase shifter. The switching of the output ports is realized by adjusting the phase difference of the two transmission arms. The electro-optical phase shifter can adopt the electro-optical phase shifter with carrier dispersion effect , the carrier injection type PIN structure can be used, and the carrier depletion type PN structure can also be used. The waveguide cross sections of these two structures are shown in Figures 5 and 6.

The electro-optical intensity modulator is shown in Figure 8, and the structure is a Mach-Zehnder interferometer, wherein the 1×2 splitter and combiner can be a multimode interferometer structure or a directional coupler structure. The two arms of the MZI are of equal length, and electro-optic phase shifters are arranged on the two arms respectively, and a thermo-optic phase shifter is arranged on one arm. The structure of the electro-optical phase shifter is the same as that of the optical switch. The differential drive signal is loaded on the electro-optical phase shifter through the traveling wave electrode to form a push-pull drive mode. The end of the traveling wave electrode is configured with a matching impedance Zt (the impedance can be 33 ohms, 50 ohms and 100 ohms). The thermo-optic phase shifter uses the thermo-optic effect of the silicon waveguide to change the phase difference between the two arms, and adjusts the modulator to be at the half-wave operating point (-3dB). The continuous light is amplitude modulated by the modulator to form an OOK modulated signal.

A 1×N power division network can be implemented by cascading 1×2 power dividers. The 1×2 power divider can be implemented with a multimode interference structure or a directional coupler structure. Due to the process error, the actual splitting ratio of the 1×2 power splitter is not uniform. After multiple devices are cascaded, this non-uniformity is amplified, resulting in inconsistent optical power output from each channel, resulting in beam pointing offset and side lobes. Level up. In order to solve this problem, the present invention proposes an amplitude consistency network for adjusting the output optical power of each channel.

The amplitude adjustment function of each channel in the N-channel amplitude consistency network is completed by the adjustable attenuator, the directional coupler and the photodetector. Its working principle is: the ratio of the optical power output from the directional coupler to the grating and the output to the photodetector is m. The optical power of the channel output to the grating. According to the comparison between the output optical powers of each channel, the adjustable attenuator is adjusted so that the amplitudes between the channels tend to be consistent.

Each channel of the phase control array is equipped with a high-speed electro-optical phase shifter for high-speed phase adjustment (0 to 2π). The antenna array consists of a grating array structure.

The workflow of the measurement and communication integrated optical phased array silicon-based device:

S100, the device is powered on and started, and the optical switch is controlled to turn on the continuous wave laser, and the electro-optical intensity modulator does not work at this time.

S200, the device amplitude correction function is activated, the laser outputs a continuous wave, and the photodetector is activated to obtain the detection power (E1, E2, E3...En) of each channel photodetector.

S300, compare the optical power detected by all the photodetectors, and obtain the minimum optical power as the reference optical power Ex.

S400, adjust the adjustable attenuator in the amplitude correction network, so that the optical power output to the photodetector is equal to the reference optical power, and at this time, the amplitudes of each channel are consistent.

S500, start the measurement function of the device, control the optical switch to connect the pulsed laser, obtain the position of the target through the TOF technology, and estimate the movement speed and direction of the target by the distance differential method. Control the phased array to quickly scan the beam to form the target point cloud image.

S600, control the beam to point to the target, start the communication function, control the optical switch to turn on the continuous light laser again, start the electro-optical intensity modulator, and perform amplitude modulation on the optical signal.

Therefore, the present invention concentrates the functions of measurement and communication on one device, and realizes the unification of the two functions of measurement and communication through time division multiplexing.

Embodiment 2:

As shown in Figure 7, the difference from the first embodiment is that in this embodiment, the optical switch utilizes the silicon-based microring resonant cavity structure to realize the optical switch function. When the resonant wavelength is aligned with the wavelength of the light source, the input light of Port1 passes through The micro-ring enters port 3. When the resonant wavelength is far from the source wavelength of light, the input light of Port 1 is output to Port 3 through a straight waveguide. The resonant wavelength can be changed by adjusting the phase with a thermo-optic phase shifter.

FIG. 9 is a schematic structural diagram of an electro-optical intensity modulator according to a second example of the present invention. The electro-optical intensity modulator takes the form of a single-port push-pull drive. The DC bias is loaded on the DC electrode between the two arms, and the RF driving signal is loaded on the traveling wave electrode, and the matching impedance of the traveling wave electrode is 50 ohms. The phase shifter adopts a PN junction structure, Bias1 provides reverse bias for the PN junction, and Bias2 provides a static operating point for the modulator, so that the modulator works at the -3dB operating point. In this example, other structures and the obtained effects are basically the same as those in the first embodiment.

Embodiment three:

Different from the first embodiment, as shown in FIG. 10 , in this embodiment, the power division network includes a bus-type waveguide and N−1 directional couplers. The directional coupler is a waveguide placed in parallel with the bus waveguide. The ratio of the optical power output from the directional coupler to each channel to the bus optical power is 1/N, 1/(N-1) from the start to the end, respectively. 1/N, ..., 1/2, ensure that the optical power of each channel is 1/N of the input optical power. The other structures and the obtained effects are basically the same as those of the first embodiment.

