A device and method of measurement

Abstract

This application provides a measurement apparatus and method capable of accurately measuring the phase of an LCOS in a communication band. The apparatus includes: a polarization conversion device, a first lens, a beam splitter, an objective lens, and a second lens. The polarization conversion device acquires an input coherent beam and converts the polarization direction of the coherent beam to the polarization direction of the LCOS under test, generating a first beam. The first lens transmits the first beam to the beam splitter. The beam splitter transmits the first beam to the objective lens and transmits the interference beam from the objective lens to the second lens. The objective lens transmits the first beam to the LCOS under test and transmits the interference beam from the LCOS under test to the beam splitter, wherein the interference beam is generated by the LCOS under test based on the first beam emitted from the objective lens. The second lens transmits the interference beam emitted from the beam splitter to a detector, so that the detector measures the phase of the LCOS under test based on the interference beam.

Description

Technical Field

[0001] This application relates to the field of optical communications, and more specifically, to a measuring apparatus and method. Background Technology

[0002] Liquid crystal on silicon (LCOS) is a reflective spatial light modulator based on a silicon backplane. LCOS combines liquid crystal technology with CMOS technology, with optical phase modulation as its core, and is widely used in optical communication, display, and other fields. Due to its excellent passband tuning flexibility, optical network hardware compatibility, and beam deflection stability, LCOS is becoming increasingly common in wavelength selective switches (WSS) and is developing towards higher resolution and higher modulation depth.

[0003] However, high-resolution, high-modulation-depth LCOS in communication bands suffers from significant edge field effects, which reduce far-field diffraction efficiency and introduce non-ideal orders, leading to problems such as insertion loss, crosstalk, and polarization in WSS. Therefore, accurately characterizing the phase profile under the influence of edge field effects to optimize LCOS performance has become an urgent problem to be solved. Summary of the Invention

[0004] This application provides a measurement apparatus and method capable of accurately measuring the LCOS phase in a communication band.

[0005] In a first aspect, embodiments of this application provide a measurement apparatus applicable to a silicon-based liquid crystal (LCOS) under test. The apparatus includes: a polarization conversion device, a first lens, a beam splitter, an objective lens, and a second lens. The polarization conversion device acquires an input coherent light beam and converts the polarization direction of the coherent beam to the polarization direction of the LCOS under test, generating a first light beam. The first lens transmits the first light beam to the beam splitter. The beam splitter transmits the first light beam emitted from the first lens to the objective lens and transmits an interference beam from the objective lens to the second lens. The objective lens transmits the first light beam emitted from the beam splitter to the LCOS under test and transmits an interference beam from the LCOS under test to the beam splitter, wherein the interference beam is generated by the LCOS under test based on the first light beam emitted from the objective lens. The second lens transmits the interference beam emitted from the beam splitter to a detector, so that the detector measures the phase of the LCOS under test based on the interference beam.

[0006] For example, the polarization conversion device can be a linear polarizer. The detector can be a charge-coupled device (CCD) image sensor or a complementary metal-oxide-semiconductor (CMOS) image sensor, etc.

[0007] In one possible implementation, the measuring apparatus provided in this application further includes a laser and the detector. The laser is used to generate the coherent beam.

[0008] It should be noted that the first lens can focus the light beam onto the back focal plane of the objective lens after passing through the first lens, so that the light beam emitted from the objective lens is incident parallel to the LCOS under test. At this time, the width of the light beam is very narrow, and the entire light beam can only illuminate a few dozen pixels. Therefore, with this device, the phase profile of the LCOS can be precisely measured at a rate of a few dozen pixels.

[0009] Furthermore, the measuring device provided in this application is designed based on the single-arm interference principle, which has a simple structure and improves the stability of the measuring device.

[0010] In conjunction with the first aspect, in some implementations of the first aspect, the coherent beam is a laser beam with a visible light wavelength, and the operating wavelength of the LCOS under test is a communication band wavelength.

