Compensation Device and System for LCoS Chip

Abstract

The present application provides a compensation device and system for an LCoS chip, relating to the field of display technologies. The device includes: a wavefront measurement module, a processing module, and a micro-control module; the wavefront measurement module is configured to measure an interference pattern generated by the LCoS chip to be measured, and measure interference fringes generated when different test grayscale patterns are loaded on the LCoS chip; the processing module is configured to process the interference pattern to obtain initial surface shape data of the LCoS chip, and process the interference fringes to generate a grayscale-phase response curve of the LCoS chip; the micro-control module is configured to obtain a voltage-phase compensation curve of the LCoS chip according to the initial surface shape data and the grayscale-phase response curve, so as to compensate the phase of each pixel point on the LCoS chip in the LCoS device to be compensated based on the voltage-phase compensation curve, ensuring the accuracy of the compensation result and improving the phase modulation uniformity of the LCoS chip.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and in particular, to a compensation device and system for an LCoS chip. Background Art

[0002] A liquid crystal on silicon (LCoS) microdisplay chip is an optical device based on reflective liquid crystal display technology and is widely used in fields such as projection display, spatial light modulator (SLM), and optical communication. Among them, the LCoS microdisplay chip controls the direction of liquid crystal molecules by applying a voltage to pixel electrodes, thereby changing the phase or polarization state of incident light.

[0003] However, in practical applications, due to the influence of material properties, manufacturing processes, and environmental factors, the surface of the LCoS chip is not flat enough or has a certain warpage, thus affecting its performance. Therefore, there is an urgent need to propose a device for surface shape measurement and compensation for an LCoS chip. Summary of the Invention

[0004] The purpose of the present invention is to provide a compensation device and system for an LCoS chip to solve the technical problems existing in the prior art in view of the deficiencies in the above-mentioned prior art.

[0005] To achieve the above purpose, the technical solutions adopted in the embodiments of the present application are as follows:

[0006] In a first aspect, an embodiment of the present application provides a compensation and correction device for an LCoS chip, including: a wavefront measurement module, a processing module, and a micro control module; an output end of the wavefront measurement module is connected to an input end of the processing module, and an output end of the processing module is connected to an input end of the micro control module;

[0007] The wavefront measurement module is configured to reflect an input light source array according to a preset reflection optical path, measure an interference pattern generated by a to-be-tested LCoS chip, and measure interference fringes generated when different test gray scale patterns are loaded on the LCoS chip, and transmit the interference pattern and the interference fringes corresponding to each test gray scale pattern to the processing module;

[0008] The processing module is configured to process the interference pattern to obtain initial surface shape data of the LCoS chip, process the interference fringes to generate a gray scale-phase response curve of the LCoS chip, and transmit the initial surface shape data and the gray scale-phase response curve to the micro control module;

[0009] The micro control module is configured to obtain a voltage-phase compensation curve of the LCoS chip according to the initial surface shape data and the gray-scale phase response curve, so as to compensate the phases of the pixel points on the LCoS chip in the LCoS device to be compensated based on the voltage-phase compensation curve of the LCoS chip.

[0010] Optionally, the wavefront measurement module includes: a polarization conversion unit, a first double telecentric lens unit, a depolarizing beam splitter prism, a mirror, a second double telecentric lens unit, a detection unit, and a mounting base;

[0011] The mounting base is configured to fixedly mount the LCoS chip to be measured;

[0012] The polarization conversion unit is configured to convert the input light source array into P light and reflect the P light to the first double telecentric lens unit;

[0013] The first double telecentric lens unit is configured to collimate and expand the P light, so that the expanded reflected light completely covers the display area of the LCoS chip;

[0014] The depolarizing beam splitter prism is configured to split the expanded reflected light into a first beam of P light and a second beam of P light, and the first beam of P light is reflected to the mirror to form a reference light, and the second beam of P light is reflected to the LCoS chip to form a reflected light;

[0015] The second double telecentric lens unit is configured to reduce the reference light and the reflected light, so that the reduced interference spot completely enters the detection unit;

[0016] The detection unit is configured to collect the interference pattern formed by the reference light and the reflected light and transmit the interference pattern to the processing module.

[0017] Optionally, the detection unit is further configured to:

[0018] Collect the interference fringes formed by the reference light and the reflected light after the LCoS chip displays the first test gray-scale pattern, and transmit the interference fringes corresponding to the first test gray-scale pattern to the processing module.

[0019] Optionally, the first double telecentric lens unit includes: a first lens and a second lens, and the focal length of the first lens is less than the focal length of the second lens.

[0020] Optionally, the second double telecentric lens unit includes: a third lens and a fourth lens, and the focal length of the third lens is greater than the focal length of the fourth lens.

