A spatial light modulator driving device and a driving method

Abstract

The present invention discloses a spatial light modulator driving device and a driving method, comprising a main control unit, a signal conversion unit, a level conversion unit, a signal modulation unit, a signal driving unit, a power supply unit and an LCoS spatial light modulation unit; the main control unit is used for converting and adjusting the signal output by the signal conversion unit; the main control unit outputs a first digital signal, a second digital signal and a first control signal; the signal conversion unit is used for the reference input of the signal modulation unit; the signal conversion unit receives the first digital signal and the second digital signal, and generates a first pixel level signal and a first black field level signal; the level conversion unit is used for controlling the LCoS driving signal output by the modulation unit; compared with the prior art, the present invention can dynamically configure the driving level of the driving signal according to the driving requirements of the spatial light modulation unit, the driving mode is more flexible, can adapt to different types of LCoS products, and has strong compatibility.

Description

Technical Field

[0001] The present invention relates to the field of novel displays, and in particular to a spatial light modulator driving device and a driving method. Background Art

[0002] In recent years, spatial light modulators have been widely used. They are based on liquid crystal on silicon (LCoS). Under the control of time-varying electrical drive signals and other signals, spatial light modulators can change the amplitude, polarization state or phase of light distribution in space, or convert incoherent light into coherent light. They can easily write specific information into light waves to achieve the purpose of light wave modulation. Different from the transmission technology of traditional LCD display, the spatial light modulator based on LCoS adopts a reflective light modulation scheme to display images by modulating liquid crystal molecules and reflecting silicon wafers. Since LCoS can spatially modulate light waves of different bands, it has a wide range of applications in optical communications, laser processing, holographic display and other fields. Most of the existing LCoS spatial light modulation methods are analog modulation methods. Although the technology is relatively mature, the modulation resolution is limited. Digital modulation can achieve higher resolution and larger panels, as well as higher signal-to-noise ratio and model stability. The existing digital modulation driving scheme based on LCoS spatial light modulator usually adopts level shifting circuit to realize the flipping control of silicon-based liquid crystal because it needs to generate positive and negative level driving signals. This method cannot dynamically adjust the level of the driving signal, and cannot achieve fast response for high-speed signal transmission requirements, and is prone to signal distortion. Summary of the invention

[0003] The purpose of the present invention is to address the problems that the existing spatial light modulator cannot dynamically adjust the level of the driving signal, cannot achieve fast response to the requirements of higher-speed signal transmission, and is prone to signal distortion. To address this problem, a spatial light modulator driving device and driving method are proposed.

[0004] In order to achieve the above object, the present invention adopts the following technical solution:

[0005] A spatial light modulator driving device comprises a main control unit, a signal conversion unit, a level conversion unit, a signal modulation unit, a signal driving unit, a power supply unit and an LCoS spatial light modulation unit;

[0006] Wherein, the main control unit is used to convert and adjust the signal output by the signal conversion unit; the main control unit outputs a first digital signal, a second digital signal and a first control signal;

[0007] The signal conversion unit is used as a reference input of the signal modulation unit; the signal conversion unit receives the first digital signal and the second digital signal, and generates a first pixel level signal and a first black field level signal; the first pixel level signal and the first black field level signal are dynamically adjustable, and the main controller controls and configures the signal conversion unit;

[0008] The level conversion unit is used to control the driving signal of the LCoS output by the signal modulation unit; the level conversion unit receives the first control signal output by the main control unit and converts the level into the second control signal.

[0009] The signal modulation unit receives the first pixel level signal and the first black field level signal, and under the control of the second control signal, realizes the output of the positive and negative level digital driving signal, and the signal modulation unit outputs the first modulation signal and the second modulation signal;

[0010] The signal driving unit is used to increase the driving capability of the signal and output a third pixel level signal and a second driving signal;

[0011] The power supply unit is used to generate different voltages and provide them to each functional unit to ensure the normal and stable operation of the unit;

[0012] The LCoS spatial light modulation unit receives the third pixel level signal and the second driving signal to modulate the spatial light.

[0013] As a further preferred embodiment of the present invention, the signal driving unit includes a first driving unit, a second driving unit, a third driving unit and a fourth driving unit; the first driving unit, the second driving unit, the third driving unit and the fourth driving unit each include a positive phase input terminal, a negative phase input terminal, positive and negative power supply input terminals and an output terminal;

[0014] The positive phase input terminal of the first driving unit is connected to the port of the signal conversion unit outputting the first pixel level signal, the negative phase input terminal is connected to the port of the signal conversion unit outputting the first black field level signal, and the output terminal outputs the second pixel level signal and is connected to the signal modulation unit;

[0015] The positive phase input terminal of the second driving unit is connected to the port of the signal modulation unit outputting the first modulation signal, the negative phase input terminal is connected to the port of the signal modulation unit outputting the second modulation signal, and the output terminal outputs the first driving signal, which is connected to the positive phase input terminal of the third driving unit;

[0016] The output end of the third driving unit outputs a second driving signal, which is connected to the LCoS spatial light modulation unit to realize modulation and driving of the spatial light;

[0017] The positive phase input terminal of the fourth driving unit is connected to the first pixel level signal port output by the signal conversion unit, and the output terminal outputs a third pixel level signal, which is connected to the LCoS spatial light modulation unit and is used as a pixel reference level of the LCoS spatial light modulator unit.

