Phase control component control method based on partition time sequence rotation control, liquid crystal optical phased array beam tracking system and method

Abstract

The present application relates to light beam tracking device and method, specifically relates to phase control component control method based on partition time sequence rotation control, liquid crystal optical phased array light beam tracking system and method. In order to solve the prior art exists liquid crystal optical phased array low response frequency causes residual tracking error, reduces the light intensity stability, and the dynamic distortion caused by the process of liquid crystal molecule reorientation leads to the spot center drift, power drop or even instantaneous lockout, the deficiency, the present application is based on the phase control component control method of partition time sequence rotation control, the phase control component is set to N region, N >= 2;The deflection angle of light beam or the phase to be compensated is calculated, which is converted into the phase distribution of each region of the phase control component, the number of rotation is calculated, the region to be activated is calculated, the phase is updated, and the rotation control is carried out on each region in turn until the spot centroid position or wavefront phase meets the design requirements.

Description

Technical Field

[0001] This invention relates to beam tracking devices and methods, specifically to a phase modulation component control method based on partitioned timing rotation control, and a liquid crystal optical phased array beam tracking system and method. Background Technology

[0002] Space laser communication boasts advantages such as wide bandwidth, large information capacity, high security, strong anti-interference capability, no spectrum limitations, small size, light weight, and low power consumption, meeting the ever-increasing data demands of exploration missions and space-based communication networks. In recent years, multiple countries have successfully conducted on-orbit demonstrations and verifications of inter-satellite and satellite-to-ground space laser communication technology. Space laser communication technology has been widely applied in low-Earth orbit satellite constellations both domestically and internationally.

[0003] In space laser communication systems, the aiming, acquisition, and tracking subsystem is a crucial component. Through two stages of coarse and fine tracking, it achieves rapid acquisition of space light and ensures the beam enters the communication receiver stably and efficiently in real time, enabling high-speed data transmission. Existing space laser communication systems mostly employ rotating mechanical turntables. Coarse tracking and acquisition of the beam are achieved through the mechanical rotation of the turntable. However, these mechanical turntables have large size, weight, and power consumption of their optical antennas, accounting for over 70% of the space laser terminal's size, weight, and power resources. Furthermore, they suffer from high inertia and difficulty in expanding to multi-user simultaneous communication, limiting the development of space laser communication terminals towards miniaturization, lightweight design, and flexible networking.

[0004] Liquid crystal optical phased arrays (LCDs) achieve non-mechanical beam deflection through phase modulation, offering advantages such as small size, light weight, and low power consumption. Furthermore, programmable control through partitioning makes them a promising alternative to mechanical turntables in space laser communication. However, LCDs rely on the rearrangement of liquid crystal molecules for phase modulation, which is limited by the relaxation and rise time of the liquid crystal material. Therefore, their response frequency is typically only in the tens of hertz range, a limitation that significantly impacts aiming, acquisition, and tracking applications in space laser communication. Due to the limited bandwidth of LCDs, their output phase or wavefront correction commands cannot effectively respond to high-frequency disturbances such as attitude perturbations of space platforms and relative motion between platforms, resulting in residual tracking errors. Moreover, the low response frequency affects the light intensity stability during high-speed angle switching. Additionally, the liquid crystal molecules require a significant reorientation process, leading to dynamic distortion of the light field phase during switching, causing spot center drift, power reduction, and even momentary loss of lock. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies, such as residual tracking errors caused by the low response frequency of liquid crystal optical phased arrays, reduced light intensity stability, and dynamic distortion caused by the reorientation process of liquid crystal molecules leading to spot center drift, power reduction, or even instantaneous loss of lock. The invention provides a phase modulation component control method based on partitioned timing rotation control, a liquid crystal optical phased array beam tracking system and method.

[0006] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0007] A control method for a phase modulation component based on partitioned timing rotation control, characterized by the following steps:

[0008] S1, Set the initial phase distribution of the phase control component, wherein the phase control component is set to N regions, and the incident light falls uniformly on the N regions, where N≥2;

[0009] S2, based on the captured image of the current beam spot, detect the position of the beam spot centroid and obtain the information on the miss distance of the beam spot centroid, or based on the wavefront information of the beam detected by the wavefront sensor, obtain the wavefront phase distribution of the beam.