[0021] Optionally, the processing of the interference pattern to obtain the initial surface profile data of the LCoS chip includes:

[0022] Performing a transformation process on the interference pattern to obtain the phase information of the LCoS chip;

[0023] Performing phase unwrapping on the phase information of the LCoS chip to obtain the initial surface profile data of the LCoS chip.

[0024] Optionally, the processing of the interference fringes to generate the gray-scale - phase response curve of the LCoS chip includes:

[0025] Determining the phase value corresponding to each test gray-scale image according to the interference fringes corresponding to each test gray-scale image;

[0026] Performing a fitting process on each test gray-scale image and the phase value corresponding to each test gray-scale image to obtain the gray-scale - phase response curve of the LCoS chip.

[0027] Optionally, the test gray-scale images loaded by the LCoS chip include: an upper half region and a lower half region, where the gray-scale value of the upper half region is any gray-scale value from 0 to 255, and the gray-scale value of the lower half region is 0;

[0028] The determining the phase value corresponding to each test gray-scale image according to the interference fringes corresponding to each test gray-scale image includes:

[0029] Obtaining a first interference fringe in the upper half region and a second interference fringe in the lower half region of the interference fringes corresponding to the test gray-scale image;

[0030] Determining the offset of the interference fringes according to the first interference fringe and the second interference fringe;

[0031] Obtaining the period of the interference fringes, and determining the phase value corresponding to the test gray-scale image according to the period of the interference fringes and the offset of the interference fringes.

[0032] Optionally, the obtaining the voltage - phase compensation curve of the LCoS chip according to the initial surface profile data and the gray-scale - phase response curve includes:

[0033] Obtaining the relationship between the gray-scale and voltage of the pre-constructed LCoS chip;

[0034] Determining the voltage - phase response curve of the LCoS chip according to the relationship between the gray-scale and voltage of the LCoS chip and the gray-scale - phase response curve of the LCoS chip;

[0035] Determine the voltage-phase compensation curve of the LCoS chip according to the initial surface profile data and the voltage-phase response curve.

[0036] In a second aspect, an embodiment of the present application further provides a compensation system for an LCoS chip. The system includes: the compensation device provided in the first aspect above and the LCoS device to be compensated; wherein, the LCoS device to be compensated includes: a driving module and an LCoS chip module;

[0037] A first input end of the driving module is connected to an output end of a micro-control module in the compensation device of the LCoS chip. A second input end of the driving module is used to obtain video source data to be displayed. An output end of the driving module is connected to an input end of the LCoS chip module;

[0038] The driving module is configured to parse and process the obtained video source data to obtain voltage signals of each pixel point on each frame of the image to be displayed, and obtain the voltage-phase compensation curve of the LCoS chip module output by the micro-control module. According to the voltage signals of each pixel point and the voltage-phase compensation curve, obtain the phase compensation amount of each pixel point, and send the phase compensation amount of each pixel point to the LCoS chip module;

[0039] The LCoS chip module performs compensation according to the phase compensation amount of each pixel point to obtain the compensated phase of each pixel point, and performs display based on the compensated phase of each pixel point.

[0040] The beneficial effects of the present application are:

[0041] An embodiment of the present application provides a compensation device and system for an LCoS chip, including: a wavefront measurement module, a processing module, and a micro control module; the output end of the wavefront measurement module is connected to the input end of the processing module, and the output end of the processing module is connected to the input end of the micro control module; the wavefront measurement module is configured to reflect the input light source array according to a preset reflection optical path, measure the interference pattern generated by the LCoS chip to be measured, and measure the interference fringes generated when different test grayscale patterns are loaded on the LCoS chip, and transmit the interference pattern and the interference fringes corresponding to each test grayscale pattern to the processing module; the processing module is configured to process the interference pattern to obtain the initial surface shape data of the LCoS chip, process the interference fringes to generate a grayscale-phase response curve of the LCoS chip, and transmit the initial surface shape data and the grayscale-phase response curve to the micro control module; the micro control module is configured to obtain a voltage-phase compensation curve of the LCoS chip according to the initial surface shape data and the grayscale-phase response curve, so as to compensate the phase of each pixel point on the LCoS chip in the LCoS device to be compensated based on the voltage-phase compensation curve of the LCoS chip. In this solution, in the measurement stage, in order to improve the measurement accuracy of the wavefront reflection result of the LCoS chip, it is proposed that the wavefront measurement module measure the interference fringes when each test grayscale pattern is displayed on the LCoS chip and the interference pattern when the grayscale pattern is not displayed (LCoS is not powered on); then, the processing module processes the interference fringes and the interference pattern when each test grayscale pattern is displayed respectively to obtain the initial surface shape data and the grayscale-phase response curve of the LCoS chip; finally, the micro control module calculates a voltage-phase compensation curve of the LCoS chip according to the initial surface shape data and the grayscale-phase response curve of the LCoS chip, so as to compensate the phase of each pixel point on the LCoS chip in the LCoS device to be compensated based on the voltage-phase compensation curve of the LCoS chip, that is, the phase information of each pixel point in the LCoS chip can be measured and compensated, which can ensure the accuracy of the compensation result, thereby improving the display effect of the LCoS chip. Description of the Drawings