[0018] As a further preferred embodiment of the present invention, the signal modulation unit includes a signal control input terminal, a first data input terminal, a second data input terminal, a third data input terminal, a first data output terminal and a second data output terminal;

[0019] Among them, the signal control input end is connected to the level conversion unit, the first data input end is connected to the output end of the first driving unit, the second data input end is connected to the port of the signal conversion unit outputting the first pixel level signal, the third data input end is connected to the port of the signal conversion unit outputting the first black field level signal, the first data output end outputs the first modulation signal and is connected to the positive phase input end of the second driving unit, and the second data output end outputs the second modulation signal and is connected to the negative phase input end of the second driving unit.

[0020] As a further preferred embodiment of the present invention, the main control unit includes an FPCA chip, the signal conversion unit includes a first DAC digital-to-analog converter and a second DAC digital-to-analog converter; the FPCA chip is connected to the first DAC digital-to-analog converter and the second DAC digital-to-analog converter through an SPI serial port, the level conversion unit is connected through the SPI serial port FPCA chip, the signal modulation unit includes a multi-way signal selector, and the signal driving unit includes a first operational amplifier, a second operational amplifier, a third operational amplifier and a fourth operational amplifier; the first DAC digital-to-analog converter is connected to the positive phase input terminal of the first operational amplifier through a resistor, and the first DAC digital-to-analog converter is connected to the IN3 pin of the multi-way signal selector; the second DAC digital-to-analog converter is connected to the negative phase input terminal of the first operational amplifier through a resistor, and the second DAC digital-to-analog converter is connected to the IN2 pin of the multi-way signal selector; the positive phase input terminal of the first operational amplifier is connected to the output terminal of the first operational amplifier, and the negative phase input terminal of the first operational amplifier is connected to the IN4 pin of the multi-way signal selector; The phase input terminal is grounded through a resistor, and the output terminal of the first operational amplifier is connected to the IN1 pin of the multiplexer; the level conversion unit is connected to the CTL pin of the multiplexer; the IN4 pin of the multiplexer is grounded; the OUT2 pin of the multiplexer is connected to the positive phase input terminal of the second operational amplifier, the OUT1 pin of the multiplexer is connected to the negative phase input terminal of the second operational amplifier through a resistor, the negative phase input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier through a resistor, and the output terminal of the second operational amplifier is connected to the positive phase input terminal of the third operational amplifier; the negative phase input terminal of the third operational amplifier is connected to the output terminal of the third operational amplifier through a resistor, and the output terminal of the third operational amplifier is connected to the LCoS spatial light modulation unit; the second DAC digital-to-analog converter is connected to the positive phase input terminal of the fourth operational amplifier, the negative phase input terminal of the fourth operational amplifier is connected to the output terminal of the fourth operational amplifier through a resistor, and the output terminal of the fourth operational amplifier is connected to the LCoS spatial light modulation unit;

[0021] As a further preferred embodiment of the present invention, the amplitude of the first pixel level signal is greater than the amplitude of the first black field level signal.

[0022] As a further preferred embodiment of the present invention, the first control signal and the second control signal have the same frequency and the same low level amplitude; the high level of the first control signal is a first amplitude and is determined by the main control unit; the high level of the second control signal is a second amplitude and is determined by the level conversion unit through the interface level of the signal modulation unit.

[0023] As a further preferred embodiment of the present invention, the first modulation signal and the second modulation signal are determined by the high and low levels of the second control signal;

[0024] When the second control signal is at a high level, the first modulation signal is the difference between the first pixel level signal and the first black field level signal, and the second modulation signal is the first pixel level signal;

[0025] When the second control signal is at a low level, the first modulation signal is a first black field level signal, and the second modulation signal is 0V.

[0026] As a further preferred embodiment of the present invention, the first drive signal and the second drive signal are set to PWM square wave signals, the frequencies of the first drive signal and the second drive signal are the same as the frequency of the first control signal, the low level of the second drive signal is the negative value of the first black field level signal, the high level of the second drive signal is the sum of the first pixel level signal and the first black field level signal, and the driving capability of the second drive signal is better than that of the first drive signal.

[0027] As a further preferred embodiment of the present invention, the third pixel level signal is a DC level signal, and the third pixel level signal has the same amplitude as the first pixel level signal, but has a greater driving capability than the first pixel level signal.