[0010] S3. Based on the spot centroid miss distance information or wavefront phase distribution obtained in step S2, calculate the beam deflection angle or the phase to be compensated, and convert it into the phase distribution of each region of the corresponding phase control component.

[0011] S4. Calculate the region to be activated based on the value of the rotation number k. The initial value of the rotation number k is set to 1. Calculate k / N and take the remainder. The remainders are 1, 2, ..., N-1, 0, which correspond to N regions in turn.

[0012] S5, the phase distribution of the region to be activated obtained in step S3 is loaded into the corresponding region of the phase control component, so that the region is updated in phase, thereby realizing the deflection or wavefront correction of the target beam, while other regions maintain the previous phase state.

[0013] S6, set the number of rotations k to k+1, return to step S2, and enter the next rotation control until the position of the spot centroid or the wavefront phase meets the design requirements.

[0014] Furthermore, in step S4, the cycle period of the N region rotation control is the response time t0 of the phase control component;

[0015] The signal activation times for the N regions are 0, t0 / N, 2t0 / N, ..., (N-1)t0 / N.

[0016] This invention also provides a liquid crystal optical phased array beam tracking system based on partitioned time-sequential control, characterized in that it includes a liquid crystal optical phased array, a beam expander / contractor unit, and a fast reflector arranged sequentially along the optical axis; a beam splitter unit disposed on the reflection path of the fast reflector; and a tracking unit, a transmitting unit, and a receiving unit disposed corresponding to the beam splitter unit. The liquid crystal optical phased array is used to receive incident light signals and emit outgoing light signals. The liquid crystal optical phased array is uniformly divided into N regions, where N≥2, and each region responds independently to the phase distribution control signal. The beam expander / contractor unit is used to adjust the aperture and divergence angle of the incident light signal and the outgoing light signal to match the fast reflector and the liquid crystal optical phased array, respectively. The fast reflector is used to reflect the beam after beam expansion / contraction. The incident light signal of the unit is reflected to the beam splitting unit, and the outgoing light signal is reflected to the beam expander / contractor unit; the incident light signal includes tracking light or a first signal light emitted by an external system; the beam splitting unit is used to transmit the tracking light reflected by the fast reflector to the tracking unit, and the first signal light to the receiving unit for photoelectric conversion and demodulation; the tracking unit is connected to the liquid crystal optical phased array and is used to image the tracking light, obtain the corresponding spot position information and analyze it, and control the N regions of the liquid crystal optical phased array respectively according to the analysis result and the applied voltage; the transmitting unit is used for signal modulation and loading, generating a second signal light as the outgoing light signal, which is transmitted through the beam splitting unit and then sequentially transmitted through the fast reflector, the beam expander / contractor unit, and the liquid crystal optical phased array.

[0017] Furthermore, the beam splitting unit includes a first beam splitting prism and a second beam splitting prism disposed on the reflected light path of the first beam splitting prism, for energy beam splitting;

[0018] The tracking unit is disposed on the transmission light path of the first beam splitter;

[0019] The transmitting unit is disposed on the reflected light path of the second beam splitter;

[0020] The receiving unit is disposed on the transmission light path of the second beam splitter.

[0021] Furthermore, the tracking unit includes a tracking focusing module, a tracking camera, and a control module arranged sequentially along the optical path; the tracking focusing module is used to focus the incident light signal onto the tracking camera, the tracking camera images it, and the control module is used to analyze the position information of the imaged light spot and control the N regions of the liquid crystal optical phased array respectively according to the analysis result by applying voltage;

[0022] The transmitting unit includes a communication transmitting module and a beam expander module disposed at the output end of the communication transmitting module; the communication transmitting module is used for signal modulation and loading, and the beam expander module is used for beam expanding and transmitting the second signal light of the communication transmitting module to the beam splitter unit;

[0023] The receiving unit includes a receiving coupling module and a communication receiving module arranged sequentially along the optical path. The receiving coupling module is used to couple the first signal light to the communication receiving module, and the communication receiving module is used to perform photoelectric conversion and demodulation.

[0024] Furthermore, the angle between the fast reflector and the optical axis is 45°.

[0025] Meanwhile, this invention also provides a liquid crystal optical phased array beam tracking method based on partitioned timing rotation control, which is characterized by including the following steps:

[0026] Step 1: Construct the above-mentioned liquid crystal optical phased array beam tracking system based on partitioned timing rotation control. According to communication requirements, the liquid crystal optical phased array is evenly divided into N regions.

