An exposure apparatus based on a spatial phase modulator and a liquid crystal device

Abstract

The application relates to an exposure device based on a spatial phase modulator and a liquid crystal device, which comprises a light source control module, a light intensity and polarization control module, a focusing servo module, a sample setting module, a voltage control module and a monitoring module, the light source control module comprises a first switchable mirror and a light source switching assembly, the light intensity and polarization control module comprises a light intensity modulation assembly for receiving a light beam output by the light source control module and modulating the light intensity of each pixel point in the light beam, and a polarization modulation assembly for modulating the polarization state of each pixel point in the light beam emitted by the light intensity modulation assembly; the first switchable mirror is used for switching the light path between the light intensity modulation assembly and the polarization modulation assembly; the focusing servo module and the sample setting module are both switched to face the polarization modulation assembly or the first switchable mirror. Compared with the prior art, the exposure device has more degrees of freedom, the exposure process is simple and efficient, and the needs of experimental teaching and scientific research engineering can be met.

Description

Technical Field

[0001] This invention relates to the field of exposure apparatus, and more particularly to an exposure apparatus based on a spatial phase modulator and a liquid crystal device. Background Technology

[0002] Photoalignment technology is a high-end technology for achieving contactless alignment of liquid crystals. It utilizes the characteristic of photoalignment materials responding to linearly polarized light; that is, under saturated light dose, their alignment direction rotates within the substrate plane to be perpendicular to the linear polarization direction of the light. Upon contact with the injected liquid crystal molecules, the photoalignment material induces the liquid crystal molecules to align in an orderly manner, thereby achieving regional alignment of the liquid crystal molecules. Pixelated distribution of liquid crystal alignment can be achieved by constructing a pixelated distribution of light polarization states.

[0003] While existing exposure devices can achieve pixelated distribution of liquid crystal alignment, they each have their own disadvantages. For example, digital exposure machines based on digital micromirror devices (DMDs) can independently control the micromirrors in each pixel unit, allowing them to rotate the mirror angle through mechanical manipulation to reflect light to a designated exposure area (1) or outside the designated exposure area (0). The exposure area is 1 when there is light and 0 when there is no light. Combined with a rotatable linear polarization device to generate a specific linear polarization angle, pixelated distribution of liquid crystal alignment is achieved by pixel addressing and re-exposure for each alignment angle. However, such devices usually use multi-step exposure, and the number of exposures is related to the number of alignment angles. If the number of alignment angles is large, such devices are very time-consuming and inefficient.

[0004] Therefore, another type of exposure machine based on LCoS emerged. This device incorporates a quarter-wave plate into the LCoS optical path. By manipulating the LCoS, the linear polarization state of the emitted light is distributed in a pixelated manner across the beam cross-section, thus enabling rapid and efficient pixelated exposure for liquid crystal alignment. Examples include the large-format controllable polarization pattern generation device disclosed in utility model CN201921985644, and the patterned liquid crystal light alignment device based on orthogonal circularly polarized light interference disclosed in utility model CN201921982615. However, this device also has some drawbacks. For instance, it can only control the linear polarization direction of each pixel in the beam, but not the light intensity of each pixel. In other words, light shines on the sample from every pixel, which can cause problems in some applications. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art, which can only control the linear polarization direction of each pixel in the light beam but cannot control the light intensity of each pixel, and to provide an exposure device based on a spatial phase modulator and a liquid crystal device.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] An exposure apparatus based on a spatial phase modulator and a liquid crystal device includes a focusing servo module, a sample placement module, and a voltage control module. The apparatus further includes a light source control module and a light intensity and polarization control module. The light source control module includes a first switchable mirror and a light source switching component for switching between different color light sources.

[0008] The light intensity and polarization control module includes:

[0009] The light intensity modulation component is used to receive the light beam output by the light source control module and modulate the light intensity of each pixel in the light beam;

[0010] A polarization modulation component is used to modulate the polarization state of each pixel in the beam emitted by the light intensity modulation component;

[0011] The first switchable mirror is located between the light intensity modulation component and the polarization modulation component, and is used to switch the optical path entering or exiting between the light intensity modulation component and the polarization modulation component.

[0012] Both the focusing servo module and the sample placement module switch between the output optical path facing the polarization modulation component and the reflected optical path facing the first switchable mirror via motion control components.