[0028] A spatial light modulator driving method comprises the following steps:

[0029] S1, the main control unit dynamically sets and controls the output of the first digital signal, the second digital signal and the first control signal through a program;

[0030] S2, a signal conversion unit receives the first digital signal and the second digital signal and generates a first pixel level signal and a first black field level signal respectively through analog-to-digital conversion;

[0031] S3, the level conversion unit receives the first control signal and generates a second control signal through level conversion;

[0032] S4, the first driving unit receives the first pixel level signal and the first black field level signal, and outputs a second pixel level signal, where the second pixel level signal is a difference between the first pixel level signal and the first black field level signal;

[0033] S5, the signal modulation unit receives the first pixel level signal, the second pixel level signal and the first black field level signal, and outputs the first modulation signal and the second modulation signal under the action of the second control signal; if the second control signal is at a high level, the high level of the first modulation signal and the high level of the second modulation signal are output; if the second control signal is at a low level, the low level of the first modulation signal and the low level of the second modulation signal are output;

[0034] S6. The second driving unit receives the first modulation signal and the second modulation signal, and outputs the first driving signal according to the difference in the level values ​​of the first modulation signal and the second modulation signal. The level of the first driving signal is the difference between twice the second modulation signal and the first modulation signal. The first driving signal is a PWM signal, which has the same phase as the second control signal. The level amplitude of the first driving signal is adjusted in real time according to the level flipping of the second control signal; that is, the first driving signal adjusts the level of the first driving signal in real time following the flipping of the second control signal;

[0035] S7, the third driving unit receives the first driving signal and outputs a second driving signal, the second driving signal has the same phase and level amplitude as the first driving signal, and the driving capability is better than the first driving signal;

[0036] S8, the fourth driving unit receives the first pixel level signal and generates a third pixel level signal. The third pixel level signal has the same level as the first pixel level signal and has a better driving capability than the first pixel level signal;

[0037] S9. The LCoS spatial light modulation unit receives the second driving signal and the fourth pixel level signal to modulate the spatial light.

[0038] Compared with the prior art, the spatial light modulator driving device and driving method proposed in the present invention have the following beneficial effects:

[0039] 1. The spatial light modulation driving device of the present invention can dynamically configure the driving level of the driving signal according to the driving requirements of the spatial light modulation unit. The driving mode is more flexible and can adapt to different types of LCoS products with strong compatibility.

[0040] 2. The spatial light modulation driving device of the present invention adjusts the level of the first driving signal in real time according to the level flipping of the control signal, which can realize the real-time adjustment and response of the high-speed driving level signal, effectively improve the quality of the LCoS driving signal, and reduce the influence of signal distortion on the LCoS spatial light modulation;

[0041] 3. The present invention combines the main controller and the signal modulation unit, and adopts a digital control signal to control the positive and negative levels of the driving signal generated by the modulation unit, thereby solving the problem that the positive and negative level voltage difference of the traditional level shifting circuit cannot be adjusted, and can realize the generation of any positive and negative level voltage difference of the driving signal, and has wide applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a system block diagram of the present invention;

[0043] Figure 2 It is a schematic diagram of the module connection relationship of the present invention;

[0044] Figure 3 It is a circuit connection schematic diagram of the present invention.

[0045] The meanings of the reference numerals in the figure are as follows: 10, main control unit, 20, signal conversion unit, 30, level conversion unit, 40, signal modulation unit, 50, signal driving unit, 501, first driving unit, 502, second driving unit, 503, third driving unit, 504, fourth driving unit, 60, power supply unit, 70, LCoS spatial light modulation unit. DETAILED DESCRIPTION

[0046] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0047] Embodiment 1: Combination Figure 1-3 , a spatial light modulator driving device includes a main control unit 10, a signal conversion unit 20, a level conversion unit 30, a signal modulation unit 40, a signal driving unit 50, a power supply unit 60 and an LCoS spatial light modulation unit 70.

[0048] The main control unit 10 is used to convert and adjust the signal output by the signal conversion unit 20; the main control unit 10 outputs a first digital signal SPI1, a second digital signal SPI2 and a first control signal CMD1.

[0049] The signal conversion unit 20 is used for the reference input of the signal modulation unit 40; the signal conversion unit 20 receives the first digital signal SPI1 and the second digital signal SPI2, and generates a first pixel level signal VP1 and a first black field level signal VB1; the first pixel level signal VP1 and the first black field level signal VB1 are dynamically adjustable, and the signal conversion unit 20 is controlled and configured by the main controller; the amplitude of the first pixel level signal VP1 is greater than the amplitude of the first black field level signal VB1.