[0027] Step 2: Based on the response time of the liquid crystal optical phased array, set different timing for loading phase distribution control signals for each of the N regions;

[0028] Step 3: The liquid crystal optical phased array is used as a phase modulation component, and the tracking light is used as the incident light. The light spot image of the incident light is captured by the tracking unit. The phase modulation component control method based on partitioned time-sequence rotation control is used to sequentially modulate the phase of the N regions of the liquid crystal optical phased array to achieve beam deflection until the design requirements are met.

[0029] Compared with the prior art, the present invention has the following beneficial technical effects:

[0030] 1. The phase control component control method based on partitioned timing rotation control of the present invention utilizes the programmable control characteristics of the phase control component to divide the phase control component into N regions, and each region is controlled in turn according to the sequence. This overcomes the limitation of low response frequency of the phase control component and improves the equivalent control bandwidth and communication stability under the condition that its indicators remain unchanged.

[0031] 2. In the phase control component control method based on partitioned time-sequential switching control of the present invention, the cycle period of the N regions switching control is the response time t0 of the phase control component. Under the condition that the response time of the phase control component remains unchanged, the equivalent control bandwidth of the liquid crystal optical phased array is increased by N times.

[0032] 3. The liquid crystal optical phased array beam tracking system based on partitioned timing rotation control of the present invention is based on the above method, which divides the liquid crystal optical phased array into N regions, so that each region responds to the phase distribution control signal independently. Under the condition that the performance of the liquid crystal optical phased array itself remains unchanged, its response frequency and control bandwidth are effectively improved, thereby improving the tracking accuracy.

[0033] 4. The liquid crystal optical phased array beam tracking method based on partitioned timing rotation control of the present invention can reduce the proportion of the liquid crystal optical phased array in the angle switching process, and greatly reduce the fluctuation of coupled light power caused by the angle switching of the liquid crystal optical phased array during the tracking process. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of an embodiment of the liquid crystal optical phased array beam tracking system based on partitioned time-sequence rotation control of the present invention (control module not shown).

[0035] Figure 2 This is a schematic diagram of the region setting of the liquid crystal optical phased array in an embodiment of the liquid crystal optical phased array beam tracking system based on partitioned time-sequence rotation control of the present invention;

[0036] Figure 3 This is a flowchart of an embodiment of the phase modulation component control method based on partitioned timing rotation control of the present invention.

[0037] The annotations in the attached figures are explained as follows:

[0038] 1-Liquid crystal optical phased array, 2-Beam expander and shrinker unit, 3-Fast reflector, 4-First beam splitter prism, 5-Tracking and focusing module, 6-Tracking camera, 7-Second beam splitter prism, 8-Transmit beam expander module, 9-Communication transmitter module, 10-Receiver coupling module, 11-Communication receiver module. Detailed Implementation

[0039] like Figure 1 As shown, the liquid crystal optical phased array beam tracking system based on partitioned time-sequence rotation control of the present invention includes a liquid crystal optical phased array 1, a beam expander / contractor unit 2, a fast reflector 3, a first beam splitter prism 4, a tracking and focusing module 5, a tracking camera 6, a second beam splitter prism 7, a transmitting beam expander module 8, a communication transmitting module 9, a receiving coupling module 10, and a communication receiving module 11.

[0040] The liquid crystal optical phased array 1, the beam expander / contractor unit 2, and the fast reflector 3 are arranged sequentially along the optical axis and located on the same central axis. The beam expander / contractor unit 2 is used to adjust the aperture and divergence angle of the incident light signal and the emitted light signal to match the fast reflector 3 and the liquid crystal optical phased array 1, respectively. The fast reflector 3 is placed at 45° with the central axis. The incident light signal includes tracking light and the first signal light emitted by the external system.