[0013] Furthermore, when the first switchable mirror exits the optical path between the intensity modulation component and the polarization modulation component, and the focusing servo module and the sample placement module are aligned with the output optical path of the polarization modulation component,

[0014] The light beam generated by the light source switching component passes sequentially through the light intensity modulation component and the polarization modulation component, and then enters the focusing servo module, thereby independently modulating the light intensity and linear polarization direction of each pixel in the light beam reflected by the polarization beam splitter.

[0015] Furthermore, when the first switchable mirror enters the optical path between the intensity modulation component and the polarization modulation component, and the focusing servo module and the sample placement module are aligned with the reflected optical path of the first switchable mirror,

[0016] The light beam generated by the light source switching component enters the focusing servo module after passing through the light intensity modulation component, thereby independently modulating the light intensity of each pixel in the light beam.

[0017] Furthermore, the light intensity modulation component is a reflective light intensity modulation structure or a transmissive light intensity modulation structure; the polarization modulation component is a reflective polarization modulation structure or a transmissive polarization modulation structure.

[0018] Furthermore, the reflective light intensity modulation structure includes a first spatial phase modulator and a first polarization beam splitter arranged in sequence. The light beam generated by the light source switching component passes through the first polarization beam splitter and the first spatial phase modulator in sequence and then exits in the direction of the polarization modulation component.

[0019] The transmissive light intensity modulation structure includes a first polarizer, a first transmissive liquid crystal panel, and a second polarizer arranged in sequence. The light beam generated by the light source switching component passes through the first polarizer, the first transmissive liquid crystal panel, and the second polarizer in sequence, and then exits in the direction of the polarization modulation component.

[0020] The reflective polarization modulation structure includes a first electrically controlled liquid crystal waveplate, a second polarization beam splitter, a second spatial phase modulator, and a second electrically controlled liquid crystal waveplate. The light beam emitted from the light intensity modulation component passes sequentially through the first electrically controlled liquid crystal waveplate, the second polarization beam splitter, the second spatial phase modulator, and the second electrically controlled liquid crystal waveplate before being emitted toward the focusing servo module.

[0021] The transmissive polarization modulation structure includes a second transmissive liquid crystal panel, a third electronically controlled liquid crystal waveplate, and a fixed reflector arranged in sequence. The light beam emitted from the light intensity modulation component passes through the second transmissive liquid crystal panel, the third electronically controlled liquid crystal waveplate, and the fixed reflector in sequence before being emitted toward the focusing servo module.

[0022] Furthermore, the voltage control module includes a multi-channel voltage signal generator and a signal control device. The first, second, and third electronically controlled liquid crystal waveplates are all electrically connected to the multi-channel voltage signal generator via metal wires. The first transmissive liquid crystal panel, the second transmissive liquid crystal panel, the first spatial phase modulator, and the second spatial phase modulator are all electrically connected to the signal control device via data lines.

[0023] Furthermore, the light source switching component includes a main light source, a secondary light source, and a second switchable reflector. The wavelength of the main light source is within the range of 300-500 nanometers or 600-1000 nanometers. The main light source and the secondary light source have different beam colors. The main light source is directly opposite the input end of the light intensity modulation component, and the second switchable reflector is directly opposite the secondary light source. It is used to switch the light path between the main light source and the light intensity modulation component, thereby switching the main light source and the secondary light source.

[0024] Furthermore, the light source switching component includes a white light source and a detachable color filter, which is used to insert different color filters under the white light source to achieve switching between different color light sources.

[0025] Furthermore, the sample placement module includes an adjustment platform, a sample exposure base, and a liquid crystal cell sample. The adjustment platform is provided with a slide rail for the sample exposure base to slide on, and the liquid crystal cell sample is mounted on the sample exposure base.

[0026] The liquid crystal cell sample includes an upper substrate, a lower substrate, and a liquid crystal cell. Both the upper substrate and the lower substrate are provided with transparent conductive electrodes. At least one of the upper substrate and the lower substrate is coated with a photoalignment layer. The upper substrate and the lower substrate are respectively connected to the two ends of the liquid crystal cell and form a Z-shaped structure.