[0050] The level conversion unit 30 is used to control the driving signal of the LCoS output by the signal modulation unit; the level conversion unit 30 receives the first control signal CMD1 output by the main control unit 10, and converts the level into the second control signal CMD2; the first control signal CMD1 and the second control signal CMD2 have the same frequency and the same low level amplitude; the high level CMD1_H of the first control signal CMD1 is a first amplitude and is determined by the main control unit 10; the high level CMD2_H of the second control signal CMD2 is a second amplitude and is determined by the level conversion unit 30 through the interface level of the signal modulation unit 40.

[0051] The signal modulation unit 40 receives the first pixel level signal VP1 and the first black field level signal VB1, and realizes the output of the positive and negative level digital driving signal under the control of the second control signal CMD2, and the signal modulation unit 40 outputs the first modulation signal VT1 and the second modulation signal VT2; the signal modulation unit 40 includes a signal control input terminal CTL, a first data input terminal IN1, a second data input terminal IN2, a third data input terminal IN3IN4, a first data output terminal OUT1 and a second data output terminal OUT2. The signal control input terminal CTL is connected to the level conversion unit 30, the first data input terminal IN1 is connected to the output terminal of the first driving unit 501, the second data input terminal IN2 is connected to the port of the signal conversion unit outputting the first pixel level signal VP1, the third data input terminal IN3 is connected to the port of the signal conversion unit outputting the first black field level signal VB1, the first data output terminal OUT1 outputs the first modulation signal VT1, and is connected to the positive phase input terminal of the second driving unit 502, and the second data output terminal OUT2 outputs the second modulation signal VT2, and is connected to the negative phase input terminal of the second driving unit 502.

[0052] The first modulation signal VT1 and the second modulation signal VT2 are determined by the high and low levels of the second control signal CMD2; when the second control signal CMD2 is at a high level CMD2_H, the first modulation signal VT1 is the difference between the first pixel level signal VP1 and the first black field level signal VB1, and the second modulation signal VT2 is the first pixel level signal VP1; when the second control signal CMD2 is at a low level CMD2_L, the first modulation signal VT1 is the first black field level signal VB1, and the second modulation signal VT2 is 0V.

[0053] The signal driving unit 50 is used to increase the driving ability of the signal, and outputs a third pixel level signal VP3 and a second driving signal VD2; the signal driving unit 50 includes a first driving unit 501, a second driving unit 502, a third driving unit 503 and a fourth driving unit 504; the first driving unit 501, the second driving unit 502, the third driving unit 503 and the fourth driving unit 504 each include a positive phase input terminal, a negative phase input terminal, positive and negative power supply input terminals and an output terminal; wherein the positive phase input terminal of the first driving unit 501 is connected to the port of the signal conversion unit 20 outputting the first pixel level signal VP1, the negative phase input terminal is connected to the port of the signal conversion unit 20 outputting the first black field level signal VB1, and the output terminal outputs the second pixel level signal VP2, which is connected to the signal modulation unit 20. The positive phase input terminal of the second driving unit 502 is connected to the port of the signal modulation unit 40 outputting the first modulation signal VT1, the negative phase input terminal is connected to the port of the signal modulation unit 40 outputting the second modulation signal VT2, the output terminal is the first driving signal VD1, and is connected to the positive phase input terminal of the third driving unit 503; the output terminal of the third driving unit 503 outputs the second driving signal VD2, which is connected to the LCoS spatial light modulation unit 70 for realizing the modulation and driving of the spatial light; the positive phase input terminal of the fourth driving unit 504 is connected to the port of the signal conversion unit 20 outputting the first pixel level signal VP1, the output terminal outputs the third pixel level signal VP3, which is connected to the LCoS spatial light modulation unit 70 for serving as the pixel reference level of the LCoS spatial light modulator unit.

[0054] The first drive signal VD1 and the second drive signal VD2 are set as PWM square wave signals, the frequencies of the first drive signal VD1 and the second drive signal VD2 are the same as the frequency of the first control signal CMD1, the low level of the second drive signal VD2 is the negative value of the first black field level signal VB1, the high level of the second drive signal VD2 is the sum of the first pixel level signal VP1 and the first black field level signal VB1, and the driving ability of the second drive signal VD2 is better than the first drive signal VD1. The third pixel level signal VP3 is a DC level signal, and the third pixel level signal VP3 has the same amplitude as the first pixel level signal VP1, but the driving ability is greater than the first pixel level signal VP1.

[0055] The power supply unit 60 is used to generate different voltages to provide to each functional unit to ensure the normal and stable operation of the unit.

[0056] The LCoS spatial light modulation unit 70 receives the third pixel level signal VP3 and the second driving signal VD2 to modulate the spatial light.