[0041] Both the first beam splitter 4 and the second beam splitter 7 split the incident light into two paths through energy beam splitting. The first beam splitter 4, the tracking and focusing module 5, and the tracking camera 6 are sequentially arranged on the reflected light path of the fast reflector 3 and located on the same central axis. The tracking and focusing module 5 and the tracking camera 6 serve as tracking units, and the first beam splitter 4 transmits the tracking light to the tracking unit to achieve target tracking. The second beam splitter 7 is arranged on the reflected light path of the first beam splitter 4 and transmits the light split from the main light path of the first beam splitter 4, namely the first signal light. The receiving coupling module 10 and the communication receiving module 11 serve as receiving units and are sequentially arranged on the transmitted light path of the second beam splitter 7. The receiving coupling module 10 is used to couple the first signal light to the communication receiving module 11, and the communication receiving module 11 is used for photoelectric conversion and demodulation. The beam expansion module 8 and the communication transmission module 9 are sequentially arranged as transmission units on the reflected light path of the second beam splitter 7. The communication transmission module 9 is used for signal modulation and loading, and emits a second signal light as the outgoing light signal. The beam expansion module 8 is used to expand the second signal light emitted by the communication transmission module 9 and transmit it into free space to the second beam splitter 7.

[0042] The liquid crystal optical phased array 1 is used to receive incident light signals and emit outgoing light signals. Beam deflection and transmission are achieved by controlling the deflection angle of the liquid crystal pixels. Based on the requirements of space laser communication, the liquid crystal optical phased array 1 is uniformly divided into N regions, where N≥2. The incident light from the liquid crystal optical phased array 1 falls uniformly on the N regions, with equal light intensity in each region. Each region responds independently to the phase distribution control signal, and each region has a different phase distribution control signal and a different loading timing. The phase distribution control signal corresponds to the loading voltage sequence of the phase distribution. The loading timing includes the signal start time, duration, and loading period, allowing different regions to receive their respective control signals at different time periods, forming a timing window for each region. The N regions are controlled sequentially according to the signal start time. (Reference) Figure 2 In this embodiment, N=4, and the four regions are labeled A, B, C, and D respectively.

[0043] In this embodiment, a transmissive liquid crystal optical phased array is used as the phase control component. In other embodiments of the present invention, other different types of liquid crystal optical phased arrays 1, spatial light modulators, and other programmable partition control phase control components can also be used, all of which can achieve corresponding improvements in control performance.

[0044] The tracking unit also includes a control module, which is connected to the liquid crystal optical phased array 1. The control module is used to analyze the position information of the imaging spot, convert it into the target deflection angle, and apply voltage to control the N regions of the liquid crystal optical phased array 1 respectively.

[0045] The present invention provides a phase control method for a phase modulation component based on partitioned timing rotation control, which is used to control the phase modulation component to achieve high control bandwidth and high precision phase adjustment. In this embodiment, the phase modulation component adopts a liquid crystal optical phased array 1 to realize the fast continuous beam tracking function in the liquid crystal optical phased array beam tracking system.

[0046] The principle of the partitioned timing rotation control is as follows: based on the response time t0 of the phase modulation component, different loading times for control signals are set for N regions. In this embodiment, cyclic control is performed in the order of A, B, C, D, A... to achieve sequential control of the N regions. The rotation number k is defined, and k increments from 1. Starting from k=1 (the first rotation control), i.e., at time t=0, a control signal is loaded for region A; at k=2 (time t=t0 / 4), a control signal is loaded for region B; at k=3 (time t=t0 / 2), a control signal is loaded for region C; and at k=4 (time t=3t0 / 4), a control signal is loaded for region D. The duration and loading period of the control signal are both t0. When the control signal is loaded, only the corresponding region within the corresponding timing window is activated, and the phase distribution control signal is transmitted to the corresponding region of the liquid crystal optical phased array 1, causing the liquid crystal pixels in that region to update their phase according to the preset phase distribution, thereby achieving target wavefront modulation or beam deflection. The remaining regions without loaded control signals maintain their original state. After each rotation control is completed, the next rotation control begins based on the new spot information. Through periodic regional rotation control, continuous, stable and dynamically adjustable phase distribution control is achieved.

[0047] refer to Figure 2 In this embodiment, the workflow of the phase modulation component control method based on partitioned timing rotation control is as follows:

[0048] (1) System initialization: calculate and set the initial phase distribution for the four regions respectively, and set the initial value of the rotation number k to 1.

[0049] (2) At the start of the kth cycle, the spot image of the current beam is captured by the tracking camera 6, the position of the spot centroid is detected, and the off-target information of the spot centroid is obtained.

[0050] (3) Based on the spot centroid off-target information obtained in step (2), calculate the beam deflection angle and convert it into the phase distribution of each region of the corresponding liquid crystal optical phased array 1.