[0027] The sample exposure base has a Z-shaped groove. One end of the Z-shaped groove has a step at the bottom and a protrusion at the top of the other side. A first metal conductive contact is provided on the step for contacting the transparent conductive electrode of the upper substrate. The Z-shaped groove also has an elastic buckle at the top of the step for limiting the position of the liquid crystal cell sample. A second metal conductive contact is provided at the bottom of the protrusion for contacting the transparent conductive electrode of the lower substrate. Both the first and second metal conductive contacts are electrically connected to the voltage control module through metal wires.

[0028] Furthermore, the exposure device also includes a monitoring module, which includes a switchable semi-transparent mirror and a camera, wherein the camera is a CCD camera or a CMOS camera. The switchable semi-transparent mirror is located between the focusing servo module and the sample placement module, and is used to switch the optical path between the focusing servo module and the sample placement module, reflecting the light beam reflected by the sample placement module into the camera.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] This invention grants the exposure device greater freedom. Besides manipulating the linear polarization direction of each pixel in the light beam for rapid and efficient pixelated exposure of liquid crystal alignment, it also enables simultaneous multi-grayscale control of the light intensity of each pixel from 0 to 1. The exposure modes of this invention can be flexibly switched, and the exposure process is simple and efficient, meeting various application requirements. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of an exposure apparatus based on a spatial phase modulator and a liquid crystal device provided in an embodiment of the present invention;

[0032] Figure 2 This is a first structural schematic diagram of an exposure apparatus based on a spatial phase modulator and a liquid crystal device provided in an embodiment of the present invention;

[0033] Figure 3This is a schematic diagram of the second structure of an exposure apparatus based on a spatial phase modulator and a liquid crystal device provided in an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the structure of a liquid crystal cell sample provided in an embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the third structure of an exposure apparatus based on a spatial phase modulator and a liquid crystal device provided in an embodiment of the present invention;

[0036] Figure 6 This is a schematic diagram of the third structure of an exposure apparatus based on a spatial phase modulator and a liquid crystal device provided in an embodiment of the present invention;

[0037] Figure 7 This is a schematic diagram of the third structure of an exposure apparatus based on a spatial phase modulator and a liquid crystal device provided in an embodiment of the present invention;

[0038] In the diagram, 1. Light source control module; 100. Main light source; 101. Secondary light source; 102. Second switchable reflector; 103. First switchable reflector; 2. Light intensity and polarization control module; 200. First spatial phase modulator; 201. Second spatial phase modulator; 202. First polarizing beam splitter prism; 203. Second polarizing beam splitter prism; 204. First electrically controlled liquid crystal waveplate; 205. Second electrically controlled liquid crystal waveplate; 206. 4f optical system; 207. First polarizer; 208. First transmissive liquid crystal panel; 209. Second polarizer; 210. Second transmissive liquid crystal panel; 211. Third electrically controlled liquid crystal waveplate; 212. Fixed reflector; 3. 300. Focusing servo module; 4. Lens group and focusing servo; 5. Sample placement module; 6. Liquid crystal cell sample; 7. Substrate with transparent conductive electrode; 8. Liquid crystal material or liquid crystal material doped with photosensitizer; 9. Friction alignment layer or photoalignment layer; 10. Friction alignment layer or photoalignment layer; 11. Adjustment platform; 2. Flexible metal conductive contact; 3. Elastic snap-fit; 4. Voltage control module; 5. Multi-channel voltage signal generator; 6. Computer or signal controller; 7. Monitoring module; 8. Switchable semi-transparent and semi-reflective mirror; 9. CCD camera or CMOS camera. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0041] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0042] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed during use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0043] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0044] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0045] Example 1

[0046] like Figure 1As shown, this embodiment provides an exposure device based on a spatial phase modulator and a liquid crystal device, including a focusing servo module 3, a sample placement module 4, and a voltage control module 5. The exposure device also includes a light source control module 1 and a light intensity and polarization control module 2. The light source control module 1 includes a first switchable reflector 103 and a light source switching component for switching between different color light sources.

[0047] Light intensity and polarization control module 2 includes:

[0048] The light intensity modulation component is used to receive the light beam output by the light source control module 1 and independently modulate the light intensity of each pixel in the light beam;

[0049] A polarization modulation component is used to independently modulate the polarization state of each pixel in the beam emitted by the light intensity modulation component;

[0050] The first switchable mirror 103 is located between the light intensity modulation component and the polarization modulation component, and is used to switch the optical path between the light intensity modulation component and the polarization modulation component.