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0043] Figure 1 It is a schematic structural diagram of a compensation device for an LCoS chip provided by an embodiment of the present application;

[0044] Figure 2Schematic diagram of the initial surface profile data of the LCoS chip to be measured provided by the embodiments of the present application;

[0045] Figure 3 Schematic diagram of the structure of the wavefront measurement module in a compensation device for an LCoS chip provided by the embodiments of the present application;

[0046] Figure 4 Schematic diagram of the processing flow of the processing module in a compensation device for an LCoS chip provided by the embodiments of the present application;

[0047] Figure 5 Schematic diagram of the processing flow of the processing module in another compensation device for an LCoS chip provided by the embodiments of the present application;

[0048] Figure 6(a) is a test grayscale image provided by the embodiments of the present application;

[0049] Figure 6(b) is a schematic diagram of interference fringes provided by the embodiments of the present application;

[0050] Figure 7 Schematic diagram of the processing flow of the processing module in yet another compensation device for an LCoS chip provided by the embodiments of the present application;

[0051] Figure 8 Schematic diagram of the processing flow of the micro control module in a compensation device for an LCoS chip provided by the embodiments of the present application;

[0052] Figure 9 Schematic diagram of the structure of a compensation system for an LCoS chip provided by the embodiments of the present application.

[0053] Icon: 100 - compensation device; 1 - wavefront measurement module; 2 - processing module; 3 - micro control module; 11 - polarization conversion unit; 12 - first double telecentric lens unit; 13 - depolarizing beam splitter prism; 14 - mirror; 15 - second double telecentric lens unit; 16 - detection unit; 17 - mounting base; 200 - LCoS device to be compensated; 201 - driving module; 202 - LCoS chip module. Detailed implementation manners

[0054] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. It should be understood that the accompanying drawings in this application are only for the purposes of illustration and description, and are not used to limit the protection scope of this application. In addition, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate the operations implemented according to some embodiments of this application. It should be understood that the operations in the flowchart may not be implemented in sequence, and steps without a logical context relationship may be reversed or implemented simultaneously. In addition, those skilled in the art may add one or more other operations to the flowchart or remove one or more operations from the flowchart under the guidance of the content of this application.

[0055] In addition, the described embodiments are only some embodiments of this application, rather than all embodiments. The components of the embodiments of this application usually described and illustrated in the accompanying drawings here may be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of this application claimed, but only represents the selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative efforts belong to the scope of protection of this application.

[0056] It should be noted that the term "including" will be used in the embodiments of this application to indicate the existence of the features stated hereinafter, but does not exclude the addition of other features.

[0057] The following will detail the structure of the compensation device for the LCoS chip of this application through multiple embodiments.

[0058] Figure 1 It is a schematic structural diagram of a compensation device for an LCoS chip provided for the embodiments of this application; as Figure 1 shown, the compensation device 100 of the LCoS chip includes: a wavefront measurement module 1, a processing module 2, and a micro-control module 3. Among them, the output end of the wavefront measurement module 1 is connected to the input end of the processing module 2, and the output end of the processing module 2 is connected to the input end of the micro-control module 3.

[0059] Exemplarily, both the processing module 2 and the micro-control module 3 may be terminal devices with data processing functions.

[0060] The wavefront measurement module 1 is used to reflect the input light source array according to a preset reflection optical path, measure the interference pattern generated by the LCoS chip to be measured, and measure the interference fringes generated when the LCoS chip displays different test gray-scale patterns, and transmit the interference pattern and the interference fringes corresponding to each test gray-scale pattern to the processing module 2. Exemplarily, the light source array can be in the visible light band or the infrared band, etc.

[0061] Optionally, the wavefront measurement module 1 is composed of multiple optical elements. The light source array is input into the wavefront measurement module 1, and the wavefront measurement module 1 measures the reflected wavefront information when the LCoS chip displays each gray-scale pattern. For example, the wavefront information can include modulation efficiency, phase consistency, etc.