[0051] (4) Calculate the region to be activated based on the value of k. Specifically, calculate k / N and take the remainder. If the remainder is 1, activate region A; if the remainder is 2, activate region B; if the remainder is 3, activate region C; if the remainder is 0, activate region D.

[0052] (5) The phase distribution of the corresponding currently activated region obtained in step (3) is loaded into the corresponding region of the liquid crystal optical phased array 1, so that the liquid crystal pixels in the region are updated according to the phase distribution in step (3), thereby achieving the deflection of the target beam and keeping the other three regions in the previous phase state.

[0053] (6) Set the number of rotations k to k+1, return to step (2), and enter the next rotation control until the design requirements are met.

[0054] In other embodiments of the present invention, the above method can also be applied to wavefront phase modulation. In step (2), the wavefront information of the beam is detected by the wavefront sensor to obtain the wavefront phase distribution of the beam. In step (3), the phase to be compensated is calculated and converted into the phase distribution of each region of the corresponding phase control component. Then, the phase is updated through the above steps (4) and (5) to realize high-speed and high-frequency control of the phase control component, perform target wavefront phase modulation, and realize wavefront correction.

[0055] When using the above method for beam tracking in a liquid crystal optical phased array beam tracking system, the following steps are included:

[0056] Step 1: According to the requirements of space laser communication, the liquid crystal optical phased array 1 is evenly divided into N regions;

[0057] Step 2: Based on the response time of the liquid crystal optical phased array 1, set different timing for loading phase distribution control signals for each of the N regions;

[0058] Step 3: The tracking light is incident on the liquid crystal optical phased array 1. The spot image of the incident light is captured by the tracking unit. According to the above steps (1) to (6), the N regions of the liquid crystal optical phased array 1 are sequentially phase modulated to achieve beam deflection, so that the liquid crystal optical phased array 1 can achieve continuous and stable beam tracking until the center of the spot is located at the center of the image plane, which meets the design requirements.

[0059] This embodiment demonstrates that, compared to traditional methods, the liquid crystal optical phased array beam tracking method based on partitioned time-sequential control of the present invention can achieve high-bandwidth control with a control period of t0 / N, while maintaining the same response time t0 for the phase modulation component. This increases the equivalent control bandwidth of the liquid crystal optical phased array 1 by N times. Simultaneously, the time-sequential control reduces phase dynamic distortion fluctuations caused by phase distribution switching, improving tracking accuracy and communication stability. This invention solves the problems of low control bandwidth, beam center drift, and power reduction in existing tracking methods, expanding the application of the liquid crystal optical phased array 1 in the field of space laser communication.

Claims

1. A control method for a phase modulation component based on partitioned timing switching control, characterized in that, Includes the following steps: S1, Set the initial phase distribution of the phase control component, wherein the phase control component is set to N regions, and the incident light falls uniformly on the N regions, where N≥2; S2, based on the captured image of the current beam spot, detect the position of the beam spot centroid and obtain the information on the miss distance of the beam spot centroid, or based on the wavefront information of the beam detected by the wavefront sensor, obtain the wavefront phase distribution of the beam. S3. Based on the spot centroid miss distance information or wavefront phase distribution obtained in step S2, calculate the beam deflection angle or the phase to be compensated, and convert it into the phase distribution of each region of the corresponding phase control component. S4. Calculate the region to be activated based on the value of the rotation number k. The initial value of the rotation number k is set to 1. Calculate k / N and take the remainder. The remainders are 1, 2, ..., N-1, 0, which correspond to N regions in turn. S5, the phase distribution of the region to be activated obtained in step S3 is loaded into the corresponding region of the phase control component, so that the region is updated in phase, thereby realizing the deflection or wavefront correction of the target beam, while other regions maintain the previous phase state. S6, set the number of rotations k to k+1, return to step S2, and enter the next rotation control until the position of the spot centroid or the wavefront phase meets the design requirements.

2. The phase modulation component control method based on partitioned timing rotation control according to claim 1, characterized in that: In step S4, the cycle period of the N region rotation control is the response time t0 of the phase control component; The signal activation times for the N regions are 0, t0 / N, 2t0 / N, ..., (N-1)t0 / N.