[0051] Both the focusing servo module 3 and the sample placement module 4 are switched via motion control components to face either the output optical path of the polarization modulation component or the reflected optical path of the first switchable mirror 103. The relative positions of the focusing servo module 3 and the sample placement module 4 are fixed.

[0052] The aforementioned polarization modulation component can be implemented using a polarization pattern generating component in a large-format controllable polarization pattern generating device disclosed in utility model publication CN201921985644, or a polarization pattern generating component in a patterned liquid crystal light alignment device based on orthogonal circularly polarized light interference disclosed in utility model publication CN201921982615, or other components that can adjust the polarization state of each pixel in the light beam.

[0053] By switching the first switchable reflector 103, the focusing servo module 3, and the sample placement module 4, the light intensity and polarization state of each pixel in the beam can be modulated by the light intensity modulation component and the polarization modulation component; the light intensity of each pixel in the beam can be modulated by the light intensity modulation component.

[0054] The light intensity modulation component is a reflective light intensity modulation structure or a transmissive light intensity modulation structure; the polarization modulation component is a reflective polarization modulation structure or a transmissive polarization modulation structure.

[0055] Specifically, the reflective light intensity modulation structure includes a first spatial phase modulator 200 and a first polarization beam splitter 202 arranged in sequence. The light beam generated by the light source switching component passes through the first polarization beam splitter 202 and the first spatial phase modulator 200 in sequence and then exits in the direction of the polarization modulation component.

[0056] The transmissive light intensity modulation structure includes a first polarizer 207, a first transmissive liquid crystal panel 208, and a second polarizer 209 arranged in sequence. The light beam generated by the light source switching component passes through the first polarizer 207, the first transmissive liquid crystal panel 208, and the second polarizer 209 in sequence before being emitted in the direction of the polarization modulation component.

[0057] The reflective polarization modulation structure includes a first electrically controlled liquid crystal waveplate 204, a second polarization beam splitter 203, a second spatial phase modulator 201, and a second electrically controlled liquid crystal waveplate 205. The light beam emitted from the light intensity modulation component passes sequentially through the first electrically controlled liquid crystal waveplate 204, the second polarization beam splitter 203, the second spatial phase modulator 201, and the second electrically controlled liquid crystal waveplate 205 before being emitted toward the focusing servo module 3.

[0058] The transmissive polarization modulation structure includes a second transmissive liquid crystal panel 210, a third electronically controlled liquid crystal waveplate 211, and a fixed reflector 212 arranged in sequence. The light beam emitted from the light intensity modulation component passes through the second transmissive liquid crystal panel 210, the third electronically controlled liquid crystal waveplate 211, and the fixed reflector 212 in sequence before being emitted toward the focusing servo module 3.

[0059] The overall light intensity and polarization control module 2 can realize four combinations: reflective light intensity modulation structure + reflective polarization modulation structure, reflective light intensity modulation structure + transmissive polarization modulation structure, transmissive light intensity modulation structure + reflective polarization modulation structure, and transmissive light intensity modulation structure + transmissive polarization modulation structure.

[0060] like Figure 2 and 3 As shown, this embodiment adopts a light intensity and polarization control module structure of reflective light intensity modulation structure + reflective polarization modulation structure. The first spatial phase modulator 200 and the second spatial phase modulator 201 can both adopt LCoS structure or SLM structure. The first electronically controlled liquid crystal waveplate 204 and the second electronically controlled liquid crystal waveplate 205 are both electronically tunable QWP@450 / 550nm models, which can be set according to specific application requirements and are not limited to one.

[0061] The beam intensity modulation component can be added to the 4f optical system 206 for beam optimization.

[0062] Specifically, in this embodiment, the light intensity modulation component includes a first spatial phase modulator 200, a first polarization beam splitter prism 202 and a 4f optical system 206 arranged sequentially, and the polarization modulation component includes a first electronically controlled liquid crystal waveplate 204, a second polarization beam splitter prism 203, a second spatial phase modulator 201 and a second electronically controlled liquid crystal waveplate 205.

