Control method, control module and related apparatus of LCPG unit

Abstract

This application provides a control method, control module, and related apparatus for an LCPG unit. The method includes: when driving a liquid crystal waveplate based on a first voltage value, adjusting the first voltage value to a second voltage value, where the second voltage value is lower than the first voltage value. After maintaining the second voltage value for a first duration, adjusting to a third voltage value to drive the liquid crystal waveplate; wherein the third voltage value is lower than the first voltage value but higher than the second voltage value. Thus, in adjusting the driving voltage value of the liquid crystal waveplate from the first voltage value to the third voltage value, the first voltage value is first adjusted to a second voltage value, which is lower than the third voltage value, and then the voltage is increased from the second voltage value to the third voltage value, thereby shortening the time required for the liquid crystal waveplate to convert the phase delay of the light beam.

Description

[0001] This application claims priority to Chinese Patent Application No. 202610214896.6, filed on February 13, 2026, entitled "Control Method, Control Module and Related Device for LCPG Unit", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of liquid crystal technology, and in particular to a control method, control module and related device for an LCPG unit. Background Technology

[0003] A liquid crystal waveplate is an optical element fabricated based on the anisotropic optical properties of liquid crystal molecules, used to achieve phase delay of a light beam.

[0004] For example, liquid crystal waveplates can modulate the phase between different polarization components of an incident light beam, achieving the conversion of the light polarization state. Typically, the phase retardation is related to the driving voltage applied to the liquid crystal waveplate. Within the range between the threshold voltage and the saturation voltage, the phase retardation changes monotonically with the driving voltage.

[0005] Currently, when the driving voltage applied to the liquid crystal waveplate switches from high voltage to low voltage, the time required for the liquid crystal waveplate to convert the phase delay of the beam is usually long, which affects the efficiency of using the liquid crystal waveplate to switch the beam state. Summary of the Invention

[0006] This application provides a control method, control module, and related apparatus for an LCPG unit, which can shorten the time required for the phase delay of the light beam to be converted by the liquid crystal waveplate when the driving voltage applied to the liquid crystal waveplate is switched from high voltage to low voltage, thereby improving the efficiency of switching the light beam state using the liquid crystal waveplate.

[0007] In a first aspect, embodiments of this application provide a control method for an LCPG cell, applied to an LCPG cell, the LCPG cell including a liquid crystal waveplate; the method includes:

[0008] When driving the liquid crystal waveplate based on a first voltage value, the first voltage value is adjusted to a second voltage value, where the second voltage value is less than the first voltage value;

[0009] After maintaining the second voltage value for a first duration, the liquid crystal waveplate is driven by adjusting to a third voltage value; wherein the third voltage value is less than the first voltage value but greater than the second voltage value.

[0010] In one possible implementation, the second voltage value falls within the range of 0V to KmV, where K is a value greater than or equal to 1.

[0011] In one possible implementation, K can take any of the following values: 10, 30, 50, 80, 100, 150, 300.

[0012] In one possible implementation, the second voltage value is equal to 0V.

[0013] In one possible implementation, the driving voltage value of the liquid crystal waveplate is the peak-to-peak voltage value of a square wave signal, which is the signal used to drive the liquid crystal waveplate.

[0014] In one possible implementation, when the liquid crystal waveplate is driven based on a first voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate points in a first direction, so that the liquid crystal waveplate is in a stable first working state.

[0015] When the liquid crystal waveplate is driven based on the third voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate points in the second direction, so that the liquid crystal waveplate is in a stable second working state.

[0016] In one possible implementation, the driving voltage value of the liquid crystal waveplate is directly adjusted from a first voltage value to a third voltage value, and the time required to maintain the third voltage value so that the long axis of the liquid crystal molecules in the liquid crystal waveplate changes from the first direction to the second direction is a second time, and the first time is less than the second time.

[0017] In one possible implementation, the method further includes:

[0018] When driving the liquid crystal waveplate based on the fourth voltage value, the voltage driving the liquid crystal waveplate is directly adjusted to the fifth voltage value, which is higher than the fourth voltage value.

[0019] In one possible implementation, the fourth voltage value is equal to the third voltage value, and the fifth voltage value is equal to the first voltage value.

[0020] In one possible implementation, when the liquid crystal waveplate is driven based on the fourth voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate is oriented in the third direction, so that the liquid crystal waveplate is in a stable third working state.

[0021] When the liquid crystal waveplate is driven based on the fifth voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate points to the fourth direction, so that the liquid crystal waveplate is in a stable fourth working state.

[0022] Specifically, the driving voltage value of the liquid crystal waveplate is directly adjusted from the fourth voltage value to the fifth voltage value, and the time required to maintain the fifth voltage value so that the long axis of the liquid crystal molecules in the liquid crystal waveplate changes from the third direction to the fourth direction is the fourth time; the driving voltage value of the liquid crystal waveplate is directly adjusted from the fifth voltage value to the fourth voltage value, and the time required to maintain the fourth voltage value so that the long axis of the liquid crystal molecules in the liquid crystal waveplate changes from the fourth direction to the third direction is the fifth time, and the fourth time is less than the fifth time.

[0023] In one possible implementation, the LCPG unit further includes an LCPG sheet for deflecting the incident light beam modulated by the liquid crystal waveplate.

[0024] The method also includes adjusting the driving voltage value of the liquid crystal waveplate according to the desired beam deflection angle.

[0025] Secondly, embodiments of this application provide a control module for an LCPG unit, including a memory and a processor. The memory is configured to store computer-executable instructions. The processor is configured to execute the computer-executable instructions stored in the memory, causing the processor to perform the methods described in the first aspect and various possible embodiments thereof.

[0026] Thirdly, embodiments of this application provide an LCPG unit, including: a liquid crystal wave plate, at least one LCPG plate, and a control module as described in the second aspect.

[0027] Fourthly, embodiments of this application provide an optical deflection device comprising a plurality of cascaded LCPG units as described in the third aspect.

[0028] Fifthly, embodiments of this application provide a lidar, including an LCPG unit as described in the third aspect or an optical deflection device as described in the fourth aspect.

[0029] In a sixth aspect, embodiments of this application provide an electronic device including a lidar as described in the fifth aspect.

[0030] In a seventh aspect, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the methods described in the first aspect and various possible implementations of the first aspect.

[0031] Eighthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the methods described in the first aspect and various possible implementations of the first aspect.

[0032] The control method, control module, and related apparatus for the LCPG unit provided in this application adjust the driving voltage value of the liquid crystal waveplate from a first voltage value to a third voltage value by first adjusting the first voltage value to a second voltage value that is lower than the third voltage value, and then boosting the voltage from the second voltage value to the third voltage value.