[0062] In this embodiment, mainly the wavefront measurement module 1 measures the interference pattern when the LCoS chip has not displayed a gray-scale pattern (LCoS is not powered on), and the interference fringes generated when different test gray-scale patterns are displayed on the LCoS chip, and sends the interference pattern and the interference fringes corresponding to each test gray-scale pattern to the processing module, and the processing module processes the interference pattern and the interference fringes corresponding to each test gray-scale pattern.

[0063] Continue to refer to Figure 1 As shown, the processing module 2 is used to process the interference pattern to obtain the initial surface shape data of the LCoS chip, process the interference fringes to generate the gray-scale-phase response curve of the LCoS chip, and transmit the initial surface shape data and the gray-scale-phase response curve to the micro control module 3.

[0064] In this embodiment, since the interference pattern is generated when the LCoS chip does not display any gray-scale pattern. Therefore, the initial surface shape data of the LCoS chip can be obtained from the interference pattern of the LCoS chip. The initial surface shape data includes: the height values of each position point on the surface of the LCoS chip, the difference between the highest and the lowest points, and the mean square deviation of the surface shape data, with the unit of one measurement wavelength.

[0065] For example, referring to Figure 2 As shown, it is the initial surface shape data of the LCoS chip to be measured, and the flatness and roughness of the surface of the LCoS chip can also be determined from the initial surface shape data.

[0066] At the same time, since each interference fringe is generated when the LCoS chip displays different test gray-scale patterns, and the change of the interference fringe is related to the phase information of the LCoS chip. Therefore, the gray-scale-phase response curve of the LCoS chip can be calculated from the interference fringes corresponding to each test gray-scale pattern.

[0067] The micro-control module 3 is configured to obtain a voltage-phase compensation curve of the LCoS chip according to the initial surface profile data and the gray-scale phase response curve, so as to compensate the phases of the pixel points on the LCoS chip in the LCoS device to be compensated based on the voltage-phase compensation curve of the LCoS chip.

[0068] Exemplarily, the LCoS device to be compensated may be a projection display device, a spatial light modulator, etc. manufactured based on the LCoS device.

[0069] Specifically, the micro-control module 3 can determine the phase information of all pixel points on the surface of the LCoS chip according to the initial surface profile data of the LCoS chip; then, according to the phase information of all pixel points on the surface of the LCoS chip and the gray-scale phase response curve, a voltage-phase compensation curve of the LCoS chip is obtained, so that the phases of the pixel points on the LCoS chip in the LCoS device to be compensated can be compensated based on the voltage-phase compensation curve of the LCoS chip, ensuring the accuracy of the display result.

[0070] Therefore, when measuring the reflected wavefront information of the LCoS chip by the wavefront measurement module, the phase information of each pixel point in the LCoS chip is directly measured, so that the accuracy of the compensation result can be ensured.

[0071] In summary, the embodiment of the present application provides a compensation device for an LCoS chip, including: a wavefront measurement module, a processing module, and a micro-control module; the output end of the wavefront measurement module is connected to the input end of the processing module, and the output end of the processing module is connected to the input end of the micro-control module; the wavefront measurement module is configured to reflect the input light source array according to a preset reflection optical path, measure the interference pattern generated by the LCoS chip to be measured, and measure the interference fringes generated when the LCoS chip is loaded with different test grayscale images, and transmit the interference pattern and the interference fringes corresponding to each test grayscale image to the processing module; the processing module is configured to process the interference pattern to obtain the initial surface shape data of the LCoS chip, process the interference fringes to generate a grayscale-phase response curve of the LCoS chip, and transmit the initial surface shape data and the grayscale-phase response curve to the micro-control module; the micro-control module is configured to obtain a voltage-phase compensation curve of the LCoS chip according to the initial surface shape data and the grayscale-phase response curve, so as to compensate the phase of each pixel point on the LCoS chip in the LCoS device to be compensated based on the voltage-phase compensation curve of the LCoS chip. In this solution, in the measurement stage, in order to improve the measurement accuracy of the wavefront reflection result of the LCoS chip, it is proposed that the wavefront measurement module can measure the interference fringes when the LCoS chip displays each test grayscale image and the interference pattern when the grayscale image is not displayed (LCoS is not powered on); then, the processing module processes the interference fringes and the interference pattern when each test grayscale image is displayed respectively to obtain the initial surface shape data and the grayscale-phase response curve of the LCoS chip; finally, the micro-control module calculates a voltage-phase compensation curve of the LCoS chip according to the initial surface shape data and the grayscale-phase response curve of the LCoS chip, so as to compensate the phase of each pixel point on the LCoS chip in the LCoS device to be compensated based on the voltage-phase compensation curve of the LCoS chip, that is, the phase information of each pixel point in the LCoS chip can be measured and compensated, which can ensure the accuracy of the compensation result, thereby improving the display effect of the LCoS chip.