[0011] Typically, LCOS (Liquid Crystal Optical System) detectors operating in the communication band are coated with an anti-reflection film. This film increases the transmittance of light at communication band wavelengths while reducing the transmittance of light at visible band wavelengths. Therefore, using a coherent visible light beam can easily induce interference between transmitted and reflected visible light on the LCOS surface. This interference beam then passes through the objective lens, beam splitter, and second lens before reaching the detector. Using a visible light beam to measure the phase of the LCOS overcomes the diffraction-limited resolution limitations of measurements using communication band beams, achieving sub-pixel-level phase measurement and improving measurement accuracy.

[0012] In conjunction with the first aspect, in some implementations of the first aspect, the objective lens is a microscope objective lens. Based on the microscope objective lens, pixel-level phase measurement can be achieved, thereby improving the accuracy of the measurement.

[0013] In conjunction with the first aspect, in some implementations of the first aspect, the distance between the objective lens and the first lens is greater than the focal length of the first lens.

[0014] For example, the objective lens should be located behind the focal plane of the first lens. In one possible implementation, the focal plane of the first lens coincides with the rear focal plane of the objective lens.

[0015] It should be understood that in the measuring device provided in this application, the distance between the LCOS to be measured and the objective lens should meet the working distance of the objective lens.

[0016] In conjunction with the first aspect, in some implementations of the first aspect, the beam-splitting element is a beam splitter or an optical circulator.

[0017] Secondly, embodiments of this application provide a measurement method, which can be executed by a computing device (or processing device) connected to a detector or by a component (such as a chip or chip system) within the computing device (or processing device). The method includes: acquiring N interference patterns, wherein the N interference patterns correspond to N phase maps loaded on a silicon-based liquid crystal LCOS under test; generating a correspondence between the interference intensity and phase of each pixel of the detector based on the N interference patterns; acquiring the interference pattern of the phase map to be measured; and determining the phase profile of the LCOS under test loaded with the phase map to be measured based on the correspondence between the interference intensity and phase of each pixel of the detector, wherein N is an integer greater than 1.

[0018] Based on the above scheme, this application utilizes the phase modulation characteristics of LCOS itself for phase calibration, avoiding the introduction of a precision stepping platform, reducing measurement costs, and improving the stability and reliability of the measurement.

[0019] In conjunction with the second aspect, in some implementations of the second aspect, the method further includes: generating a phase-to-grayscale correspondence for the visible light band based on the correspondence between the interference intensity and phase of each pixel of the detector; converting the phase-to-grayscale correspondence for the visible light band into a phase-to-grayscale correspondence for the communication band. Determining the phase profile of the LCOS under test loaded with the phase map under test based on the correspondence between the interference intensity and phase of each pixel of the detector includes: determining the phase profile of the LCOS under test loaded with the phase map under test based on the phase-to-grayscale correspondence for the communication band.

[0020] Based on this scheme, the measurement method provided in this application can convert the phase-to-grayscale correspondence of the visible light band into the phase-to-grayscale correspondence of the communication band, thus enabling measurement of the communication band and realizing multi-band measurement.

[0021] In conjunction with the second aspect, in some implementations of the second aspect, the N interference patterns correspond to N gray levels and N phases.

[0022] In conjunction with the second aspect, in some implementations of the second aspect, acquiring the N interference patterns includes: acquiring the N interference patterns through a coherent beam in the visible light band.

[0023] In conjunction with the second aspect, in some implementations of the second aspect, the operating wavelength of the LCOS under test is a communication band wavelength.

[0024] Thirdly, embodiments of this application provide a computer-readable storage medium. The computer-readable storage medium is used to store a computer program that, when executed on a measuring device including one or more processors, causes the measuring device to perform the methods described in the second aspect or any possible implementation thereof.

[0025] Fourthly, embodiments of this application provide a computer program product. The computer program product includes a computer program that, when run, causes a computer to perform the method described in the second aspect or any possible implementation thereof.