[0033] In this process, the voltage difference between the first and second voltage values ​​is greater than the voltage difference between the first and third voltage values. For the liquid crystal molecules in the liquid crystal waveplate, the orientation of the long axis of the liquid crystal molecules is deflected due to the pressure difference. The greater the pressure difference, the faster the long axis of the liquid crystal molecules deflects.

[0034] Therefore, adjusting the first voltage value to the second voltage value can accelerate the deflection of the long axis of the liquid crystal molecules towards a direction different from the current orientation. When the long axis of the liquid crystal molecules is close to the long axis orientation corresponding to the third voltage value, the driving voltage is adjusted back to the third voltage value, so that the liquid crystal molecules are stabilized in the long axis orientation corresponding to the third voltage value.

[0035] Therefore, it is possible to shorten the state switching time of the liquid crystal waveplate caused by switching the voltage driving the liquid crystal waveplate from the first voltage value (i.e., high voltage) to the third voltage value (i.e., low voltage). Attached Figure Description

[0036] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0037] Figure 1 This application provides a schematic diagram of the implementation of beam deflection in an embodiment. Figure 1 ;

[0038] Figure 2 This application provides a schematic diagram of the implementation of beam deflection in an embodiment. Figure 2 ;

[0039] Figure 3 A schematic diagram of an LCPG unit provided in an embodiment of this application;

[0040] Figure 4 Schematic diagram of the implementation of the square wave signal provided in the embodiments of this application Figure 1 ;

[0041] Figure 5 Schematic diagram of the implementation of the square wave signal provided in the embodiments of this application Figure 2 ;

[0042] Figure 6 This application provides an example of a state switching implementation. Figure 1 ;

[0043] Figure 7 Flowchart of the control method for the LCPG unit provided in the embodiments of this application Figure 1 ;

[0044] Figure 8 This application provides an example of a state switching implementation. Figure 2 ;

[0045] Figure 9 Flowchart of the control method for the LCPG unit provided in the embodiments of this application Figure 2 ;

[0046] Figure 10 This is a schematic diagram of the control module of the LCPG unit provided in the embodiments of this application;

[0047] Figure 11 This is a schematic diagram of the structure of the LCPG unit provided in the embodiments of this application;

[0048] Figure 12 This is a schematic diagram of the structure of the optical deflection device provided in the embodiments of this application;

[0049] Figure 13 This is a schematic diagram of the structure of a lidar provided in an embodiment of this application;

[0050] Figure 14 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application;

[0051] Figure 15 This is a schematic diagram of the structure of a computer-readable storage medium provided in an embodiment of this application;

[0052] Figure 16 This is a schematic diagram of the structure of a computer program product provided in an embodiment of this application.

[0053] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0054] To facilitate understanding of the embodiments of this application, the following points will be explained first:

[0055] First, in the embodiments of this application, the indication includes explicit indication (also known as direct indication) and implicit indication (also known as indirect indication). Explicit indication information A refers to including information A; implicit indication information A refers to indicating information A through the correspondence between information A and information B and direct indication information B. The correspondence between information A and information B can be predefined, pre-stored, pre-burned, or pre-configured; or it can refer to indicating information A through information B and preset rules.

[0056] Second, in the embodiments of this application, information C is used to determine information D, which includes determining information D based solely on information C, as well as determining it based on information C and other information. Furthermore, information C can also be used to determine information D indirectly, for example, in the case where information D is determined based on information E, and information E is determined based on information C.

[0057] Third, in the embodiments of this application, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates an "or" relationship between the preceding and following related objects, but it does not exclude the possibility of indicating an "and" relationship. The specific meaning can be understood in conjunction with the context. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c; a and b; a and c; b and c; or a and b and c. Here, a, b, and c can be single or multiple.

[0058] Fourth, in the embodiments of this application, the use of prefixes such as "first" and "second" is merely for the purpose of distinguishing and describing different things belonging to the same name category, and does not constrain the order, size, or quantity of things. For example, "first threshold" and "second threshold" are simply different thresholds, and there is no temporal order, size, or priority relationship between them.

[0059] Fifth, the "sending" and "receiving" in the embodiments of this application can be performed between devices, such as between a second device and a first device; or they can be performed within a device, such as between components, modules, chips, software modules, or hardware modules within a device via a bus, wiring, or interface.

[0060] Sixth, in the embodiments of this application, "when," "if," and "if" all refer to the device making corresponding processing under certain objective circumstances, and are not limited to a time, nor do they require the device to make a judgment action when it is implemented, nor do they mean that there are other limitations.

[0061] Seventh, in the embodiments of this application, the words "example," "exemplarily," "for example," or "such as" are used to indicate that they are examples, illustrations, or explanations. Any embodiment or design that is described as "example," "exemplarily," "for example," or "such as" in this application should not be construed as being more preferred or advantageous than other embodiments or design options. Specifically, the use of the words "example," "exemplarily," "for example," or "such as" is intended to present the relevant concepts in a specific manner.

[0062] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0063] To better understand the technical solution of this application, the technical terms involved in this application will be introduced below.

[0064] 1. Left-handed circularly polarized light and right-handed circularly polarized light

[0065] Left-handed and right-handed circularly polarized light represent two polarization states of light. Light emitted from ordinary light sources exhibits random electric field vibrations. Circularly polarized light, however, is a special type of polarized light; the tip of its electric field vector traces a spiral trajectory over time during propagation.

[0066] When facing the direction from which the light beam is coming, if the electric field rotates counterclockwise, this is left-handed circularly polarized light. When facing the direction from which the light beam is coming, if the electric field rotates clockwise, this is right-handed circularly polarized light.

[0067] 2. LCPG

[0068] A liquid crystal polarization grating (LCPG) is an optical element based on the structure of liquid crystal molecules. LCPGs modulate the polarization state and propagation direction of incident light through the optical anisotropy (i.e., birefringence) of periodically arranged liquid crystal molecules. Unlike active LCPGs, passive LCPGs typically have fixed optical properties after fabrication and do not require dynamic adjustment using external electric fields or driving signals.

[0069] 3. Diffraction beam

[0070] When light passes through a periodic structure (grating) like an LCPG, it does not simply travel in a straight line, but rather "splits" into multiple beams that exit at different angles. This physical phenomenon is called diffraction. These beams of light that are generated by diffraction and travel in different directions are called diffracted beams.

[0071] 4. Diffraction order

[0072] To distinguish diffracted beams from different directions, they can be numbered using orders.

[0073] Zero order (0th order): corresponds to a beam of light that passes through directly without changing direction.

[0074] Positive Level 1 (+1): A beam of light deflected at a specific angle to one side of the grating.