[0057] The main control unit 10 includes an FPCA chip, and the signal conversion unit 20 includes a first DAC digital-to-analog converter and a second DAC digital-to-analog converter; the FPCA chip is connected to the first DAC digital-to-analog converter and the second DAC digital-to-analog converter through an SPI serial port, the signal conversion unit 20 includes a level conversion unit 30, which is connected to the FPCA chip through an SPI serial port, the signal modulation unit 40 includes a multi-way signal selector, and the signal driving unit 50 includes a first operational amplifier, a second operational amplifier, a third operational amplifier and a fourth operational amplifier; the first DAC digital-to-analog converter is connected to the positive phase input terminal of the first operational amplifier through a resistor, and the first DAC digital-to-analog converter is connected to the IN3 pin of the multi-way signal selector; the second DAC digital-to-analog converter is connected to the negative phase input terminal of the first operational amplifier through a resistor, and the second DAC digital-to-analog converter is connected to the IN2 pin of the multi-way signal selector; the positive phase input terminal of the first operational amplifier is connected to the output terminal of the first operational amplifier, and the first operational amplifier The negative phase input terminal is grounded through a resistor, and the output terminal of the first operational amplifier is connected to the IN1 pin of the multiplexer; the level conversion unit 30 is connected to the CTL pin of the multiplexer; the IN4 pin of the multiplexer is grounded; the OUT2 pin of the multiplexer is connected to the positive phase input terminal of the second operational amplifier, the OUT1 pin of the multiplexer is connected to the negative phase input terminal of the second operational amplifier through a resistor, the negative phase input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier through a resistor, and the output terminal of the second operational amplifier is connected to the positive phase input terminal of the third operational amplifier; the negative phase input terminal of the third operational amplifier is connected to the output terminal of the third operational amplifier through a resistor, and the output terminal of the third operational amplifier is connected to the LCoS spatial light modulation unit 70; the second DAC digital-to-analog converter is connected to the positive phase input terminal of the fourth operational amplifier, the negative phase input terminal of the fourth operational amplifier is connected to the output terminal of the fourth operational amplifier through a resistor, and the output terminal of the fourth operational amplifier is connected to the LCoS spatial light modulation unit 70.

[0058] Since the first pixel level signal VP1 and the first black field level signal VB1 are converted through digital-to-analog conversion, the digital-to-analog converter can be controlled to generate dynamically adjustable level values ​​and ranges according to the program settings of the main controller. The output level upper limit is determined by the power supply upper limit of the signal conversion unit 20, and the amplitude of the first pixel level signal VP1 is always greater than the amplitude of the first black field level signal VB1.

[0059] For example: the power supply level of the signal conversion unit 20 is 0V~+5.5V, the first pixel level signal VP1 is +5V, and the first black field level signal VB1 is +2V; the level and frequency of the first control signal CMD1 are configured by the main controller, the low level CMD1_L of the first control signal CMD1 is 0V, the high level CMD1_H is +1.8V, and the frequency is 10KHz; the second control signal CMD2 is a square wave signal after level conversion, wherein the low level CMD2_L is 0V, the high level is CMD2_H+5V, and the frequency is 10KHz.

[0060] The multiplexer, under the control of the second control signal CMD2, realizes the output control of different signals according to the high and low levels of the second control signal. The first modulation signal VT1 and the second modulation signal VT2 are determined by the high and low levels of the second control signal CMD2. When the second control signal CMD2 is at a high level, the first modulation signal VT1 is the difference between the first pixel level signal VP1 and the first black field level signal VB1, and the second modulation signal VT2 is the first pixel level signal VP1; when the second control signal CMD2 is at a low level, the first modulation signal VT1 is the first black field level signal VB1, and the second modulation signal VT2 is 0V.

[0061] For example, when the second control signal CMD2 is at a high level of +5V, the first modulation signal VT1 is +3V and the second modulation signal VT2 is +5V; when the second control signal CMD2 is at a low level of 0V, the first modulation signal VT1 is +2V and the second modulation signal VT2 is 0V. The first modulation signal VT1 and the second modulation signal VT2 are connected through the second signal driving unit 50 to generate the first driving signal VD1.

[0062] The level of the second pixel level signal VP2 is the difference between the first pixel level signal VP1 and the first black field level signal VB1, which is +3V; the second drive signal VD2 is used to drive the driving and modulation of the LCoS spatial light modulator; the first drive signal VD1 and the second drive signal VD2 are square wave signals, the frequency of the second drive signal VD2 is the same as the frequency of the first control signal CMD1, the low level of the second drive signal VD2 and the first drive signal VD1 is the negative value of the first black field level signal VB1, the high level is the sum of the first pixel level signal VP1 and the first black field level signal VB1, and the driving ability of the second drive signal VD2 is better than the first drive signal VD1; the third pixel level signal VP3 is used as a pixel reference level of the LCoS spatial light modulator unit, the driving ability of the third pixel level signal VP3 is better than the first pixel level signal VP1, and the level amplitudes of the two are the same.