[0026] Fifthly, embodiments of this application provide a chip. The chip is connected to a memory and is used to read and execute program code stored in the memory to implement the method in the second aspect or any possible implementation thereof.

[0027] The beneficial effects of the third to fifth aspects mentioned above can be found in the description of the beneficial effects in the second aspect, and will not be repeated here. Attached Figure Description

[0028] Figure 1 This is a schematic diagram illustrating the basic principle of phase modulation in LCOS.

[0029] Figure 2 This is a schematic diagram of the structure of a measuring device 200 provided in an embodiment of this application.

[0030] Figure 3 This is a schematic diagram of multi-beam interference provided in an embodiment of this application.

[0031] Figure 4 This is a schematic diagram of the first structure of the measuring device 200 provided in the embodiments of this application.

[0032] Figure 5 This is a schematic diagram of a second structure of the measuring device 200 provided in the embodiments of this application.

[0033] Figure 6 This is a schematic flowchart of the measurement method 600 provided in the embodiments of this application.

[0034] Figure 7 This is a schematic flowchart of the measurement method 700 provided in the embodiments of this application.

[0035] Figure 8This is a schematic block diagram of an apparatus 800 for calculating the phase of an LCOS under test, provided in an embodiment of this application.

[0036] Figure 9 This is a schematic block diagram of an apparatus 900 for calculating the phase of an LCOS under test, provided in an embodiment of this application. Detailed Implementation

[0037] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0038] The following description is provided to facilitate understanding of the embodiments of this application.

[0039] First, the terms "first," "second," and various numerical designations used in the textual descriptions or drawings of the embodiments of this application shown below are merely for descriptive convenience and are not intended to describe a specific order or sequence, nor are they used to limit the scope of the embodiments of this application. For example, in the embodiments of this application, they are used to distinguish different ports of a circulator or to distinguish different lenses.

[0040] Second, the terms “comprising” and “having” and any variations thereof in the embodiments of this application shown below are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products or devices.

[0041] Third, in the embodiments of this application, the words "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Embodiments or designs described as "exemplary" or "for example" should not be construed as being more preferred or advantageous than other embodiments or designs. The use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner for ease of understanding.

[0042] Figure 1 This is the basic principle of phase modulation in LCOS. The liquid crystal layer consists of a silicon backplane, a reflective coating, an alignment layer, a transparent electrode, and a cover glass, with an anti-reflective coating attached to the cover glass. When there is no voltage in the liquid crystal layer, the liquid crystal crystals are aligned in parallel. As the voltage gradually increases and reaches the threshold voltage, the liquid crystal crystals will rotate at a certain angle. Because liquid crystals exhibit birefringence under the influence of an electric field, different electric field strengths will cause the liquid crystal crystals to rotate to different degrees, thereby changing their refractive index and achieving phase modulation of the light beam.

[0043] Due to its excellent passband tuning flexibility, optical network hardware compatibility, and beam deflection stability, LCOS is widely used in WSS (Wavelength Switching). To improve the switching dimension and beam deflection efficiency of WSS, the development of LCOS chips in the communication band mainly focuses on two directions. The first is towards higher resolution and smaller pixel sizes to achieve larger beam deflection angles and increase the wavelength switching dimension. The second is towards higher phase modulation depth to reduce insertion loss and improve WSS performance.

[0044] However, high-resolution, high-modulation-depth LCOS in the communication band suffers from significant edge field effects. Generally, edge field effects arise from the combined effect of the lateral electric field between pixel electrodes and the elastic force of liquid crystal molecules, leading to phase back regions between adjacent pixels. The presence of these phase back regions reduces the far-field diffraction efficiency of the LCOS and introduces non-ideal orders. When applied to WSS (Wireless Sliding Array), this can cause problems such as insertion loss, crosstalk, and polarization. Therefore, to optimize LCOS performance, it is necessary to accurately characterize the LCOS phase profile under the influence of edge field effects.