[0072] The structure of the wavefront measurement module will be specifically introduced through the following embodiments.

[0073] Optionally, refer to Figure 3 shown, which is a schematic structural diagram of the wavefront measurement module.

[0074] Among them, the wavefront measurement module 1 includes: a polarization conversion unit 11, a first double telecentric lens unit 12, a depolarizing beam splitter prism 13, a mirror 14, a second double telecentric lens unit 15, a detection unit 16, and a mounting base 17.

[0075] Among them, the mounting base 17 is used to fixedly mount the LCoS chip to be measured. Before starting the measurement, first mount the LCoS chip to the mounting base 17 and ensure that the incident light can completely cover the entire display area of the LCoS chip. Then, manually adjust the angle of the mounting base 17 so that the detection unit 16 can detect the interference pattern formed by the reference light and the reflected light of the LCoS chip.

[0076] The polarization conversion unit 11 is used to convert the input light source array into P light and reflect the P light to the first double telecentric lens unit 12.

[0077] In this embodiment, the polarization conversion unit 11 can achieve the conversion of all incident light into P light. Among them, continue to refer to Figure 3 As shown, the polarization conversion unit is composed of a quarter-wave plate, a polarizing beam splitter (PBS for short), and a mirror (MIRRO). The optical axis of the quarter-wave plate is at 45° to the liquid crystal alignment direction. Since the incident light is unpolarized light, after passing through the quarter-wave plate, neither the amplitude nor the phase changes.

[0078] The polarizing beam splitter (PBS) is an optical element that divides the incident light into two beams of light with mutually perpendicular polarization directions, that is, P light (parallel to the paper surface) and S light (perpendicular to the paper surface). In this solution, P light can directly pass through the polarizing beam splitter, and S light is reflected by the mirror surface of the polarizing beam splitter, then reflected by the mirror, and the polarization direction does not change. Then it is reflected by the polarizing beam splitter and passes through the quarter-wave plate again, and is reflected by the light source array and passes through the quarter-wave plate again. Passing through the quarter-wave plate twice causes the polarization direction to rotate 90°, changing from S light to P light, and finally all passing through the polarizing beam splitter. Thus, the purpose of converting all incident light into P light is achieved.

[0079] Continue to refer to Figure 3 As shown, the first double telecentric lens unit 12 is used to collimate and expand the P light so that the expanded reflected light completely covers the display area of the LCoS chip. Exemplarily, the first double telecentric lens unit 12 can be a collimating and expanding device.

[0080] The non-polarizing beam splitter 13 (NPBS for short) is used to divide the expanded reflected light into a first beam of P light and a second beam of P light, and the first beam of P light is reflected to the mirror 14 to form a reference light, and the second beam of P light is reflected to the LCoS chip to form a reflected light.

[0081] Among them, the splitting ratio of the depolarizing beam splitter prism 13 is independent of the polarization state of the incident light. It can split the incident light with any polarization state into two beams of light with a ratio close to 1:1, and the polarization state of the outgoing light is approximately the same as that of the incident light. Therefore, the expanded reflected light (i.e., the incident P light) can be split into two beams of P light by the depolarizing beam splitter prism 13. Among them, one beam of P light is reflected to the mirror 14 to form a reference light, and the other beam of P light is reflected by the LCoS chip to form a reflected light. The reference light and the reflected light reflected by the LCoS chip form an interference pattern at the position of the detection unit 16, which is also called a wrapped phase map.

[0082] The second double telecentric lens unit 15 is used to reduce the reference light and the reflected light so that the reduced interference spot can enter the detection unit 16 completely. Optionally, in order to enable the detection unit 16 to measure the complete interference spot, the size of the interference spot formed by the reference light and the reflected light can be reduced by the second double telecentric lens unit 15 so that it can completely enter the detection area in the detection unit 16 and then be completely collected.

[0083] The detection unit 16 is used to collect the interference pattern formed by the reference light and the reflected light and transmit the interference pattern to the processing module.

[0084] Exemplarily, the detection unit 16 is a high-resolution CCD industrial camera, which is used to collect the interference pattern formed by the reference light and the reflected light.

[0085] Among them, the LCoS chip is fixedly installed on the mounting base 17. The mounting base 17 has a certain rotation space. By rotating the mounting base 17, it is ensured that the reflected light of the LCoS chip and the reference light from the mirror can form an interference pattern, and the interference pattern is formed by the detection unit 16.

[0086] Optionally, the detection unit 16 is further used for:

[0087] Collecting the interference fringes formed by the reference light and the reflected light after the first test gray scale map is displayed on the LCoS chip, and transmitting the interference fringes corresponding to the first test gray scale map to the processing module.