[0075] Negative first order (-1 order): A beam of light deflected at the same angle (but in a different direction than the positive first order) to the other side of the grating.

[0076] Theoretically, there are even higher levels (such as ±2 levels), which will not be elaborated here.

[0077] 5. Liquid crystal waveplate

[0078] A liquid crystal waveplate is an optical phase delay device based on the principle of liquid crystal optical anisotropy (birefringence) that allows for the manipulation of the polarization state of light. Its core function is to convert light from one polarization state to another by introducing a controllable phase delay.

[0079] Based on the above introduction, the relevant implementations involved in the embodiments of this application will be described below.

[0080] In one implementation, LCPG can achieve beam deflection. It can be combined with... Figure 1 and Figure 2 Understanding beam deflection. Figure 1 This application provides a schematic diagram of the implementation of beam deflection in an embodiment. Figure 1 , Figure 2 This application provides a schematic diagram of the implementation of beam deflection in an embodiment. Figure 2 .

[0081] LCPG can achieve beam deflection, where the deflection direction depends on the circular polarization direction of the incident light.

[0082] In one example, when the incident light of the LCPG is left-handed circularly polarized light, the diffracted beam consists only of a beam with a diffraction order of negative first order. For example... Figure 1As shown, the rotation direction of the electric field vector of the incident light 101 of the LCPG is the direction indicated by arrow a (counterclockwise when facing the direction from which the beam is emitted), which indicates that the incident light is left-handed circularly polarized light. After the incident light 101 passes through the LCPG, a diffracted beam 102 can be formed. The rotation direction of the electric field vector of the diffracted beam 102 can be the direction indicated by arrow b, which indicates that the diffracted beam is right-handed circularly polarized light.

[0083] By comparing the beam directions of the incident light 101 and the diffracted beam 102, it can be understood that after the incident light 101 passes through the LCPG, it is deflected to one side by a specific angle to obtain a negative first-order diffracted beam.

[0084] In another example, when the incident light of the LCPG is right-handed circularly polarized light, the diffracted beam consists only of a positive first-order diffraction beam. For example... Figure 2 As shown, the rotation direction of the electric field vector of the incident light 201 of the LCPG is the direction indicated by arrow c (clockwise when facing the direction from which the beam is emitted), which indicates that the incident light is right-handed circularly polarized light. After the incident light 201 passes through the LCPG, a diffracted beam 202 can be formed. The rotation direction of the electric field vector of the diffracted beam 202 can be the direction indicated by arrow d, which indicates that the diffracted beam is left-handed circularly polarized light.

[0085] By comparing the beam directions of the incident light 201 and the diffracted beam 202, it can be understood that after the incident light 201 passes through the LCPG, it is deflected to the other side by a specific angle to obtain a positive first-order diffracted beam.

[0086] Furthermore, to achieve dynamic switching of the diffracted beam between the positive and negative orders, a phase-tunable liquid crystal waveplate can be introduced into the incident optical path of the liquid crystal polarization grating. (See also...) Figure 3 To understand, Figure 3 This is a schematic diagram of an LCPG unit provided in an embodiment of this application.

[0087] like Figure 3 As shown, the LCPG unit may include a phase-tunable liquid crystal waveplate and an LCPG plate. For example, the incident beam 301 first reaches the liquid crystal waveplate 301. When the incident beam is circularly polarized, by adjusting the phase delay of the beam by the liquid crystal waveplate, the polarization state of the outgoing beam 203 emitted from the liquid crystal waveplate can be adjusted, so that the outgoing beam 302 of the liquid crystal waveplate can switch between left-handed and right-handed circularly polarized light.

[0088] Subsequently, the outgoing beam 302 of the liquid crystal waveplate serves as the incident beam of the LCPG sheet, thereby controlling the diffracted beam of the liquid crystal polarization grating to switch between the deflection angles corresponding to the positive and negative orders, respectively. Specifically, when beam 302 is left-handed circularly polarized light, a diffracted beam 303 deflected to the deflection angle corresponding to the negative order can be obtained. Alternatively, when beam 302 is right-handed circularly polarized light, a diffracted beam 304 deflected to the deflection angle corresponding to the positive order can be obtained. For example, the LCPG sheet in the LCPG unit is a passive LCPG.

[0089] The time it takes for the light beam to switch between the deflection angle corresponding to the positive stage and the deflection angle corresponding to the negative stage, which is also the time it takes for the liquid crystal waveplate to switch different phase delays of the light beam, can be called the state switching time.

[0090] Typically, the phase retardation of a light beam by a liquid crystal waveplate is related to the driving voltage applied to the waveplate. In one implementation, the phase retardation of the light beam by the liquid crystal waveplate varies monotonically with the driving voltage applied to the waveplate, within a range between a threshold voltage and a saturation voltage.

[0091] If a DC voltage is used to drive the liquid crystal waveplate, the liquid crystal molecules in the waveplate will become polarized under a unidirectional electric field for a long time. To avoid polarization of the liquid crystal molecules in the waveplate, in some embodiments of this application, the driving voltage signal applied to the liquid crystal waveplate can be a square wave signal. It should be understood that in other embodiments, the driving voltage signal for the liquid crystal waveplate can also be a signal of other waveforms, such as: constant voltage signal, sine wave signal, triangular wave signal, sawtooth wave signal, stepped wave signal, etc., and the driving voltage value can be the absolute value, peak value, average value, effective value, etc. of the driving voltage signal.

[0092] Among them, the square wave signal is a periodically changing electrical signal. The waveform characteristics of the square wave signal are that it alternates between two fixed voltage values ​​(high level and low level) and jumps instantaneously. Its shape is similar to a series of rectangular waveforms, hence the name square wave.

[0093] In one example, a high level is, for example, P (in V), and a low level is, for example, -P (in V). In another example, a high level is, for example, P (in V), and a low level is, for example, 0 (in V).

[0094] The following example uses high level as P and low level as -P, combined with... Figure 4 Introducing the square wave signal, Figure 4 Schematic diagram of the implementation of the square wave signal provided in the embodiments of this application Figure 1 .

[0095] like Figure 4As shown, for example, the voltage value of a square wave signal transitions between P and -P. A square wave signal can repeat periodically; one period refers to the duration required for a complete cycle (e.g., high level → low level → high level).

[0096] For example in Figure 4 As shown in period T1, the voltage value of the square wave signal jumps from P to -P and then back to P. Then, in period T2, the voltage value of the square wave signal jumps from P to -P and then back to P again. Periods T3 and T4 are similar. Multiple periods repeating in sequence constitute the square wave signal.