[0045] Currently, there are two common schemes for obtaining the phase profile of high-resolution, high-modulation-depth LCOS by constructing a precise phase measurement platform. The first is a measurement scheme based on digital holographic microscopy (DHM). This scheme uses measurement light in the communication band, and for high-resolution, small-pixel LCOS, the resolution of this measurement system is significantly insufficient, resulting in a low sampling rate for the phase profile of the LCOS under test, thus failing to accurately depict the phase profile. The second scheme is based on visible light self-interference effects. This scheme uses a simple 4f imaging system, which can only measure the phase of the entire LCOS and cannot measure the phase distribution at the pixel level.

[0046] Therefore, based on the above problems, this application provides a measurement device and method. By adding a microscope objective to the measurement optical path for magnified imaging, the measurement device can measure the pixel-level phase profile of LCOS. At the same time, by utilizing the coating characteristics of LCOS in the communication band, the measurement is performed in the visible light band, and combined with the self-interference effect of coherent light in the visible light band, the optical resolution of the micro-interference measurement is improved, thereby achieving the effect of improving the measurement accuracy of LCOS phase profile.

[0047] Figure 2 This is a schematic diagram of the structure of a measuring device 200 provided in an embodiment of this application. Figure 2As shown, the measuring device 200 is applied to the LCOS 250 under test. Specifically, the measuring device 200 includes: a polarization conversion device 210, a first lens 220, a beam splitter 230, an objective lens 240, and a second lens 260.

[0048] Specifically, after the measurement begins, the polarization conversion device 210 acquires the input coherent beam and converts its polarization direction to match that of the LCOS 250 under test, generating a first beam. This first beam is transmitted along the optical path to the first lens 220, which transmits it to the beam splitter 230. The beam splitter 230 receives the first beam transmitted from the first lens 220 and transmits it to the objective lens 240. The objective lens 240 then transmits the first beam to the LCOS 250 under test. When the first beam transmitted from objective lens 240 reaches the surface of the LCOS 250 under test, due to the semi-transmissive and semi-reflective nature of the LCOS 250, a portion of the first beam is directly reflected by the surface of the LCOS 250, while the other portion is transmitted through the liquid crystal layer of the LCOS 250. The liquid crystal modulates the wavefront phase of this portion of the beam, and after reflection by the reflective coating, it reaches the surface of the LCOS 250 again, generating multi-beam interference with the directly reflected portion, thus producing an interference beam. The process of this multi-beam interference can be found in [reference needed]. Figure 3 The schematic diagram is shown. Subsequently, the interference beam is transmitted through objective lens 240 and reaches beam splitter 230 again. Beam splitter 230 transmits the interference beam to second lens 260 by changing the transmission direction of the interference beam. Second lens 260, receiving the interference beam, transmits the interference beam to detector 280, and detector 280 measures the phase of the LCOS 250 under test based on the interference beam.

[0049] It should be noted that the measuring device 200 provided in this application may not include the light source 270 and the detector 280; an external detector and light source can be used when performing measurements. Alternatively, the measuring device 200 provided in this application may include at least one of 270 and detector 280.

[0050] Whether using the light source within the measuring device 200 itself or an external light source, a laser can be used to generate a coherent beam. It should be understood that for the LCOS under test operating in the communication band, its surface is generally coated with an anti-reflection film to increase transmittance in the communication band. This anti-reflection film has high transmittance in the communication band but poor transmittance in the visible light band. Therefore, when performing measurements, a visible light laser can be used to generate a coherent beam in the visible light band instead of a coherent beam in the communication band. The advantage of this is that it can overcome the diffraction-limited resolution in communication band measurements, thereby achieving sub-pixel-level phase measurement of the LCOS and improving measurement accuracy.

[0051] Furthermore, in this embodiment, the polarization conversion device 210 may be a linear polarizer or other optical element capable of changing the polarization direction of a coherent beam, such as a birefringent crystal, etc., and this application is not limited thereto. The detector 280 may be a CCD image sensor or a CMOS image sensor.