[0088] It should be noted that in order to obtain the gray scale-phase response curve of the LCoS chip, different test gray scale maps can be loaded on the LCoS chip, and the detection unit 16 respectively collects the interference fringes formed by the reference light and the reflected light after different test gray scale maps are displayed on the LCoS chip. Then, the interference fringes corresponding to each test gray scale map are transmitted to the processing module.

[0089] Optionally, continue to refer to Figure 3As shown in the figure, the first double telecentric lens unit includes: a first lens len1 and a second lens len2. The focal length f1 of the first lens len1 is less than the focal length f2 of the second lens len2, that is, f3 > f4. Therefore, a collimating and beam expanding system can be formed by the first lens len1 and the second lens len2, and the size of the expanded light spot can at least completely cover the display area of the LCoS chip.

[0090] Optionally, continue to refer to Figure 3 As shown in the figure, the second double telecentric lens unit includes: a third lens len3 and a fourth lens len4. The focal length f3 of the third lens len3 is greater than the focal length f4 of the fourth lens len4, that is, f3 > f4. Therefore, the size of the interference light spot can be reduced by the third lens len3 and the fourth lens len4 so that it completely enters the field of view of the detection unit 16 and is then completely collected.

[0091] The following embodiments will specifically explain how to obtain the initial surface profile data and the gray-scale phase response curve of the LCoS chip.

[0092] Optionally, refer to Figure 4 As shown in the figure, the interference pattern is processed to obtain the initial surface profile data of the LCoS chip, including:

[0093] S401. Perform a transformation process on the interference pattern to obtain the phase information of the LCoS chip.

[0094] In a feasible manner, the Fourier Transform Profilometry (FTP) or the Phase Measuring Profilometry (PMP) can be used to obtain the phase information of the LCoS chip from the interference pattern. Specifically, the interference pattern can be Fourier-transformed, and the fundamental frequency component can be obtained from the result of the Fourier transform. Then, the inverse Fourier transform is performed on the fundamental frequency component to obtain the phase information of the LCoS chip.

[0095] S402. Perform phase unwrapping on the phase information of the LCoS chip to obtain the initial surface profile data of the LCoS chip.

[0096] Optionally, after obtaining the phase information of the LCoS chip, since the phase is calculated by the arctangent (atan2), it will be truncated between [-π, π] or [0, 2π]. Therefore, the phase information of the LCoS chip can be phase-unwrapped to obtain the initial surface profile data of the LCoS chip. Among them, the unwrapping algorithms usually include: path tracking method, minimum norm method, and deep learning-based methods, etc.

[0097] Optionally, refer toFigure 5 As shown, the interference fringes are processed to generate the gray scale-phase response curve of the LCoS chip, including:

[0098] S501. Determine the phase value corresponding to each test gray scale image according to the interference fringes corresponding to each test gray scale image.

[0099] S502. Perform fitting processing on each test gray scale image and the phase value corresponding to each test gray scale image to obtain the gray scale-phase response curve of the LCoS chip.

[0100] In this embodiment, the interference fringes corresponding to each test gray scale image can be processed to obtain the phase value corresponding to each test gray scale image, and fitting processing is performed on the gray scale value represented by each test gray scale image and the phase value corresponding to each test gray scale image to generate the gray scale-phase response curve of the LCoS chip.

[0101] Optionally, as shown in FIG. 6(a), the test gray scale images loaded by the LCoS chip include: an upper half region and a lower half region. The gray scale value of the upper half region is any gray scale from 0 to 255, and the gray scale value of the lower half region is 0. Therefore, the number of gray scale images displayed in the upper half region is 256, and the number of gray scale images displayed in the lower half region is 1. That is, during the entire measurement process, the interference fringes in the upper half region change with the change of the gray scale value of the test gray scale image, while the interference fringes in the lower half region remain unchanged.

[0102] Refer to Figure 7 As shown, the above step S501 includes:

[0103] S701. Obtain the first interference fringes in the upper half region and the second interference fringes in the lower half region of the interference fringes corresponding to the test gray scale image.

[0104] S702. Determine the offset of the interference fringes according to the first interference fringes and the second interference fringes.

[0105] S703. Obtain the period of the interference fringes, and determine the phase value corresponding to the test gray scale image according to the period of the interference fringes and the offset of the interference fringes.

[0106] It should be noted that as shown in FIG. 6(b), when the LCoS chip sequentially displays different test gray scale images, the upper half region in the interference fringes will move relative to the lower half region. When the movement amount reaches one interference fringe period, a phase modulation of 2π is generated.