[0097] The frequency of a square wave signal indicates the frequency of transitions between high and low levels. Based on the frequency of the square wave signal, the number of cycles completed per second can be determined. For example, the frequency of the square wave signal can be mkHz, where m is a value greater than 0. In this way, a large number of cycles can be completed per second. (See reference...) Figure 4 When observed on a normal time scale, the square wave signal, for example, presents the state shown in 401, that is, it completes multiple instantaneous transitions between the high level P and the low level -P.

[0098] The difference between the high level P and the low level -P is the peak-to-peak voltage (Vpp) of the square wave signal.

[0099] In some embodiments of this application, the driving voltage value applied to the liquid crystal molecules based on the square wave signal is also the peak-to-peak voltage value described herein.

[0100] Based on the implementation of square wave signals described above, the implementation of liquid crystal waveplates will be introduced below.

[0101] Assuming the phase retardation of the liquid crystal waveplate on the beam is φ_1, it corresponds to a positive first-order diffracted beam. The driving voltage value of the liquid crystal waveplate (specifically, the peak-to-peak voltage, which will not be elaborated further below) corresponding to the phase retardation of the beam by φ_1 is, for example, Vpp_1.

[0102] Furthermore, assuming the phase retardation of the liquid crystal waveplate to the beam is φ_2, it corresponds to the negative first order diffracted beam. When the phase retardation of the liquid crystal waveplate to the beam is φ_2, the corresponding driving voltage value of the liquid crystal waveplate is, for example, Vpp_2.

[0103] Generally, the difference between φ_1 and φ_2 is π. Accordingly, Vpp_1 and Vpp_2 are not equal, and we can assume that Vpp_1 > Vpp_2.

[0104] The following is combined with Figure 5 Further explanation of Vpp_1 and Vpp_2. Figure 5 Schematic diagram of the implementation of the square wave signal provided in the embodiments of this application Figure 2 .

[0105] In one implementation, a square wave signal containing multiple Vpp can be designed, such as... Figure 5 As shown, the voltage value of the square wave signal can jump between P and -P, with a corresponding peak-to-peak voltage of Vpp_1. Furthermore, the voltage value of the square wave signal can also jump between Q and -Q, with a corresponding peak-to-peak voltage of Vpp_2. Where Q is less than P, and Vpp_1 is greater than Vpp_2.

[0106] For example, the peak-to-peak voltage of a square wave signal can be set to repeat periodically between Vpp_1 and Vpp_2. For instance, in... Figure 5 In the illustration, the square wave signal can jump between P and -P within one cycle, between Q and -Q in the next cycle, between P and -P in the cycle after that, and so on.

[0107] The above description is only one possible approach. The specific setting of the multiple Vpp of the square wave signal depends on the phase adjustment requirements of the liquid crystal waveplate for the beam. Therefore, the specific design of the square wave signal can be set according to actual needs, and this application embodiment does not limit this.

[0108] As can be understood from the above description, if the driving voltage value is switched from Vpp_1 to Vpp_2, the phase delay of the liquid crystal waveplate on the beam is switched from φ_1 to φ_2, and the corresponding diffraction beam can be switched from the positive first stage to the negative first stage.

[0109] Conversely, if the driving voltage value is switched from Vpp_2 to Vpp_1, the phase delay of the liquid crystal waveplate on the beam is switched from φ_2 to φ_1, and the corresponding diffracted beam can be switched from the negative first order to the positive first order.

[0110] During voltage value switching, the circuit's response time is typically on the order of nanoseconds. That is, after receiving the switching command, the time required for the voltage value to change from Vpp_1 to Vpp_2, or from Vpp_2 to Vpp_1, is on the order of nanoseconds.

[0111] The phase retardation of the light beam by the liquid crystal waveplate is related to the orientation of the long axis of the liquid crystal molecules in the waveplate. After the voltage value is switched, the liquid crystal molecules in the waveplate rotate, and the orientation of the long axis of the liquid crystal molecules changes from one direction to another, thus changing the phase retardation of the light beam.

[0112] The phase retardation changes from φ_1 to φ_2 (corresponding to the liquid crystal molecule's long axis pointing from one direction to another), or the phase retardation changes from φ_2 to φ_1 (corresponding to the liquid crystal molecule's long axis pointing undergoing a directional switch opposite to the above). Since the transition described here requires the liquid crystal molecule to rotate from a stable state pointing along one direction to a stable state pointing along another direction, the time required (i.e., the state switching time described above) is usually on the order of sub-milliseconds to milliseconds.

[0113] Research has shown that the state switching time of the liquid crystal waveplate caused by switching its driving voltage from high to low is greater than the state switching time caused by switching from low to high. For example, the high voltage can be Vpp_1, and the low voltage can be Vpp_2.

[0114] You can refer to Figure 6 To understand, Figure 6 This application provides an example of a state switching implementation. Figure 1 .

[0115] like Figure 6 As shown, the waveform with serial number 1 corresponds to a square wave signal. For example, a square wave signal can contain two peak-to-peak voltages, Vpp_1 and Vpp_2. For instance, the peak-to-peak voltages of the square wave signal can switch periodically between Vpp_1 and Vpp_2.

[0116] Furthermore, waveform number 3 corresponds to the situation where the deflection angle of the light beam through the LCPG unit changes between the first deflection angle and the second deflection angle under the drive of the square wave signal number 1.

[0117] Combination Figure 6 It can be understood that when the peak-to-peak voltage of the square wave signal is Vpp_1, corresponding to the high-level state in the waveform, the long axis of the liquid crystal molecules in the liquid crystal waveplate points to the first direction under the drive of Vpp_1, so that the liquid crystal waveplate is in a stable first working state, the phase delay of the beam is φ_1, and the beam is modulated by the liquid crystal waveplate and then deflected to the first deflection angle by the LCPG plate.

[0118] When the peak-to-peak voltage of the square wave signal is Vpp_2, corresponding to the low-level state in the waveform, the long axis of the liquid crystal molecules in the liquid crystal waveplate points to the second direction under the drive of Vpp_2, so that the liquid crystal waveplate is in a stable second working state, the phase delay of the beam is φ_2, and the beam is modulated by the liquid crystal waveplate and then deflected to the second deflection angle by the LCPG plate.

[0119] Among them, the time it takes for the beam deflection angle to switch by the LCPG unit during the process of switching the driving voltage value from low level to high level is also known as... Figure 6 The "rise time" shown depends on the time required for the long axis of the liquid crystal molecules in the liquid crystal waveplate to switch from the second direction to the first direction and reach stability. For example, the average rise time is 1.112 ms.