[0052] It should be understood that in the measuring device 200 provided in this application embodiment, the distance between the first lens 220 and the objective lens 240 should be greater than the focal length of the first lens 220, that is, the focal plane of the first lens is located between the first lens 220 and the objective lens 240. For example, when the focal plane of the first lens coincides with the back focal plane of the objective lens 240, the first beam can exit the objective lens 240 in parallel, thereby improving the utilization efficiency of the beam during measurement.

[0053] In addition, the LCOS to be measured should be within the working distance of the objective lens 240 to ensure the accuracy and reliability of the measurement.

[0054] In one possible implementation, the beam splitter 230 can be a beam splitter, such as... Figure 4 As shown. Specifically, the beam splitter first transmits the transmitted portion of the first beam transmitted by the first lens 220 to the objective lens 240, and reflects the coherent beam from the objective lens 240 to the second lens 260.

[0055] In another possible implementation, the beam splitter 230 can be a spatial circulator, such as... Figure 5 As shown. Specifically, the circulator consists of a first polarization beam splitter (PBS) combination prism 231, a Faraday rotator 232, a half-wave plate 233, and a second PBS combination prism 234. Through port 1 (i.e.... Figure 5 Port 2 (numbered 1) receives the first beam transmitted by the first lens 220. The first beam passes through the Faraday rotator 232 and the half-wave plate 233, and is reflected by the second PBS combined prism 234 before exiting from port 2 to the objective lens 240. At the same time, port 2 receives the interference beam transmitted from the objective lens 240. After passing through the Faraday rotator 232 and the half-wave plate 233, the interference beam is output from port 3 through the first PBS combined prism 231 to the second lens 260.

[0056] It should be understood Figure 5 The spatial circulator described is merely an example and not a limitation. Other spatial circulators that can implement the embodiments of this application are all within the protection scope of this application.

[0057] Optionally, to further improve the accuracy of the measurement, in such cases... Figure 2The measuring device 200 shown may also include optical elements such as collimating lenses or isolators. For example, a collimating lens may be placed between the light source 270 and the polarization conversion device 210 to collimate the coherent beam emitted from the light source. Alternatively, an isolator may be added between the polarization conversion device 210 and the first lens 220 to isolate reflected light from the rear optical elements.

[0058] The above, combined with Figures 2 to 5 The measuring device provided in the embodiments of this application is described in detail below. Figure 6 and Figure 7 The measurement methods provided in the embodiments of this application are described in detail.

[0059] It should be noted that in the measurement method provided in this application embodiment, the coherent beams are all coherent beams in the visible light band, that is, the measuring device uses visible light to acquire the interference pattern. The execution subject of the measurement method provided in this application embodiment is an image processing device or a processing device, such as a processor. Specifically, after the detector 280 receives the interference beam, it converts the optical signal into a digital electrical signal and transmits it to the image processing device for image processing, whereby the image processing device completes the phase calculation of the LCOS under test.

[0060] In one feasible way, combining Figure 2 The measuring devices shown are 200 pairs. Figure 6 The measurement method 600 shown is explained in detail. For example... Figure 6 As shown, the method 600 includes the following steps.

[0061] S601, obtain N interference patterns.

[0062] Specifically, refer to Figure 2 The measuring device 200 loads N uniform phase maps onto the LCOS 250 under test, so that the detector 280 receives the interference pattern corresponding to each phase map and sends it to the image processing device, where N is an integer greater than 1. For example, phase maps of 0-2π are loaded onto the LCOS 250 under test, and the detector 280 collects interference patterns under different phase modulations and transmits them to the image processing device.

[0063] S602 generates the correspondence between the interference intensity and phase of each pixel of the detector based on N interferometric patterns.

[0064] Specifically, the image processing device extracts the correspondence between the interference intensity and phase of each pixel of the detector 280 based on the acquired N interference patterns, and calibrates the curve of interference intensity and phase corresponding to each pixel of the detector 280.