[0063] The exposure device in this solution can achieve two working modes:

[0064] Working Mode 1: When the light source switching component switches to the main light source, the light intensity and polarization control module can switch working modes through a mechanical push-pull reflector 103.

[0065] When the first switchable mirror 103 exits the optical path between the light intensity modulation component and the polarization modulation component, and the focusing servo module 3 and the sample placement module 4 are aligned with the output optical path of the polarization modulation component...

[0066] Both the first spatial phase modulator 200 and the second spatial phase modulator 201 are in operation. The light beam generated by the light source switching component passes sequentially through the first polarizing beam splitter prism 202, the first spatial phase modulator 200, the 4f optical system 206, the first electro-hydraulic waveplate 204, the second polarizing beam splitter prism 203, the second spatial phase modulator 201, and the second electro-hydraulic waveplate 205, thereby independently modulating the polarization state of each pixel in the light beam reflected by the polarizing beam splitter prism. At this time, the phase delay of the first electro-hydraulic waveplate 204 and the second electro-hydraulic waveplate 205 satisfies the quarter-wavelength condition of the 450 nm wavelength of the main light source. Thus, the light beam emitted from the second electro-hydraulic waveplate 205 is then exposed onto the liquid crystal cell sample 401 by the focusing servo module 3 and the monitoring module 6, which are fixed in relative position to the sample placement module 4. In this working mode, the light intensity and linear polarization direction of each pixel in the exposure area can be independently controlled simultaneously.

[0067] Operating Mode Two: When the light source switching component switches to secondary light source operation, the first switchable reflector 103 enters the optical path between the light intensity modulation component and the polarization modulation component. When the focusing servo module 3 and the sample placement module 4 are directly facing the reflected optical path of the first switchable reflector 103,

[0068] Only the first spatial phase modulator 200 is operational, allowing modulation of the light intensity of each pixel in the beam. Furthermore, the beams emitted from the polarizing beam splitter 202 are all linearly polarized. The beam generated by the light source switching component is reflected sequentially by the first polarizing beam splitter 202, the first spatial phase modulator 200, the 4f optical system 206, and the first switchable mirror 103, before being exposed onto the liquid crystal cell sample 401 via the focusing servo module 3 and the monitoring module 6, which are fixed in relative positions to the sample placement module 4. In this operating mode, the light intensity of each pixel in the exposure area can be independently controlled.

[0069] The first switchable reflector 103 mentioned above is a mechanical push-pull reflector.

[0070] As an optional implementation, the voltage control module 5 includes a multi-channel voltage signal generator 500 and a signal control device. The first electronically controlled liquid crystal waveplate 204 and the second electronically controlled liquid crystal waveplate 205 are both electrically connected to the multi-channel voltage signal generator 500 through metal wires, and the first spatial phase modulator 200 and the second spatial phase modulator 201 are both electrically connected to the signal control device through data lines.

[0071] The voltage control module 5 also includes a circuit with adjustable resistors for controlling the signal voltages of the first spatial phase modulator 200, the second spatial phase modulator 201, the first electronically controlled liquid crystal waveplate 204, the second electronically controlled liquid crystal waveplate 205, and the liquid crystal cell sample 401.

[0072] Signal control equipment can be a computer or a signal controller.

[0073] The light source switching component includes a main light source wavelength and a green or other colored secondary light source. The main and secondary light sources can be switched using a switchable reflector, or by inserting different color filters under a white light source to achieve switching between different colors. The specific implementation method is as follows:

[0074] One implementation method for the light source switching component: The light source switching component includes a main light source 100, a secondary light source 101, and a second switchable reflector 102. The wavelength of the main light source 100 is within the range of 300-500 nanometers. If a femtosecond laser is used, two-photon technology can also be utilized. The wavelength range of the femtosecond laser can be within the range of 600-1000 nanometers. The beam colors of the main light source 100 and the secondary light source 101 are different. The main light source 100 faces the input end of the light intensity modulation component, and the second switchable reflector 102 faces the secondary light source 101. It is used to switch the optical path between the main light source 100 and the light intensity modulation component, thereby switching the main light source 100 and the secondary light source 101.

[0075] Method 2 for implementing the light source switching component: The light source switching component includes a white light source and detachable color filters, which are used to insert different color filters under the white light source to achieve switching between different color light sources.