[0120] The time it takes for the beam deflection angle to switch from high to low during the transition of the driving voltage from high to low is also known as the time it takes for the beam to change direction via the LCPG unit. Figure 6 The "fall time" shown depends on the time required for the long axis of the liquid crystal molecules in the liquid crystal waveplate to switch from a first direction to a second direction and reach stability. For example, the average fall time is 4.080 ms.

[0121] Therefore, combining Figure 6 As can be understood from the example, due to the different responses of the liquid crystal molecules in the liquid crystal waveplate to changes in the driving voltage, the state switching time of the liquid crystal waveplate corresponding to the different modulation states of the light beam caused by switching the driving voltage value of the liquid crystal waveplate from high voltage to low voltage is greater than the state switching time of the liquid crystal waveplate caused by switching from low voltage to high voltage.

[0122] To address the problems described above, this application proposes a control method for an LCPG unit to shorten the state switching time of the liquid crystal waveplate caused by the switching of the driving voltage value from high voltage to low voltage.

[0123] The technical solution of this application and how it solves the above-mentioned technical problems will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0124] First, combine Figure 7 The control method of the LCPG unit provided in the embodiments of this application will be introduced. Figure 7 Flowchart of the control method for the LCPG unit provided in the embodiments of this application Figure 1 .

[0125] like Figure 7 As shown, the method includes:

[0126] S701. When driving the liquid crystal waveplate based on the first voltage value, the first voltage value is adjusted to a second voltage value, where the second voltage value is less than the first voltage value.

[0127] In this embodiment of the application, for example, it is necessary to adjust the driving voltage value of the liquid crystal waveplate from a first voltage value to a third voltage value, where the third voltage value is less than the first voltage value, that is, it is necessary to reduce the driving voltage value of the liquid crystal waveplate.

[0128] In one implementation, when driving the liquid crystal waveplate based on a first voltage value, if it is necessary to adjust the driving voltage value of the liquid crystal waveplate from the first voltage value to a third voltage value, the first voltage value can be adjusted to a second voltage value first, wherein the second voltage value is less than the first voltage value and also less than the third voltage value.

[0129] The relationship between these three voltage values ​​is: first voltage value > third voltage value > second voltage value.

[0130] S702. After maintaining the second voltage value for a first duration, the liquid crystal waveplate is driven to a third voltage value; wherein the third voltage value is less than the first voltage value but greater than the second voltage value.

[0131] After adjusting the first voltage value to the second voltage value, the second voltage value can be maintained for a certain period of time. After the duration of maintaining the second voltage value reaches the first duration, the third voltage value is then adjusted to drive the liquid crystal waveplate, so as to achieve the purpose of adjusting the driving voltage value of the liquid crystal waveplate from the first voltage value to the third voltage value.

[0132] That is, in the implementation of adjusting the driving voltage value of the liquid crystal waveplate from the first voltage value to the third voltage value in the embodiments of this application, the first voltage value is first adjusted to a second voltage value that is lower than the third voltage value, and then the voltage is boosted from the second voltage value to the third voltage value.

[0133] In this process, the voltage change between the first and second voltage values ​​is greater than the voltage changes between the first and third voltage values, which can accelerate the deflection speed of the long axis of the liquid crystal molecules.

[0134] Therefore, adjusting the first voltage value to the second voltage value can accelerate the deflection of the long axis of the liquid crystal molecules in a direction different from the current orientation. Then, when the long axis of the liquid crystal molecules is close to the long axis orientation corresponding to the third voltage driving value, the driving voltage is adjusted back to the third voltage value, so that the liquid crystal molecules are stabilized in the long axis orientation corresponding to the third voltage value driving value.

[0135] Therefore, it is possible to shorten the state switching time of the liquid crystal waveplate caused by switching the voltage driving the liquid crystal waveplate from the first voltage value (i.e., high voltage) to the third voltage value (i.e., low voltage).

[0136] The driving voltage value of the liquid crystal waveplate is, for example, the peak-to-peak voltage value Vpp of a square wave signal, which is the same signal used to drive the liquid crystal waveplate as described in the above embodiments. Driving the liquid crystal waveplate based on the peak-to-peak voltage value of the square wave signal can prevent the liquid crystal molecules in the liquid crystal waveplate from becoming polarized under a unidirectional electric field for a long time.

[0137] For example, the first voltage value corresponds to Vpp_1 described in the above embodiments, and the third voltage value corresponds to Vpp_2 described in the above embodiments. Furthermore, the square wave signal in this embodiment may also have a peak-to-peak voltage value of Vpp_3 (corresponding to the second voltage value).

[0138] You can refer to Figure 8 To understand, Figure 8 This application provides an example of a state switching implementation. Figure 2 .

[0139] Figure 8 Understanding and Figure 6 Similarly, the waveform with serial number 1 corresponds to a square wave signal, and the waveform with serial number 3 corresponds to the situation where the deflection angle of the light beam through the LCPG unit changes between the first deflection angle and the second deflection angle under the drive of the square wave signal with serial number 1. The similarities will not be repeated in this embodiment.

[0140] Reference Figure 8 In this embodiment of the application, when it is necessary to adjust the peak-to-peak voltage value of the driving liquid crystal waveplate from Vpp_1 (first voltage value) to Vpp_2 (third voltage value), Vpp_1 (first voltage value) can be adjusted to Vpp_3 (second voltage value) first, and after maintaining Vpp_3 (second voltage value) for a first duration, the peak-to-peak voltage value of the driving liquid crystal waveplate can be adjusted to Vpp_2 (third voltage value).

[0141] As can be understood from the above description, when the peak-to-peak voltage of the driving liquid crystal waveplate is adjusted from Vpp_1 (first voltage value) to Vpp_2 (third voltage value), the deflection angle of the beam after being modulated by the liquid crystal waveplate and then by the LCPG plate will switch from the first deflection angle to the second deflection angle.

[0142] Furthermore, in the current embodiment, the peak-to-peak voltage of the driving liquid crystal waveplate is first adjusted from Vpp_1 (first voltage value) to Vpp_3 (second voltage value) so that the long axis of the liquid crystal molecules is deflected faster in a direction different from the current long axis direction. The corresponding light beam is also deflected faster after being modulated by the liquid crystal waveplate and then deflected by the LCPG plate.

[0143] Then, the peak-to-peak voltage of the driving liquid crystal waveplate is adjusted to Vpp_2 (the third voltage value) so that the liquid crystal molecules are stably aligned with the long axis under the drive of Vpp_2 (the third voltage value). The deflection angle of the corresponding beam after being modulated by the liquid crystal waveplate and then passing through the LCPG plate will also be maintained at the second deflection angle, thereby achieving the adjustment of the beam deflection angle.