[0107] Therefore, in this embodiment, the relative movement amount of the interference fringes can be calculated according to the first interference fringes in the upper half region and the second interference fringes in the lower half region. ; Then, obtain the period T of the interference fringes (which is the average value of the spacing between two adjacent bright fringes or dark fringes), and determine the displacement amount of the interference fringes The ratio to the period T, that is , and calculate the product result of the ratio and 2π, that is , and use this product result as the phase value corresponding to the test gray scale image.

[0108] Optionally, referring to Figure 8 as shown, according to the initial surface shape data and the gray scale-phase response curve, obtain the voltage-phase compensation curve of the LCoS chip, including:

[0109] S801. Obtain the relationship between the gray scale and voltage of the pre-constructed LCoS chip.

[0110] S802. According to the relationship between the gray scale and voltage of the LCoS chip and the gray scale-phase response curve of the LCoS chip, determine the voltage-phase response curve of the LCoS chip.

[0111] S803. According to the initial surface shape data and the voltage-phase response curve, determine the voltage-phase compensation curve on the LCoS chip.

[0112] In this embodiment, considering that there is a certain proportional relationship (generally a linear relationship) between the gray scale and voltage of the LCoS chip, that is, the relationship between the gray scale and voltage can be substituted into the corresponding relationship of the gray scale-phase response curve to obtain the voltage-phase response curve of the LCoS chip; then, the initial surface shape data of the LCoS chip can also be used as the phase surface data. Therefore, the voltage-phase compensation curve on the LCoS chip can be obtained according to the phase surface data and the voltage-phase response curve of the LCoS chip. Finally, in the phase compensation stage, after the driving module obtains the voltage signal of each pixel on the LCoS chip, the phase of each pixel can be compensated based on the voltage signal of each pixel on the LCoS chip and the voltage-phase compensation response curve.

[0113] Optionally, referring to Figure 9 as shown, the present application also provides a schematic structural diagram of a compensation system for an LCoS chip. The system includes: the compensation device 100 provided in the above embodiment and the LCoS device 200 to be compensated; the LCoS device 200 to be compensated includes: a driving module 201 and an LCoS chip module 202;

[0114] The driving module 201 is configured to parse and process the acquired video source data to obtain the voltage signals of each pixel point on each frame of image to be displayed, and acquire the voltage-phase compensation curve of the LCoS chip module output by the micro-control module, and obtain the phase compensation amount of each pixel point according to the voltage signals of each pixel point and the voltage-phase compensation curve, and send the phase compensation amount of each pixel point to the LCoS chip module.

[0115] The LCoS chip module 202 performs compensation according to the phase compensation amount of each pixel point to obtain the compensated phase of each pixel point, and performs display based on the compensated phase of each pixel point.

[0116] In this embodiment, the driving module 201 parses and processes the video source data input by the user to obtain the voltage signals of each pixel point on each frame of the video source data, and calculates the phase compensation amount of each pixel point based on the voltage signals of each pixel point and the voltage-phase compensation curve, and sends the phase compensation amount of each pixel point to the LCoS chip module 202; then, the LCoS chip module 202 performs phase compensation according to the phase compensation amount of each pixel point to obtain the compensated phase of each pixel point, and performs display based on the compensated phase of each pixel point. Therefore, the compensation system of the LCoS chip provided by this application can compensate the phase of each pixel point, improve the display effect of the LCoS chip module, and avoid the situation of display errors.

[0117] In several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be through some interfaces, and the indirect coupling or communication connection of the device or unit can be in electrical, mechanical or other forms.

[0118] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place, or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0119] In addition, the functional units in various embodiments of the present invention may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware, or in the form of a combination of hardware and software functional units.

[0120] The above-mentioned integrated units implemented in the form of software functional units may be stored in a computer-readable storage medium. The above-mentioned software functional units stored in a storage medium include several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor (English: processor) to execute some steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (English: Read-Only Memory, abbreviated as: ROM), random access memories (English: Random Access Memory, abbreviated as: RAM), magnetic disks, or optical discs that can store program codes.