[0076] As an optional implementation, the focusing servo module 3 includes a lens group and a focusing servo 300.

[0077] As an optional implementation, the sample placement module 4 includes an adjustment platform 402, a sample exposure base 400, and a liquid crystal cell sample 401. The adjustment platform 402 is provided with a slide rail for the sample exposure base 400 to slide, and the liquid crystal cell sample 401 is mounted on the sample exposure base 400.

[0078] Specifically, the liquid crystal cell sample 401 includes an upper substrate, a lower substrate, and a liquid crystal cell. Both the upper substrate and the lower substrate are provided with transparent conductive electrodes. At least one of the upper substrate and the lower substrate is coated with a photoalignment layer. The upper substrate and the lower substrate are respectively connected to the two ends of the liquid crystal cell and form a Z-shaped structure.

[0079] The liquid crystal cell is made of liquid crystal material or liquid crystal material doped with photosensitizer;

[0080] Both the upper substrate and the lower substrate have a triboelectric alignment layer or a photoalignment layer on the side closest to the liquid crystal cell.

[0081] like Figure 4 As shown, both the upper and lower substrates are substrates 4011 containing transparent conductive electrodes, the liquid crystal cell is a liquid crystal material or a liquid crystal material doped with a photosensitizer 4012, the top surface of the lower substrate is provided with a rubbing alignment layer or a photoalignment layer 4013, and the bottom surface of the upper substrate is provided with a rubbing alignment layer or a photoalignment layer 4014.

[0082] The adjustment platform 402 is equipped with a slide rail for the sample exposure base 400 to slide, or it is also equipped with a stepper motor to control the sliding of the sample exposure base 400.

[0083] The sample exposure base 400 is provided with a Z-shaped groove and a pair of elastic metal conductive contacts 403. One end of the Z-shaped groove has a step at the bottom and a protrusion at the top of the other side. The first metal conductive contact is provided on the step for contacting the transparent conductive electrode of the upper substrate. The Z-shaped groove is also provided with an elastic buckle 404 located at the top of the step for limiting the position of the liquid crystal cell sample 401. The bottom of the protrusion is provided with a second metal conductive contact for contacting the transparent conductive electrode of the lower substrate. The first and second metal conductive contacts are electrically connected to the voltage control module 5 through metal wires.

[0084] One metal conductive contact 403 holds the exposed transparent conductive electrode on one side of the liquid crystal cell sample 401 in place, while another metal conductive contact 403 is fixed to the step of the exposure base. A spring clip 404 restricts the position of the liquid crystal cell sample 401 and ensures good contact between the exposed transparent conductive electrode on the other side and the metal conductive contact. The pair of metal conductive contacts are led out to the interface on the exposure base through metal wires, and then electrically connected to the multi-channel voltage signal generator 500 through metal wires with standard interfaces.

[0085] In a preferred embodiment, the exposure apparatus further includes a monitoring module 6, which includes a switchable semi-transparent mirror 600 and a camera, which is a CCD camera or a CMOS camera 601. The switchable semi-transparent mirror 600 is located between the focusing servo module 3 and the sample placement module 4, and is used to switch the optical path between the focusing servo module 3 and the sample placement module 4, and to reflect the light beam reflected by the sample placement module 4 into the camera.

[0086] The switchable semi-transparent and semi-reflective mirror 600 is a mechanically push-pull type semi-transparent and semi-reflective mirror that enables monitoring of the exposure status.

[0087] Example 2

[0088] like Figure 5 As shown, this embodiment is largely the same as embodiment 1, except that this embodiment adopts a light intensity and polarization control module structure of transmissive light intensity modulation structure + reflective polarization modulation structure. The second spatial phase modulator 201 can adopt an LCoS structure or an SLM structure. The first electronically controlled liquid crystal waveplate 204 and the second electronically controlled liquid crystal waveplate 205 are both of the model of electronically tunable QWP@450 / 550nm, which can be set according to specific application requirements and is not limited to one. The first transmissive liquid crystal panel 208 can be a display panel of various modes such as TN, IPS, and VAN.