[0144] Similar to the above, the time it takes for the beam deflection angle to switch by the LCPG unit during the switching of the driving voltage value from low to high is also... Figure 8 The rise time is shown. For example, the average rise time is 1.052 ms.

[0145] The time it takes for the beam deflection angle to switch from high to low during the transition of the driving voltage from high to low is also known as the time it takes for the beam to change direction via the LCPG unit. Figure 8 The "fall time" is shown. For example, the average fall time is 1.379 ms.

[0146] contrast Figure 6 and Figure 8 The example illustrates that, in the process of switching the driving voltage value of the liquid crystal waveplate from a first voltage value (i.e., high voltage) to a third voltage value (i.e., low voltage), the first voltage value is first switched to a second voltage value (a voltage value lower than low voltage). After maintaining the second voltage value for a certain period of time, the third voltage value is then adjusted to drive the liquid crystal waveplate. In this way, the state switching time of the liquid crystal waveplate caused by switching from high voltage to low voltage can be effectively shortened.

[0147] In one possible implementation, for example, the range of the second voltage value is 0V to KmV, where K is a value greater than or equal to 1. The specific value of K can be arbitrarily set according to actual needs, and this embodiment does not limit it.

[0148] In one example, K can take any of the following values: 10, 30, 50, 80, 100, 150, or 300. However, it's important to understand that the values ​​of K are not limited to those described here and can be extended according to actual needs.

[0149] Based on this, it can be understood that as long as the second voltage value is less than the first voltage value and less than the third voltage value, the state switching time of the liquid crystal plate caused by switching from high voltage to low voltage can be shortened. However, it can be further understood that the smaller the second voltage value, the greater the voltage change between the first and second voltage values ​​compared to the voltage changes of the first and third voltage values. This means that the liquid crystal molecules deflect their long axis in a direction different from their current long axis orientation more quickly.

[0150] Therefore, in a specific example, the second voltage value can be set to 0V to effectively shorten the state switching time of the liquid crystal plate caused by switching from high voltage to low voltage. The closer the second voltage value is to 0V, the more significant the reduction in state switching time.

[0151] The implementation details for the first duration will be introduced below.

[0152] In this embodiment, when the liquid crystal waveplate is driven based on a first voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate points in a first direction, so that the liquid crystal waveplate is in a stable first working state. Correspondingly, the phase delay of the light beam by the liquid crystal waveplate is φ_1, and the light beam can be deflected to a first deflection angle after being modulated by the liquid crystal waveplate and then by the LCPG plate.

[0153] When the liquid crystal waveplate is driven by the third voltage value, the long axis of the liquid crystal molecules in the waveplate points in the second direction, so that the liquid crystal waveplate is in a stable second working state. Correspondingly, the phase delay of the light beam by the liquid crystal waveplate is φ_2, and the light beam can be deflected to the second deflection angle after being modulated by the liquid crystal waveplate and then by the LCPG plate.

[0154] If the driving voltage of the liquid crystal waveplate is directly adjusted from a first voltage value to a third voltage value, and the time required to maintain the third voltage value so that the long axis orientation of the liquid crystal molecules in the waveplate changes from the first direction to the second direction is, for example, a second time duration, this change in the long axis orientation of the liquid crystal molecules will correspondingly cause a change in the phase delay of the light beam, thereby adjusting the deflection angle of the light beam after being modulated by the liquid crystal waveplate and then by the LCPG plate. Corresponding to the above... Figure 6 In the example, the second duration is the duration required for the waveform in sequence 3 to switch from the first deflection angle of the high level to the second deflection angle of the low level.

[0155] In this embodiment, the first duration can be set to be shorter than the second duration. The first duration can be understood as the time required for the long axis of the liquid crystal molecules to accelerate from the first direction corresponding to the first voltage value to the second direction corresponding to the third voltage value during the period of maintaining the second voltage value. Since switching the first voltage value to the second voltage value first can accelerate the rotation of the liquid crystal molecules, compared with directly adjusting the first voltage value to the third voltage value, the long axis of the liquid crystal molecules can rotate to the second direction faster during the period of switching to the second voltage value and maintaining it, and the time required is shorter than the second duration. This achieves the purpose of shortening the state switching time of the liquid crystal waveplate caused by switching the voltage driving the liquid crystal waveplate from the first voltage value (i.e., high voltage) to the third voltage value (i.e., low voltage).

[0156] Based on this design principle, the specific setting of the first duration can be determined according to the experiment.

[0157] The above embodiments introduced the relevant implementation of switching the driving voltage value of the liquid crystal waveplate from high voltage to low voltage. The following will introduce the relevant implementation of switching the driving voltage value of the liquid crystal waveplate from low voltage to high voltage.

[0158] Figure 9 Flowchart of the control method for the LCPG unit provided in the embodiments of this application Figure 2 .

[0159] like Figure 9 As shown, the method includes:

[0160] S901. When driving the liquid crystal wave plate based on the fourth voltage value, the voltage driving the liquid crystal wave plate is directly adjusted to the fifth voltage value, which is higher than the fourth voltage value.

[0161] In this embodiment of the application, for example, it is necessary to adjust the driving voltage value of the liquid crystal waveplate from the fourth voltage value to the fifth voltage value. The fifth voltage value is higher than the fourth voltage value, that is, it is necessary to increase the driving voltage value of the liquid crystal waveplate.

[0162] As explained above, there is no issue of excessive time consumption in scenarios requiring a higher driving voltage. Therefore, the driving voltage for the liquid crystal waveplate can be directly adjusted from the fourth voltage value to the fifth voltage value.

[0163] In one example, the fourth voltage value can be equal to the third voltage value, and the fifth voltage value can be equal to the first voltage value. That is to say, the scenario of increasing the driving voltage value described in the current embodiment corresponds to the scenario of decreasing the driving voltage value described above.

[0164] Similarly, in scenarios where the driving voltage of the liquid crystal waveplate is directly adjusted from a third voltage value to a first voltage value, for example, maintaining the first voltage value so that the time required for the long axis orientation of the liquid crystal molecules in the liquid crystal waveplate to change from the second direction to the first direction is the third time, the change in the long axis orientation of the liquid crystal molecules will correspondingly cause a change in the phase delay of the light beam, thereby adjusting the deflection angle of the light beam after being modulated by the liquid crystal waveplate and then by the LCPG plate. Corresponding to the above... Figure 6 In the example, the third duration, which is the duration required for the waveform in sequence 3 to switch from the second deflection angle of the low level to the first deflection angle of the high level.

[0165] Alternatively, the fourth voltage value may not be equal to the third voltage value, and the fifth voltage value may not be equal to the first voltage value. In other words, the high and low voltages in scenarios where the driving voltage value is increased can be different from those in scenarios where the driving voltage value is decreased.