To sum up, in order to integrate the measurement and communication functions of silicon photonic phased array devices, the present invention solves the problem of single function of existing silicon-based phased arrays. The invention designs a silicon-based phased array device integrating communication and measurement.

The invention connects the external continuous light laser and the pulse light laser through the optical switch, the amplitude correction and communication are connected with the continuous light laser, and the detection is connected with the pulse light laser. Electro-optical intensity modulator for amplitude modulation.

The present invention sets up an amplitude consistency network, including: the amplitude consistency network includes a directional coupler, a photodetector and an adjustable attenuator. The adjustable attenuator can be adjusted according to the detected optical power, and the output optical power of each channel can be controlled to achieve the consistency of the amplitude, thereby avoiding the beam pointing deviation and the sidelobe level being raised.

The present invention is a silicon photonics integrated device fabricated on a silicon-based SOI wafer. In the present invention, the optical power divider can also be fabricated using a silicon nitride waveguide, and the phase shifter can be fabricated using a thermal-optical phase shifter based on a silicon nitride waveguide. .

In addition, the optical switch of the present invention can be replaced by a wavelength division multiplexer. At this time, the wavelengths of the continuous light laser and the pulsed light laser are different, and the wavelength division multiplexer is used to synthesize one channel to access the modulator. The pulse laser works during detection, and the continuous light laser works during communication.

Through the description of the specific embodiments, it should be possible to have a more in-depth and specific understanding of the technical means and effects adopted by the present invention to achieve the predetermined purpose. However, the accompanying drawings are only for reference and description, not for the present invention. limit.

Claims (9)

1. An optical phased array device, characterized in that, the optical phased array device adopts a silicon-based optical phased array device, the silicon-based optical phased array device is prepared by a silicon wafer on an insulator, the optical phased array device includes:

the optical switch is used for controlling optical signals of different modes;

the electro-optical intensity modulator is connected with the optical switch and is used for modulating the intensity of the optical signal;

the power division network is connected with the electro-optical intensity modulator and used for distributing the optical signals to a plurality of sub-channels;

the amplitude consistency network is connected with the power distribution network and is used for detecting and adjusting the optical power of the optical signal in each subchannel;

the light-operated phased array comprises a plurality of electro-optical phase shifters, and each sub-channel is provided with the electro-optical phase shifter and used for adjusting the phase of the optical signal in the sub-channel;

the amplitude consistency network comprises:

a photodetector for detecting the optical power of the optical signal in each of the subchannels;

a directional coupler for adjusting the duty ratio of the optical signal input to the photodetector in each of the subchannels;

and the adjustable attenuator is used for adjusting the optical power of the optical signal in each sub-channel according to the optical power of the optical signal in each sub-channel, so that the optical power in each sub-channel is consistent.

2. The optical phased array device according to claim 1, wherein the optical switch is a mach-zehnder interferometer, and comprises two transmission arms and a first phase shifter disposed on at least one of the transmission arms, and the first phase shifter is configured to adjust a phase difference of the optical signals in the two transmission arms to control receiving of the optical signals of different modes.

3. The optical phased array device according to claim 2, wherein the first phase shifter is a PIN structure of a carrier injection type or a PN structure of a carrier depletion type.

4. The optical phased array device according to claim 2, wherein said first phase shifter is an electro-optical first phase shifter, and said electro-optical first phase shifter controls a phase difference of said optical signals in two of said transmission arms by using a carrier dispersion effect of a waveguide.

5. The optical phased array device according to claim 1, characterized in that the optical switch is adapted to control the reception of continuous laser light or pulsed laser light.

6. The optical phased array device according to any of claims 1 to 5, wherein the optical phased array device is a silicon-based optical phased array device fabricated using a silicon-on-insulator wafer.

7. A lidar characterized by comprising: the optical phased array device of any one of claims 1 to 6.

8. A lidar-based detection method, wherein the detection method employs the lidar of claim 7, and wherein the method comprises:

controlling to receive continuous laser through the optical switch;

detecting the optical power of an optical signal in each sub-channel through the amplitude consistency network, and adjusting the optical power of the optical signal in each sub-channel based on the optical power of the optical signal in each sub-channel so as to make the optical power in each sub-channel consistent;

starting a detection function of the laser radar, and receiving pulse laser through the optical switch light control;

and adjusting the phase of the received pulse laser in each sub-channel through the optical phased array, and outputting to form a scanning beam so as to scan and detect a target.

9. The lidar-based detection method of claim 8, wherein the method further comprises:

after the target is scanned and detected to obtain the position of the target, the optical switch controls to receive continuous laser;

and modulating the intensity of the continuous laser by the electro-optical intensity modulator and generating a communication signal to be sent to the target.

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