[0065] Optionally, when acquiring N interference patterns, it is also possible to iterate through all gray levels of the LCOS 250 under test, so that the calibrated curve can also reflect the correspondence between the interference intensity and phase of each pixel point of the LCOS 250 under test in all gray levels.

[0066] S603, acquire the interference pattern of the phase image to be measured.

[0067] Specifically, the phase map of the grating to be measured is loaded onto the LCOS 250 under test, and the image processing device acquires the interference pattern under the phase map of the grating under test at this time through the detector 280.

[0068] S604 determines the phase profile of the LCOS under test by loading the phase map of the test based on the relationship between the interference intensity and phase of each pixel of the detector.

[0069] Specifically, the image processing device searches for the corresponding interference intensity and phase curve calibrated in S602 based on the interference intensity under the acquired phase map of the grating to be tested, and obtains the phase of the grating to be tested. The phase of the grating to be tested is the phase of the LCOS 250 to be tested.

[0070] If N interference patterns are acquired, and all gray levels of the LCOS 250 under test are also traversed, a situation may arise where one intensity corresponds to multiple gray levels during phase lookup. In this case, it is necessary to select the phase based on the phase gradient of the grating. For example, if the phase corresponding to a certain intensity is near the lowest phase of the loaded grating under test, the phase corresponding to the highest gray value can be selected as the phase of the LCOS 250 under test at that intensity. If the phase corresponding to a certain intensity is near the highest phase of the loaded grating under test, the phase corresponding to the lowest gray value can be selected as the phase of the LCOS 250 under test at that intensity.

[0071] Based on the above scheme, this embodiment utilizes the phase modulation characteristics of LCOS itself to calibrate the interference intensity and phase, thus avoiding the introduction of a precision stepping platform, reducing measurement costs, and improving measurement reliability. This phase measurement method enables accurate phase measurement of LCOS with high modulation depth, small pixels, and high resolution, further optimizing the establishment of the LCOS phase model and the LCOS phase algorithm.

[0072] It should be noted that, in order to ensure the accuracy and reliability of the measurement, in the measurement method 600 provided in this application embodiment, the jitter of the detector 280 when acquiring the interference pattern should be less than 5% of the peak-to-peak value of the measured interference intensity. Typically, denoising can be performed during image processing using filtering algorithms such as frequency domain filtering, time domain filtering, or mean filtering.

[0073] In another feasible approach, combining Figure 2 The measuring device shown is for Figure 7 The measurement method 700 shown is explained in detail. For example... Figure 7 As shown, the method 700 includes the following steps.

[0074] For S701-S702, please refer to the descriptions of S601-S602 above, which will not be repeated here.

[0075] S703 generates the phase-grayscale correspondence of the visible light band based on the correspondence between the interference intensity and phase of each pixel of the detector.

[0076] Specifically, the image processing device converts the curve of interference intensity versus phase for each pixel of the detector into a phase versus grayscale mapping curve in the visible light band.

[0077] S704 converts the phase-to-grayscale correspondence of the visible light band into the phase-to-grayscale correspondence of the communication band.

[0078] Specifically, the image processing device converts the correspondence between phase and gray level in the visible light band into a phase-gray level mapping curve in the communication band using the following formula (1).

[0079]

[0080] in, The wavelength of visible light. The wavelength of the communication band. The phase corresponding to a certain gray level under visible light. For communication bands corresponding to phase, For the liquid crystal material of the LCOS under test in The difference in refractive index between the e-ray and the o-ray. For the liquid crystal material of the LCOS under test in The difference in refractive index between the e-ray and the o-ray.

[0081] S705, acquire the interference pattern of the phase image to be measured.

[0082] Specifically, the phase map of the grating to be measured is loaded onto the LCOS 250 under test, and the image processing device acquires the interference pattern under the phase map of the grating under test at this time through the detector 280.