[0166] It can be understood that the driving voltage value of the liquid crystal waveplate corresponds to the long axis orientation of the liquid crystal molecules, so that the liquid crystal waveplate can generate a corresponding phase delay for the passing light beam.

[0167] In one implementation, when the liquid crystal waveplate is driven based on a fourth voltage value, the long axis of the liquid crystal molecules in the waveplate points in a third direction, thereby placing the liquid crystal waveplate in a stable third operating state. Furthermore, when the liquid crystal waveplate is driven based on a fifth voltage value, the long axis of the liquid crystal molecules in the waveplate points in a fourth direction, thereby placing the liquid crystal waveplate in a stable fourth operating state.

[0168] In one example, the driving voltage value of the liquid crystal waveplate is directly adjusted from the fourth voltage value to the fifth voltage value (that is, the scenario of directly increasing the driving voltage value). For example, the time required to maintain the fifth voltage value so that the long axis of the liquid crystal molecules in the liquid crystal waveplate changes from the third direction to the fourth direction is the fourth time.

[0169] In another example, the driving voltage value of the liquid crystal waveplate is directly adjusted from the fifth voltage value to the fourth voltage value (that is, the scenario of directly reducing the driving voltage value). For example, the time required to maintain the fourth voltage value so that the long axis of the liquid crystal molecules in the liquid crystal waveplate changes from the third direction to the fourth direction is the fifth time.

[0170] exist Figure 6 and Figure 8 In the diagram, the time it takes for the beam deflection angle of the LCPG unit to switch from a low level to a high level corresponds to the "rise time" in the diagram. Similarly, the time it takes for the beam deflection angle of the LCPG unit to switch from a high level to a low level corresponds to the "fall time" in the diagram.

[0171] Reference Figure 6 It can be understood that the average time required to directly decrease the drive voltage value is, for example, 4.080 ms as shown in the figure, while the average time required to directly increase the drive voltage value is, for example, 1.112 ms as shown in the figure. This indicates that the time required to directly increase the drive voltage value is significantly less than the time required to directly decrease the drive voltage value.

[0172] and reference Figure 8 It is understandable that, in scenarios where a lower drive voltage value is set during descent, the average time required to decrease the drive voltage value is, for example, 1.379 ms as shown in the figure, and the average time required to directly increase the drive voltage value is, for example, 1.052 ms as shown in the figure. This indicates that, in scenarios where a lower drive voltage value is set during descent, the time required to directly increase the drive voltage value is also less than the time required to decrease the drive voltage value.

[0173] and comparison Figure 6 and Figure 8 It's understandable. Figure 8 The time required to directly increase the driving voltage value is less than Figure 6The time required to directly increase the drive voltage value indicates that the time required to directly increase the drive voltage value is not only significantly less than the time required to directly decrease the drive voltage value, but also less than the time required to decrease the drive voltage value in a scenario where a lower drive voltage value is set during the decrease.

[0174] That is, in this embodiment, the fourth duration is shorter than the fifth duration, meaning that the state switching time of the liquid crystal waveplate corresponding to directly increasing the driving voltage value is significantly shorter than the state switching time of the liquid crystal waveplate corresponding to directly decreasing the driving voltage value. Therefore, in step S901 of the above-mentioned LCPG unit control method, when the state switching of the liquid crystal waveplate requires increasing the applied driving voltage, the driving voltage can be directly adjusted from the lower fourth voltage value to the higher fifth voltage value.

[0175] As can be understood from the above description, the driving voltage value of the liquid crystal waveplate and the phase delay of the liquid crystal waveplate on the light beam are corresponding. Under different driving voltage values, the liquid crystal waveplate generates different phase delays on the light beam.

[0176] Furthermore, the LCPG plate in the LCPG unit can deflect the incident beam after it has been modulated by the liquid crystal waveplate, thereby achieving the purpose of switching the diffracted beam of the liquid crystal polarization grating between the positive and negative orders by combining the liquid crystal waveplate and the LCPG.

[0177] For example, the driving voltage of the liquid crystal waveplate can be adjusted according to the desired beam deflection angle.

[0178] The control method for the LCPG unit according to the embodiments of this application has been described above. The apparatus for executing the above method provided in the embodiments of this application is described below. Those skilled in the art will understand that the methods and apparatus can be combined with and referenced by each other, and the related apparatus provided in the embodiments of this application can execute the steps in the control method for the LCPG unit described above.

[0179] This application also provides a control module for an LCPG unit. Figure 10 This is a schematic diagram of the control module of the LCPG unit provided in an embodiment of this application.

[0180] like Figure 10 As shown, the control module 100 provided in this embodiment includes at least one processor 1001 and a memory 1002. Optionally, the device 100 further includes a bus 1003. The processor 1001 and the memory 1002 are connected via the bus 1003.

[0181] In a specific implementation, at least one processor 1001 executes computer execution instructions stored in memory 1002, causing at least one processor 1001 to perform the above-described method.

[0182] The specific implementation process of processor 1001 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0183] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0184] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0185] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0186] This application also provides an LCPG unit. Figure 11 This is a schematic diagram of the structure of the LCPG unit provided in an embodiment of this application.

[0187] like Figure 11 As shown, the LCPG unit 110 provided in this embodiment includes: a liquid crystal waveplate 1101, at least one LCPG sheet 1102, and the control module 100 described above. The LCPG unit 110 adjusts the driving voltage value of the liquid crystal waveplate 1101 through the control module 100 to switch different modulation states of the light beam by the liquid crystal waveplate 1101, thereby switching the deflection angle of the modulated light beam through the LCPG sheet 1102. Exemplarily, the LCPG sheet is a passive LCPG.

[0188] This application also provides an optical deflection device. Figure 12 This is a schematic diagram of the structure of the optical deflection device provided in the embodiments of this application.

[0189] like Figure 12 As shown, the optical deflection device 120 provided in this embodiment includes multiple cascaded LCPG units, wherein the LCPG units can be referred to as Figure 11 The introduction and understanding. For example, in Figure 12 In the schematic diagram, the light deflecting device 120 may include cascaded LCPG units 110_1, LCPG unit 110_2, ..., LCPG unit 110_n, where n is an integer greater than or equal to 1. Multiple cascaded LCPG units can sequentially deflect a passing light beam to achieve a larger deflection angle range and more deflection angles. Similarly, the light deflecting device 120 can control the driving voltage value of the liquid crystal waveplate on each LCPG unit to sequentially deflect the light beam at different angles.

[0190] This application also provides a lidar, Figure 13 This is a schematic diagram of the structure of a lidar provided in an embodiment of this application.