[0063] The power supply voltage generated by the power supply unit 60 is mainly divided into two parts, a positive voltage and a negative voltage. The positive voltage part generates +5.5V required by the signal conversion unit 20, +1.8V and +5V required by the level conversion unit 30, +5V required by the signal modulation unit 40, and +6V required by the first driving unit 501 and the fourth driving unit 504 through the BUCK circuit; the negative voltage part mainly generates a -5V voltage through the charge pump circuit, which is used to provide to the signal modulation unit 40, the second driving unit 502 and the third driving unit 503; the positive and negative power supply terminals of the first driving unit 501 and the fourth driving unit 504 are +6V and 0V respectively, and the positive and negative power supply terminals of the second driving unit 502 and the third driving unit 503 are +10V and -5V respectively. The power supply terminal of the driving unit determines the maximum value of the positive and negative levels of the output signal. When the low level CMD2_L of the second control signal CMD2 is 0V, the low level VD2_L of the second driving signal VD2 is -2V; when the high level CMD2_H of the second control signal CMD2 is +5V, the high level VD2_H of the second driving signal VD2 is +7V, that is, the spatial light modulator driving device of the present invention outputs the second control signal CMD2 of 0~+5V through the level conversion unit 30 through the first control signal CMD1 output by the main control unit, and generates the second driving signal VD2 of -2V~+7V in combination with the signal conversion unit 20, the signal modulation unit 40 and the signal driving unit 50 to drive the LCoS spatial light modulation unit 70, and outputs the third pixel level signal VP3 of +5V as the reference level of the LCoS spatial light modulation unit 70. The LCoS spatial light modulation unit 70 realizes light modulation of the spatial light modulator by receiving the second driving signal and the third pixel level signal VP3.

[0064] Embodiment 2: A spatial light modulator driving method comprises the following steps:

[0065] S1. The main control unit dynamically sets and controls the output of the first digital signal SPI1, the second digital signal SPI2 and the first control signal CMD1 through a program.

[0066] S2. The signal conversion unit 20 receives the first digital signal SPI1 and the second digital signal SPI2, implements the configuration of the signal conversion unit 20, and generates a first pixel level signal VP1 of +5V and a first black field level signal VB1 of +2V through analog-to-digital conversion.

[0067] S3. The level conversion unit 30 receives the first control signal CMD1 and generates the second control signal CMD2 through level conversion. That is, the first control signal CMD1 is converted from low level CMD1_L=0V and high level CMD_H=+1.8V to the second control signal CMD2 with low level CMD2_L=0V and high level CMD2_H=+5V, and the frequency is 10Khz.

[0068] S4, the first driving unit 50 receives the first pixel level signal VP1 and the first black field level signal VB1, and outputs a second pixel level signal VP2, where the second pixel level signal VP2 is the difference between the first pixel level signal VP1 and the first black field level signal VB1, that is, VP2=VP1-VB1=+3V;

[0069] S5, the signal modulation unit 40 receives the first pixel level signal VP1, the second pixel level signal VP2 and the first black field level signal VB1, and outputs the first modulation signal VT1 and the second modulation signal VT2 under the action of the second control signal CMD2; if the second control signal CMD2 is at a high level CMD2_H=+5V, the high level VT1_H of the first modulation signal VT1 and the high level VT2_H of the second modulation signal VT2 are output. If it is at a low level CMD2_L=0V, the low level VT1_L of the first modulation signal VT1 and the low level VT2_L of the second modulation signal VT2 are output. The level values ​​of the first and second modulation signals VT2 corresponding to the high and low levels of the second control signal CMD2 are different. That is, the level of the first modulation signal VT1 and the level of the second modulation signal VT2 are determined by the high and low levels of the second control signal CMD2, and change with the level flip of the second control signal CMD2. For example: VT1_H=VP2= VP1-VB1=+3V, VT2_H=VP1=+5V, VT1_L=VB1=+2V, VT2_L=0V.

[0070] S6. The second driving unit 502 receives the first modulation signal VT1 and the second modulation signal VT2, and outputs the first driving signal VD1 according to the difference in the level values ​​of the first modulation signal VT1 and the second modulation signal VT2. The level of the first driving signal VD1 is the difference between twice the second modulation signal VT2 and the first modulation signal VT1VT1, that is, VD1=2VT2-VT1. The first driving signal VD1 is a PWM signal, which has the same phase as the second control signal CMD2. The level amplitude of the first driving signal is adjusted in real time according to the level flip of the second control signal.

[0071] For example, if the second control signal CMD2 is at a high level of 5V, the high level of the first drive signal VD1 is +7V, that is, VD1_H=2VT2_H-VT1_H=VP1+VB1=+7V; if the second control signal CMD2 is at a low level of 0V, the low level of the first drive signal VD1 is -2V, that is, VD1_L=2VT2_L-VT1_L=-VB1=-2V.