[0083] S706, based on the correspondence between phase and grayscale of the communication band, determines the phase profile of the LCOS under test with the phase map to be loaded.

[0084] Specifically, the image processing device searches for the corresponding phase-to-grayscale mapping curve of the communication band calibrated in S704 based on the interference intensity under the acquired phase map of the grating to be tested, and obtains the phase of the grating to be tested, which is the phase of the LCOS 250 to be tested.

[0085] Similarly, when acquiring N interferograms, all gray levels of the LCOS 250 under test can be traversed. Meanwhile, to ensure the accuracy and reliability of the measurement, the jitter of the detector 280 when acquiring the interferograms should be less than 5% of the peak-to-peak value of the measured interferometric intensity.

[0086] Based on the above scheme, the measurement method provided in this application embodiment can be compatible with the measurement of communication bands and realize multi-band measurement.

[0087] The method embodiments of this application have been described above with reference to the accompanying drawings. The apparatus embodiments for calculating the phase of the LCOS to be measured, as described above, are described below. It is understood that the descriptions of the method embodiments and the apparatus embodiments for calculating the phase of the LCOS to be measured can correspond to each other; therefore, any parts not described can be referred to the preceding method embodiments.

[0088] It is understood that the methods and operations implemented by the apparatus for calculating the LCOS phase under test in the above-described method embodiments can also be implemented by components (e.g., chips) of the apparatus for calculating the LCOS phase under test.

[0089] Figure 8 This is a schematic block diagram of an apparatus 800 for calculating the phase of an LCOS under test, provided in an embodiment of this application. Figure 8 As shown, the apparatus 800 for calculating the phase of the LCOS under test includes an acquisition module 810, a processing module 820, and a display module 830. The acquisition module 810 is used to acquire interferometric patterns from the detector. The acquisition module 810 also includes a communication interface or electrical connection module. The acquisition module 810 is used to implement... Figure 6 S601 or Figure 7 S701 in the example. This processing module 820 is used to implement... Figure 6 S602-S604 in the middle, or implementation Figure 7 S702-S706 in the example. This display module 830 is used to display... Figure 6 Phase profile of the LCOS under test in S604, or Figure 7 Phase profile of the LCOS under test in S706.

[0090] like Figure 9As shown in the illustration, this application also provides a schematic block diagram of an apparatus 900 for calculating the phase of an LCOS under test. The apparatus 900 for calculating the phase of an LCOS under test includes a processor 910 coupled to a memory 920. The memory 920 is used to store computer programs or instructions and / or data. The processor 910 is used to execute the computer programs or instructions and / or data stored in the memory 920, causing the methods in the above method embodiments to be executed.

[0091] Optionally, the apparatus 900 for calculating the phase of the LCOS under test may include one or more processors 910.

[0092] Optionally, the device 900 for calculating the phase of the LCOS under test may include one or more memories 920.

[0093] Alternatively, the memory 920 can be integrated with the processor 910 or set separately.

[0094] Optionally, such as Figure 9 As shown, the apparatus 900 for calculating the phase of the LCOS under test may further include a transceiver 930 and / or a communication interface, which are used for receiving and / or transmitting signals. For example, a processor 910 is used to control the transceiver 930 and / or the communication interface to receive and / or transmit signals.

[0095] The processing module 820 in the device 800 for calculating the phase of the LCOS under test can be... Figure 9 The processor 910 and the acquisition module 810 can be used as processors 910 and 810 respectively. Figure 9 The transceiver 930 is described in detail above. For the specific operations performed by the processor 910, please refer to the description of the processing module 820 above. For the operations performed by the transceiver 930, please refer to the description of the acquisition module 810. They will not be repeated here.

[0096] This application also provides a computer storage medium storing software programs. When read and executed by one or more processors, these software programs can implement the methods provided in any one or more of the above embodiments. The computer storage medium may include various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory, random access memory, magnetic disks, or optical disks.