[0191] like Figure 13 As shown, the lidar 130 provided in this embodiment includes a transmitting module 131 and a receiving module 132. The transmitting module 131 and / or the receiving module 132 include the LCPG unit 110 or the optical deflection device 120 described in the above embodiment.

[0192] That is, it includes the following three situations:

[0193] Case 1: The transmitting module 131 includes an LCPG unit 110 or an optical deflection device 120;

[0194] Case 2: The receiving module 132 includes an LCPG unit 110 or an optical deflection device 120;

[0195] Case 3: Both the transmitting module 131 and the receiving module 132 include an LCPG unit 110 or an optical deflection device 120.

[0196] Reference Figure 13 The transmitting module 131 includes a light source 1311, which can deflect the light beam emitted by the light source 1311 to different fields of view for scanning via the LCPG unit 110 or the light deflection device 120.

[0197] The receiving module 132 includes a sensing chip 1321, which can deflect light beams from different orientations of the field of view to the corresponding sensing pixels on the sensing chip 1321 for sensing via the LCPG unit 110 or the light deflection device 120. For example, the sensing chip is a single-photon avalanche diode (SPAD) array chip.

[0198] This application also provides an electronic device. Figure 14 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0199] like Figure 14 As shown, the electronic device 140 provided in this embodiment includes a lidar 130. The lidar 130 is used to sense spatial information of the environment in which the electronic device 140 is located. For example, the electronic device 140 may be a car, an autonomous vehicle, a robot, a drone, etc.

[0200] This application also provides a computer-readable storage medium. Figure 15 This is a schematic diagram of the structure of a computer-readable storage medium provided in an embodiment of this application.

[0201] like Figure 15 As shown, the computer-readable storage medium 150 stores computer-executable instructions, which, when executed by the processor, implement the above-described method.

[0202] The aforementioned computer-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The computer-readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0203] For example, a computer-readable storage medium may be coupled to a processor, enabling the processor to read information from and write information to the computer-readable storage medium. Of course, the computer-readable storage medium can also be a component of the processor. The processor and the computer-readable storage medium may reside in an application-specific integrated circuit (ASIC). Alternatively, the processor and the computer-readable storage medium may exist as discrete components in the device.

[0204] This application also provides a computer program product. Figure 16This is a schematic diagram of the structure of a computer program product provided in an embodiment of this application.

[0205] like Figure 16 As shown, computer program product 160 includes a computer program that, when executed by a processor, implements the methods described above.

[0206] It should also be understood that the unit division described in the above embodiments is merely a logical functional division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0207] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0208] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0209] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0210] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0211] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A control method for an LCPG unit, characterized in that, Applied to an LCPG cell, the LCPG cell comprising a liquid crystal waveplate; the method includes: When driving the liquid crystal waveplate based on a first voltage value, the first voltage value is adjusted to a second voltage value, wherein the second voltage value is less than the first voltage value; After maintaining the second voltage value for a first duration, the liquid crystal waveplate is driven by adjusting to a third voltage value; wherein the third voltage value is less than the first voltage value but greater than the second voltage value.

2. The method according to claim 1, characterized in that, The second voltage value falls within the range of 0V to KmV, where K is a value greater than or equal to 1.

3. The method according to claim 2, characterized in that, The value of K can be any of the following: 10, 30, 50, 80, 100, 150, 300.

4. The method according to claim 2, characterized in that, The second voltage value is equal to 0V.

5. The method according to any one of claims 1-4, characterized in that, The driving voltage value of the liquid crystal waveplate is the peak-to-peak voltage value of the square wave signal, which is used to drive the liquid crystal waveplate.

6. The method according to any one of claims 1-4, characterized in that, When the liquid crystal waveplate is driven based on the first voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate points in the first direction, so that the liquid crystal waveplate is in a stable first working state. When the liquid crystal waveplate is driven based on the third voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate points in the second direction, so that the liquid crystal waveplate is in a stable second working state.

7. The method according to claim 6, characterized in that, The driving voltage value of the liquid crystal waveplate is directly adjusted from the first voltage value to the third voltage value, and the third voltage value is maintained so that the time required for the long axis of the liquid crystal molecules in the liquid crystal waveplate to change from the first direction to the second direction is the second time, and the first time is less than the second time.

8. The method according to any one of claims 1-4, characterized in that, The method further includes: When driving the liquid crystal waveplate based on the fourth voltage value, the voltage driving the liquid crystal waveplate is directly adjusted to the fifth voltage value, which is higher than the fourth voltage value.

9. The method according to claim 8, characterized in that, The fourth voltage value is equal to the third voltage value, and the fifth voltage value is equal to the first voltage value.

10. The method according to claim 8, characterized in that, When the liquid crystal waveplate is driven based on the fourth voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate points to the third direction, so that the liquid crystal waveplate is in a stable third working state. When the liquid crystal waveplate is driven based on the fifth voltage value, the long axis of the liquid crystal molecules in the liquid crystal waveplate points to the fourth direction, so that the liquid crystal waveplate is in a stable fourth working state. Specifically, the driving voltage value of the liquid crystal waveplate is directly adjusted from the fourth voltage value to the fifth voltage value, and the fifth voltage value is maintained so that the time required for the long axis of the liquid crystal molecules in the liquid crystal waveplate to change from the third direction to the fourth direction is the fourth time duration; the driving voltage value of the liquid crystal waveplate is directly adjusted from the fifth voltage value to the fourth voltage value, and the fourth voltage value is maintained so that the time required for the long axis of the liquid crystal molecules in the liquid crystal waveplate to change from the fourth direction to the third direction is the fifth time duration, wherein the fourth time duration is less than the fifth time duration.

11. The method according to any one of claims 1-4, characterized in that, The LCPG unit further includes an LCPG sheet, which is used to deflect the incident light beam modulated by the liquid crystal waveplate; the method further includes: The driving voltage value of the liquid crystal waveplate is adjusted according to the desired beam deflection angle.

12. A control module for an LCPG unit, characterized in that, Memory and processor; The memory is configured to store computer-executed instructions; The processor is configured to execute computer execution instructions stored in the memory, causing the processor to perform the method as described in any one of claims 1-11.

13. An LCPG unit, characterized in that, include: A liquid crystal waveplate, at least one LCPG plate, and a control module for the LCPG unit as described in claim 12.

14. An optical deflection device, characterized in that, It includes multiple cascaded LCPG units as described in claim 13.

15. A lidar, characterized in that, This includes the LCPG unit as described in claim 13 or the optical deflection device as described in claim 14.

16. An electronic device, characterized in that, Including the lidar as described in claim 15.

17. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1-11.

18. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the method described in any one of claims 1-11.

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