Claims

1. A compensation device for an LCoS chip, characterized in that: include: Wavefront measurement module, processing module and micro-control module; The output end of the wavefront measurement module is connected to the input end of the processing module, and the output end of the processing module is connected to the input end of the microcontroller module; The wavefront measurement module is used to reflect the input light source array according to a preset reflection light path, measure the interference pattern generated by the LCoS chip to be tested, and measure the interference fringes generated when the LCoS chip is loaded with different test grayscale images, and transmit the interference pattern and the interference fringes corresponding to each test grayscale image to the processing module; The processing module is used to process the interference pattern to obtain the initial surface data of the LCoS chip, process the interference fringes to generate the grayscale-phase response curve of the LCoS chip, and transmit the initial surface data and the grayscale-phase response curve to the microcontroller module; The microcontroller module is used to obtain a voltage-phase compensation curve of the LCoS chip according to the initial surface data and the grayscale-phase response curve, so as to compensate the phase of each pixel on the LCoS chip in the compensated LCoS device based on the voltage-phase compensation curve of the LCoS chip; The step of processing the interference fringes to generate a grayscale-phase response curve of the LCoS chip includes: Determining the phase value corresponding to each of the test grayscale images according to the interference fringes corresponding to each of the test grayscale images; Performing fitting processing on each of the test grayscale images and the phase value corresponding to each of the test grayscale images to obtain a grayscale-phase response curve of the LCoS chip; The test grayscale image loaded by the LCoS chip includes: an upper half area and a lower half area, the grayscale value of the upper half area is any grayscale between 0 and 255, and the grayscale value of the lower half area is 0; Determining the phase value corresponding to each of the test grayscale images according to the interference fringes corresponding to each of the test grayscale images includes: Obtaining first interference fringes in an upper half area and second interference fringes in a lower half area of ​​the interference fringes corresponding to the test grayscale image; Determining an offset of the interference fringes according to the first interference fringes and the second interference fringes; The period of the interference fringes is obtained, and the phase value corresponding to the test grayscale image is determined according to the period of the interference fringes and the offset of the interference fringes.

2. The device according to claim 1, characterized in that The wavefront measurement module comprises: a polarization conversion unit, a first double telecentric lens unit, a depolarizing beam splitter prism, a reflector, a second double telecentric lens unit, a detection unit and a mounting base; The mounting base is used to fix and mount the LCoS chip to be tested; The polarization conversion unit is used to convert the input light source array into P light, and reflect the P light to the first double telecentric lens unit; The first double telecentric lens unit is used to collimate and expand the P light so that the reflected light after expansion completely covers the display area of ​​the LCoS chip; The depolarizing beam splitter is used to split the reflected light after beam expansion into a first beam P light and a second beam P light, wherein the first beam P light is reflected to the reflector to form a reference light, and the second beam P light is reflected to the LCoS chip to form a reflected light; The second double telecentric lens unit is used to reduce the reference light and the reflected light so that all the reduced interference light spots enter the detection unit; The detection unit is used to collect the interference pattern formed by the reference light and the reflected light, and transmit the interference pattern to the processing module.

3. The device according to claim 2, characterized in that The detection unit is further used for: The interference fringes formed by the reference light and the reflected light after being reflected when the LCoS chip displays the first test grayscale image are collected, and the interference fringes corresponding to the first test grayscale image are transmitted to the processing module.

4. The device according to claim 2, characterized in that The first double telecentric lens unit includes: a first lens and a second lens, and the focal length of the first lens is smaller than the focal length of the second lens.

5. The device according to claim 2, characterized in that The second double telecentric lens unit includes: a third lens and a fourth lens, and the focal length of the third lens is greater than the focal length of the fourth lens.

6. The device according to claim 1, characterized in that The step of processing the interference pattern to obtain initial surface data of the LCoS chip includes: Transforming the interference pattern to obtain phase information of the LCoS chip; Phase information of the LCoS chip is phase unwrapped to obtain initial surface data of the LCoS chip.

7. The device according to claim 1, characterized in that The step of obtaining a voltage-phase compensation curve of the LCoS chip according to the initial surface data and the grayscale-phase response curve comprises: Obtaining a pre-constructed grayscale-voltage relationship of the LCoS chip; Determine a voltage-phase response curve of the LCoS chip according to a relationship between the grayscale and voltage of the LCoS chip and a grayscale-phase response curve of the LCoS chip; A voltage-phase compensation curve of the LCoS chip is determined according to the initial surface shape data and the voltage-phase response curve.

8. A compensation system for an LCoS chip, characterized in that: The system comprises: the compensation device according to any one of claims 1 to 7 and a compensated LCoS device; wherein the compensated LCoS device comprises: a driving module and an LCoS chip module; The first input end of the driving module is connected to the output end of the microcontroller module in the compensation device of the LCoS chip, the second input end of the driving module is used to obtain the video source data to be displayed, and the output end of the driving module is connected to the input end of the LCoS chip module; The driving module is used to parse and process the acquired video source data to obtain the voltage signal of each pixel on each frame of the image to be displayed, and to obtain the voltage-phase compensation curve of the LCoS chip module output by the microcontroller module, and to obtain the phase compensation amount of each pixel according to the voltage signal of each pixel and the voltage-phase compensation curve, and to send the phase compensation amount of each pixel to the LCoS chip module; The LCoS chip module performs compensation according to the phase compensation amount of each pixel to obtain the compensated phase of each pixel, and performs display based on the compensated phase of each pixel.

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