[0097] This application also provides a chip, which includes a processor for implementing the functions involved in any one or more of the above embodiments, such as detecting whether the combined optical signal carries first modulation information. Optionally, the chip further includes a memory for storing necessary program instructions and data executed by the processor. This chip can be composed of individual chips or can include chips and other discrete devices.

[0098] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0099] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0100] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0101] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0102] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0103] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0104] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0105] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0106] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0107] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0108] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A device for measuring, characterized by, Applied to silicon-based liquid crystal LCOS under test, it includes: a polarization conversion device, a first lens, a beam splitter, an objective lens, and a second lens. The polarization conversion device is used to acquire the input coherent beam and convert the polarization direction of the coherent beam into the polarization direction of the silicon-based liquid crystal LCOS under test, thereby generating a first beam. The first lens is used to transmit the first light beam to the beam splitter element; The beam splitter is used to transmit the first beam emitted from the first lens to the objective lens, and to transmit the interference beam from the objective lens to the second lens; The objective lens is used to transmit the first light beam emitted from the beam splitter to the silicon-based liquid crystal LCOS under test, and to transmit an interference beam from the silicon-based liquid crystal LCOS under test to the beam splitter. The interference beam is generated by the silicon-based liquid crystal LCOS under test based on the first light beam emitted from the objective lens. The second lens is used to transmit the interference beam emitted from the beam-splitting element to the detector, so that the detector can measure the phase of the silicon-based liquid crystal LCOS under test based on the interference beam. The coherent beam is a laser beam with a visible light wavelength, and the operating wavelength of the silicon-based liquid crystal LCOS under test is a communication band wavelength.

2. The apparatus of claim 1, wherein, The objective lens is a microscope objective lens.

3. The apparatus according to claim 1 or 2, characterized in that, The distance between the objective lens and the first lens is greater than the focal length of the first lens.

4. The apparatus of claim 1 or 2, wherein, The beam-splitting element is a beam splitter or an optical circulator.

5. A method of measurement, characterized by, Based on the apparatus of any one of claims 1 to 4, the method comprises: N interference patterns are obtained, and the N interference patterns correspond to the N phase patterns loaded on the silicon-based liquid crystal LCOS under test; Based on the N interferograms, the correspondence between the interference intensity and phase of each pixel of the detector is generated; Obtain the interferogram of the phase image to be measured; Based on the correspondence between the interference intensity and phase of each pixel of the detector, the phase profile of the silicon-based liquid crystal LCOS under test with the phase map to be tested loaded is determined, where N is an integer greater than 1.

6. The method of claim 5, wherein, The method further includes: The phase-grayscale correspondence of the visible light band is generated based on the correspondence between the interference intensity and phase of each pixel of the detector. The phase-to-grayscale correspondence of the visible light band is converted into the phase-to-grayscale correspondence of the communication band. The determination of the phase profile of the silicon-based liquid crystal LCOS under test, based on the correspondence between the interference intensity and phase of each pixel of the detector, and the loading of the phase map to be tested, includes: Based on the correspondence between the phase and grayscale of the communication band, the phase profile of the silicon-based liquid crystal LCOS under test is determined by loading the phase map under test.

7. The method according to claim 5 or 6, characterized in that, The N interference patterns correspond to N gray levels and N phases.

8. The method according to claim 5 or 6, characterized in that, The acquisition of N interference patterns includes: The N interference patterns are obtained by using a coherent beam of light in the visible light band.

9. The method according to claim 5 or 6, characterized in that, The operating wavelength of the silicon-based liquid crystal LCOS under test is the communication band wavelength.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store a computer program that, when run on a computer including one or more processors, causes the computer to perform the method as described in any one of claims 5 to 9.

11. A computer program product, characterised in that, The computer program product includes: computer program code, which, when run, implements the method as described in any one of claims 5 to 9.

12. A chip, characterized by It includes a processor and a memory, the memory being used to store a computer program, and the processor being used to invoke and run the computer program stored in the memory to perform the method as described in any one of claims 5 to 9.

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