[0072] The first drive signal VD1 adjusts the level of the first drive signal in real time following the flipping of the second control signal CMD2. The second control signal CMD2 is a 0-+5V PWM square wave signal, and the first drive signal VD1 is a -2V-+7V PWM square wave signal, both with a frequency of 10Khz.

[0073] S7. The third driving unit 503 receives the first driving signal VD1 and outputs the second driving signal VD2. The second driving signal VD2 has the same phase and level amplitude as the first driving signal VD1, VD2_H=+7V, VD2_L=-2V, and the second driving signal VD2 is a PWM square wave signal of -2V-+7V, with a frequency of 10Khz. The driving capability of the second driving signal VD2 is better than that of the first driving signal VD1.

[0074] S8, the fourth driving unit 504 receives the first pixel level signal VP1 and generates a third pixel level signal VP3. The third pixel level signal VP3 has the same level as the first pixel level signal VP1 and has a better driving capability than the first pixel level signal VP1, and the signal level amplitude VP3=VP1=+5V;

[0075] S9. The LCoS spatial light modulation unit 70 receives the second driving signal VD2 and the fourth pixel level signal VP4 to modulate the spatial light.

[0076] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. A spatial light modulator driving device, characterized in that: It includes a main control unit, a signal conversion unit, a level conversion unit, a signal modulation unit, a signal driving unit, a power supply unit and an LCoS spatial light modulation unit; Wherein, the main control unit is used to convert and adjust the signal output by the signal conversion unit; the main control unit outputs a first digital signal, a second digital signal and a first control signal; The signal conversion unit is used for the reference input of the signal modulation unit; the signal conversion unit receives the first digital signal and the second digital signal, and generates a first pixel level signal and a first black field level signal; The level conversion unit is used to control the driving signal of the LCoS output by the signal modulation unit; the level conversion unit receives the first control signal output by the main control unit and converts the level into the second control signal. The signal modulation unit receives the first pixel level signal and the first black field level signal, and under the control of the second control signal, realizes the output of the positive and negative level digital driving signal, and the signal modulation unit outputs the first modulation signal and the second modulation signal; The signal driving unit is used to increase the driving capability of the signal and output a third pixel level signal and a second driving signal; The power supply unit is used to generate different voltages and provide them to each functional unit to ensure the normal and stable operation of the unit; The LCoS spatial light modulation unit receives the third pixel level signal and the second driving signal to modulate the spatial light.

2. The spatial light modulator driving device according to claim 1, characterized in that: The signal driving unit comprises a first driving unit, a second driving unit, a third driving unit and a fourth driving unit; the first driving unit, the second driving unit, the third driving unit and the fourth driving unit each comprise a positive phase input terminal, a negative phase input terminal, positive and negative power supply input terminals and an output terminal; The positive phase input terminal of the first driving unit is connected to the port of the signal conversion unit outputting the first pixel level signal, the negative phase input terminal is connected to the port of the signal conversion unit outputting the first black field level signal, and the output terminal outputs the second pixel level signal and is connected to the signal modulation unit; The positive phase input terminal of the second driving unit is connected to the port of the signal modulation unit outputting the first modulation signal, the negative phase input terminal is connected to the port of the signal modulation unit outputting the second modulation signal, outputs the first driving signal, and is connected to the positive phase input terminal of the third driving unit; The output end of the third driving unit outputs a second driving signal and is connected to the LCoS spatial light modulation unit; The non-phase input terminal of the fourth driving unit is connected to the port of the signal conversion unit outputting the first pixel level signal, and the output terminal outputs the third pixel level signal and is connected to the LCoS spatial light modulation unit.

3. The spatial light modulator driving device according to claim 2, characterized in that: The signal modulation unit comprises a signal control input terminal, a first data input terminal, a second data input terminal, a third data input terminal, a first data output terminal and a second data output terminal; Among them, the signal control input end is connected to the level conversion unit, the first data input end is connected to the output end of the first driving unit, the second data input end is connected to the port of the signal conversion unit outputting the first pixel level signal, the third data input end is connected to the port of the signal conversion unit outputting the first black field level signal, the first data output end outputs the first modulation signal and is connected to the positive phase input end of the second driving unit, and the second data output end outputs the second modulation signal and is connected to the negative phase input end of the second driving unit.