[0089] Example 3

[0090] like Figure 6 As shown, this embodiment is largely the same as embodiment 1, except that it adopts a light intensity and polarization control module structure of transmissive light intensity modulation structure + transmissive polarization modulation structure. The third electronically controlled liquid crystal waveplate 211 adopts the model of electronically tunable QWP@450 / 550nm, which can be set according to specific application requirements and is not limited to one. The first transmissive liquid crystal panel 208 can be a display panel of various modes such as TN, IPS, and VAN. The second transmissive liquid crystal panel 210 can be a display panel of various modes such as VAN and ECB.

[0091] Example 4

[0092] like Figure 7 As shown, this embodiment is largely the same as embodiment 1, except that this embodiment adopts a light intensity and polarization control module structure of reflective light intensity modulation structure + transmissive polarization modulation structure. The first spatial phase modulator 200 can adopt an LCoS structure or an SLM structure. The third electronically controlled liquid crystal waveplate 211 adopts an electronically tunable QWP@450 / 550nm model, which can be set according to specific application requirements and is not limited to a single model. The second transmissive liquid crystal panel 210 can be an existing VAN, ECB or other mode display panel.

[0093] This invention proposes two different operating modes for an exposure device based on LCoS and liquid crystal devices for experimental teaching and scientific research. Unlike current exposure devices on the market, this invention grants the device more degrees of freedom. Besides being able to manipulate the linear polarization direction of each pixel in the light beam for rapid and efficient pixelated exposure of liquid crystal alignment, it also enables simultaneous multi-grayscale control of the light intensity of each pixel from 0 to 1. The exposure modes of this invention can be flexibly switched, and the exposure process is simple and efficient, meeting various application requirements.

[0094] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. An exposure apparatus based on a spatial phase modulator and a liquid crystal device, comprising a focusing servo module (3), a sample placement module (4), and a voltage control module (5), characterized in that, The exposure device further includes a light source control module (1) and a light intensity and polarization control module (2). The light source control module (1) includes a first switchable mirror (103) and a light source switching component for switching between different color light sources. The light intensity and polarization control module (2) includes: A light intensity modulation component is used to receive the light beam output by the light source control module (1) and modulate the light intensity of each pixel in the light beam; A polarization modulation component is used to modulate the polarization state of each pixel in the beam emitted by the light intensity modulation component; The first switchable mirror (103) is located between the light intensity modulation component and the polarization modulation component, and is used to switch the optical path between the light intensity modulation component and the polarization modulation component. Both the focusing servo module (3) and the sample placement module (4) switch the output optical path facing the polarization modulation component or the reflected optical path facing the first switchable mirror (103) through the motion control component. When the first switchable mirror (103) exits the optical path between the light intensity modulation component and the polarization modulation component, and the focusing servo module (3) and the sample placement module (4) are facing the output optical path of the polarization modulation component, The light beam generated by the light source switching component passes through the light intensity modulation component and the polarization modulation component in sequence, and then enters the focusing servo module (3), thereby independently modulating the light intensity and linear polarization direction of each pixel in the light beam output by the polarization modulation component. When the first switchable mirror (103) enters the optical path between the light intensity modulation component and the polarization modulation component, and the focusing servo module (3) and the sample placement module (4) are aligned with the reflected optical path of the first switchable mirror (103), The light beam generated by the light source switching component enters the focusing servo module (3) after passing through the light intensity modulation component, thereby independently modulating the light intensity of each pixel in the light beam.

2. The exposure apparatus based on a spatial phase modulator and a liquid crystal device according to claim 1, characterized in that, The light intensity modulation component is a reflective light intensity modulation structure or a transmissive light intensity modulation structure; the polarization modulation component is a reflective polarization modulation structure or a transmissive polarization modulation structure.