3. A liquid crystal optical phased array beam tracking system based on partitioned time-sequenced control, characterized in that: It includes a liquid crystal optical phased array (1), a beam expander and shrinker unit (2), and a fast reflector (3) arranged sequentially along the optical axis, a beam splitter unit arranged on the reflected light path of the fast reflector (3), and a tracking unit, a transmitting unit, and a receiving unit arranged in the corresponding beam splitter unit; The liquid crystal optical phased array (1) is used to receive incident light signals and emit outgoing light signals. The liquid crystal optical phased array (1) is uniformly divided into N regions, where N≥2, and each region responds to the phase distribution control signal independently. The beam expanding and shrinking unit (2) is used to adjust the aperture and divergence angle of the incident light signal and the outgoing light signal to match the fast reflector (3) and the liquid crystal optical phased array (1) respectively. The fast reflector (3) is used to reflect the incident light signal after passing through the beam expander and beam shrinker unit (2) to the beam splitter unit and to reflect the outgoing light signal to the beam expander and beam shrinker unit (2). The incident light signal includes tracking light or a first signal light emitted by an external system; The beam splitting unit is used to transmit the tracking light reflected by the fast reflector (3) to the tracking unit and the first signal light to the receiving unit for photoelectric conversion and demodulation. The tracking unit is connected to the liquid crystal optical phased array (1) and is used to image the tracking light, obtain the corresponding spot position information and analyze it. Based on the analysis results, the voltage is applied to control the N regions of the liquid crystal optical phased array (1) respectively. The transmitting unit is used for signal modulation and loading, generating a second signal light as the emitted light signal, which is transmitted through the beam splitting unit and then emitted sequentially through the fast reflector (3), the beam expander and shrinker unit (2), and the liquid crystal optical phased array (1).

4. The liquid crystal optical phased array beam tracking system based on partitioned timing rotation control according to claim 3, characterized in that: The beam splitting unit includes a first beam splitting prism (4) and a second beam splitting prism (7) disposed on the reflected light path of the first beam splitting prism (4) for energy beam splitting; The tracking unit is disposed on the transmission light path of the first beam splitter (4); The transmitting unit is disposed on the reflected light path of the second beam splitter (7); The receiving unit is disposed on the transmission light path of the second beam splitter (7).

5. The liquid crystal optical phased array beam tracking system based on partitioned timing rotation control according to claim 3, characterized in that: The tracking unit includes a tracking focusing module (5), a tracking camera (6), and a control module arranged sequentially along the optical path; the tracking focusing module (5) is used to focus the incident light signal onto the tracking camera (6), the tracking camera (6) images it, and the control module is used to analyze the position information of the imaged light spot and control the N regions of the liquid crystal optical phased array (1) according to the analysis results. The transmitting unit includes a communication transmitting module (9) and a transmitting beam expander module (8) disposed at the output end of the communication transmitting module (9); the communication transmitting module (9) is used for signal modulation and loading, and the transmitting beam expander module (8) is used to transmit the second signal light of the communication transmitting module (9) to the beam splitter unit. The receiving unit includes a receiving coupling module (10) and a communication receiving module (11) arranged sequentially along the optical path. The receiving coupling module (10) is used to couple the first signal light to the communication receiving module (11), and the communication receiving module (11) is used to perform photoelectric conversion and demodulation.

6. The liquid crystal optical phased array beam tracking system based on partitioned timing rotation control according to any one of claims 3-5, characterized in that: The angle between the fast reflector (3) and the optical axis is 45°.

7. A method for tracking a liquid crystal optical phased array beam based on partitioned time-sequenced control, characterized in that, Includes the following steps: Step 1: Construct the liquid crystal optical phased array beam tracking system based on partitioned time-sequence rotation control as described in claim 3. According to communication requirements, the liquid crystal optical phased array (1) is uniformly divided into N regions. Step 2: Based on the response time of the liquid crystal optical phased array (1), set different phase distribution control signal loading times for each of the N regions; Step 3: The liquid crystal optical phased array (1) is used as a phase modulation component. The tracking light is used as the incident light and is incident on the liquid crystal optical phased array (1). The spot image of the incident light is captured by the tracking unit. The phase modulation component control method based on partitioned time-sequence rotation control described in claim 1 is used to sequentially modulate the N regions of the liquid crystal optical phased array (1) to achieve beam deflection until the design requirements are met.

Images