4. A spatial light modulator driving device according to claim 2 or 3, characterized in that: The main control unit includes an FPCA chip, and the signal conversion unit includes a first DAC digital-to-analog converter and a second DAC digital-to-analog converter; the FPCA chip is connected to the first DAC digital-to-analog converter and the second DAC digital-to-analog converter via an SPI serial port, and the level conversion unit is connected via the SPI serial port FPCA chip, the signal modulation unit includes a multi-way signal selector, and the signal driving unit includes a first operational amplifier, a second operational amplifier, a third operational amplifier, and a fourth operational amplifier; the first DAC digital-to-analog converter is connected to the positive phase input terminal of the first operational amplifier via a resistor, and the first DAC digital-to-analog converter is connected to the IN3 pin of the multi-way signal selector; the second DAC digital-to-analog converter is connected to the negative phase input terminal of the first operational amplifier via a resistor, and the second DAC digital-to-analog converter is connected to the IN2 pin of the multi-way signal selector; the positive phase input terminal of the first operational amplifier is connected to the output terminal of the first operational amplifier, and the negative phase input terminal of the first operational amplifier is connected via The resistor is grounded, the output end of the first operational amplifier is connected to the IN1 pin of the multiplexer; the level conversion unit is connected to the CTL pin of the multiplexer; the IN4 pin of the multiplexer is grounded; the OUT2 pin of the multiplexer is connected to the positive phase input end of the second operational amplifier, the OUT1 pin of the multiplexer is connected to the negative phase input end of the second operational amplifier through a resistor, the negative phase input end of the second operational amplifier is connected to the output end of the second operational amplifier through a resistor, and the output end of the second operational amplifier is connected to the positive phase input end of the third operational amplifier; the negative phase input end of the third operational amplifier is connected to the output end of the third operational amplifier through a resistor, and the output end of the third operational amplifier is connected to the LCoS spatial light modulation unit; the second DAC digital-to-analog converter is connected to the positive phase input end of the fourth operational amplifier, the negative phase input end of the fourth operational amplifier is connected to the output end of the fourth operational amplifier through a resistor, and the output end of the fourth operational amplifier is connected to the LCoS spatial light modulation unit.

5. The spatial light modulator driving device according to claim 4, characterized in that: The amplitude of the first pixel level signal is greater than the amplitude of the first black field level signal.

6. The spatial light modulator driving device according to claim 5, characterized in that: The first control signal and the second control signal have the same frequency and the same low level amplitude; the high level of the first control signal is a first amplitude and is determined by the main control unit; the high level of the second control signal is a second amplitude and is determined by the level conversion unit through the interface level of the signal modulation unit.

7. The spatial light modulator driving device according to claim 4, characterized in that: The first modulation signal and the second modulation signal are determined by the high and low levels of the second control signal; When the second control signal is at a high level, the first modulation signal is the difference between the first pixel level signal and the first black field level signal, and the second modulation signal is the first pixel level signal; When the second control signal is at a low level, the first modulation signal is a first black field level signal, and the second modulation signal is 0V.

8. The spatial light modulator driving device according to claim 4, characterized in that: The first drive signal and the second drive signal are set as PWM square wave signals, the frequencies of the first drive signal and the second drive signal are the same as the frequency of the first control signal, the low level of the second drive signal is the negative value of the first black field level signal, and the high level of the second drive signal is the sum of the first pixel level signal and the first black field level signal.

9. The spatial light modulator driving device according to claim 4, characterized in that: The third pixel level signal is a DC level signal, and the third pixel level signal has the same amplitude as the first pixel level signal.

10. A spatial light modulator driving method, characterized in that: The following steps are involved: S1, the main control unit dynamically sets and controls the output of the first digital signal, the second digital signal and the first control signal through a program; S2, a signal conversion unit receives the first digital signal and the second digital signal and generates a first pixel level signal and a first black field level signal respectively through analog-to-digital conversion; S3, the level conversion unit receives the first control signal and generates a second control signal through level conversion; S4, the first driving unit receives the first pixel level signal and the first black field level signal, and outputs a second pixel level signal, where the second pixel level signal is a difference between the first pixel level signal and the first black field level signal; S5, the signal modulation unit receives the first pixel level signal, the second pixel level signal and the first black field level signal, and outputs the first modulation signal and the second modulation signal under the action of the second control signal; if the second control signal is at a high level, the high level of the first modulation signal and the high level of the second modulation signal are output; if the second control signal is at a low level, the low level of the first modulation signal and the low level of the second modulation signal are output; S6, the second driving unit receives the first modulation signal and the second modulation signal, and outputs the first driving signal according to the difference between the level values ​​of the first modulation signal and the second modulation signal, the level of the first driving signal is the difference between twice the second modulation signal and the first modulation signal, the first driving signal is a PWM signal, and has the same phase as the second control signal, and the level amplitude of the first driving signal is adjusted in real time according to the level flipping of the second control signal; that is, the first driving signal adjusts the level of the first driving signal in real time following the flipping of the second control signal; S7, the third driving unit receives the first driving signal and outputs a second driving signal, the second driving signal has the same phase and level amplitude as the first driving signal, and the driving capability is better than the first driving signal; S8, the fourth driving unit receives the first pixel level signal and generates a third pixel level signal, the third pixel level signal has the same level as the first pixel level signal and has a better driving capability than the first pixel level signal; S9. The LCoS spatial light modulation unit receives the second driving signal and the third pixel level signal to modulate the spatial light.

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