3. The exposure apparatus based on a spatial phase modulator and a liquid crystal device according to claim 2, characterized in that, The reflective light intensity modulation structure includes a first spatial phase modulator (200) and a first polarization beam splitter (202) arranged in sequence. The light beam generated by the light source switching component passes through the first polarization beam splitter (202), the first spatial phase modulator (200) and the first polarization beam splitter (202) in sequence and then exits in the direction of the polarization modulation component. The transmissive light intensity modulation structure includes a first polarizer (207), a first transmissive liquid crystal panel (208), and a second polarizer (209) arranged in sequence. The light beam generated by the light source switching component passes through the first polarizer (207), the first transmissive liquid crystal panel (208), and the second polarizer (209) in sequence before being emitted in the direction of the polarization modulation component. The reflective polarization modulation structure includes a first electrically controlled liquid crystal waveplate (204), a second polarization beam splitter (203), a second spatial phase modulator (201), and a second electrically controlled liquid crystal waveplate (205). The light beam emitted from the light intensity modulation component passes sequentially through the first electrically controlled liquid crystal waveplate (204), the second polarization beam splitter (203), the second spatial phase modulator (201), the second polarization beam splitter (203), and the second electrically controlled liquid crystal waveplate (205) before being emitted toward the focusing servo module (3). The transmissive polarization modulation structure includes a second transmissive liquid crystal panel (210), a third electronically controlled liquid crystal waveplate (211), and a fixed reflector (212) arranged in sequence. The light beam emitted by the light intensity modulation component passes through the second transmissive liquid crystal panel (210), the third electronically controlled liquid crystal waveplate (211), and the fixed reflector (212) in sequence before being emitted toward the focusing servo module (3).

4. The exposure apparatus based on a spatial phase modulator and a liquid crystal device according to claim 3, characterized in that, The voltage control module (5) includes a multi-channel voltage signal generator (500) and a signal control device. The first electronically controlled liquid crystal waveplate (204), the second electronically controlled liquid crystal waveplate (205), and the third electronically controlled liquid crystal waveplate (211) are all electrically connected to the multi-channel voltage signal generator (500) through metal wires. The first transmissive liquid crystal panel (208), the second transmissive liquid crystal panel (210), the first spatial phase modulator (200), and the second spatial phase modulator (201) are all electrically connected to the signal control device through data lines.

5. The exposure apparatus based on a spatial phase modulator and a liquid crystal device according to claim 1, characterized in that, The light source switching component includes a main light source (100), a secondary light source (101), and a second switchable reflector (102). The wavelength of the main light source (100) is within the range of 300-500 nanometers or 600-1000 nanometers. The light beams of the main light source (100) and the secondary light source (101) have different colors. The main light source (100) is directly opposite the input end of the light intensity modulation component, and the second switchable reflector (102) is directly opposite the secondary light source (101). It is used to switch the light path between the main light source (100) and the light intensity modulation component, thereby switching the main light source (100) and the secondary light source (101).

6. The exposure apparatus based on a spatial phase modulator and a liquid crystal device according to claim 1, characterized in that, The light source switching component includes a white light source and detachable color filters, which are used to switch between different color light sources by inserting different color filters under the white light source.

7. The exposure apparatus based on a spatial phase modulator and a liquid crystal device according to claim 1, characterized in that, The sample placement module (4) includes an adjustment platform (402), a sample exposure base (400), and a liquid crystal cell sample (401). The adjustment platform (402) is provided with a slide rail for the sample exposure base (400) to slide, and the liquid crystal cell sample (401) is mounted on the sample exposure base (400). The liquid crystal cell sample (401) includes an upper substrate, a lower substrate and a liquid crystal cell. Both the upper substrate and the lower substrate are provided with transparent conductive electrodes. At least one of the upper substrate and the lower substrate is coated with a photoalignment layer. The upper substrate and the lower substrate are respectively connected to the two ends of the liquid crystal cell and form a Z-shaped structure. The sample exposure base (400) is provided with a Z-shaped groove. One end of the Z-shaped groove has a step at the bottom and a protrusion at the top of the other side. A first metal conductive contact is provided on the step for contacting the transparent conductive electrode of the upper substrate. The Z-shaped groove is also provided with an elastic buckle (404) located at the top of the step for limiting the position of the liquid crystal cell sample (401). A second metal conductive contact is provided at the bottom of the protrusion for contacting the transparent conductive electrode of the lower substrate. The first and second metal conductive contacts are electrically connected to the voltage control module (5) through metal wires.

8. The exposure apparatus based on a spatial phase modulator and a liquid crystal device according to claim 1, characterized in that, The exposure device also includes a monitoring module (6), which includes a switchable semi-transparent mirror (600) and a camera, the camera being a CCD camera or a CMOS camera (601). The switchable semi-transparent mirror (600) is located between the focusing servo module (3) and the sample placement module (4) and is used to switch the optical path between the focusing servo module (3) and the sample placement module (4) to reflect the light beam reflected by the sample placement module (4) into the camera.

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