Optical device and preparation method thereof, three-dimensional display system and printing system

Abstract

The invention relates to the technical field of display, and particularly discloses an optical device and a preparation method thereof, a three-dimensional display system and a printing system. The preparation method of the optical device comprises the following steps: providing a substrate; forming a light-operated orientation layer on the substrate, wherein the light-operated orientation layer comprises a linear polarization sensitive material; performing exposure orientation on the linear polarization sensitive material in the light-operated orientation layer; and forming a liquid crystal polymer film layer on one side, far away from the substrate, of the photo-alignment layer. The linear polarization sensitive material in the light-operated orientation layer can absorb energy of linearly polarized light and perform orientation on liquid crystal long-axis molecules in the liquid crystal polymer film layer, and the liquid crystal polymer film layer can perform geometric phase modulation on incident light. Therefore, a three-dimensional polarization display effect can be designed according to requirements, and diversified display requirements are met.

Description

Technical Field

[0001] The present application relates to the field of display technologies, and particularly to an optical device, a preparation method thereof, a three-dimensional display system, and a printing system. Background Art

[0002] Most of the existing flat panel displays are two-dimensional planar displays, which can only provide an amplitude information, and viewers cannot obtain depth information such as the occlusion relationship of an object. The light field three-dimensional display technology is a technology that is currently more likely to be commercialized. Specifically, it means that the parallax images displayed in the existing flat panel are respectively projected onto a designed viewing area to form a continuous simulated parallax change of the human eye, making people have the feeling of viewing a three-dimensional object.

[0003] The light field three-dimensional display technology uses a traditional flat panel to load the required parallax images. After the backlight passes through the flat panel and then passes through a phase plate, a series of viewing areas will be arranged on the front. The diffracted light of the traditional relief structure phase plate is polarization-insensitive, so it will diffract all incident light, and only the viewing area can be designed on the front of the display panel. The maximum viewing angle is 180°, and only the front surface of the object can be seen, which cannot meet the current diverse requirements. Summary of the Invention

[0004] Based on this, in view of the above problems, it is necessary to provide an optical device, a preparation method thereof, a three-dimensional display system, and a laser direct writing printing system.

[0005] The present application provides a polarization laser direct writing printing system, including a phase-type spatial light modulator, a quarter-wave plate, a polarization-insensitive reduction objective lens, and a substrate arranged in sequence. A photo-controlled alignment layer is arranged on one side of the substrate close to the polarization-insensitive reduction objective lens.

[0006] The phase-type spatial light modulator is used to receive a pixelated image, and can adjust the phase of incident light pixel by pixel under the drive of voltage and reflect it to the quarter-wave plate. The quarter-wave plate converts the phase delay amount of different pixels into polarization information, and exposes it to the photo-controlled alignment layer through the polarization-insensitive reduction objective lens to align the linearly polarized light-sensitive material in the photo-controlled alignment layer.

[0007] In one embodiment, the polarization laser direct writing printing system further includes a pulsed laser source, a linear polarizer, and a mirror. The pulsed laser source, the linear polarizer, the mirror, and the phase-type spatial light modulator are arranged in sequence.

[0008] The laser emitted by the pulsed laser source is converted into linearly polarized light by the linear polarizer, and the linearly polarized light is reflected by the mirror to the phase-type spatial light modulator.

[0009] In one embodiment, a half mirror is further disposed between the quarter-wave plate and the polarization-independent reduction objective lens.

[0010] In one embodiment, the polarization laser direct writing printing system further includes a controller, which is electrically connected to the pulsed laser source, the phase-type spatial light modulator, and the substrate respectively, and is used for regulating the pulsed laser source, refreshing the pixelated image received by the phase-type spatial light modulator, and acquiring the polarization information in the photo-controlled alignment layer.

[0011] In one embodiment, the polarization laser direct writing printing system further includes an autofocus optical path, and the output light of the autofocus optical path is emitted to the half mirror, and is used for adjusting the distance between the polarization-independent reduction objective lens and the photo-controlled alignment layer.

[0012] According to the first aspect of the embodiments of the present application, a method for preparing an optical device is provided, including:

[0013] Providing a substrate;

[0014] Forming a photo-controlled alignment layer on the substrate, where the photo-controlled alignment layer includes a linearly polarization-sensitive material;

[0015] Performing exposure alignment on the linearly polarization-sensitive material in the photo-controlled alignment layer;

[0016] Forming a liquid crystal polymer thin film layer on a side of the photo-controlled alignment layer away from the substrate.

[0017] In one embodiment, the step of forming a liquid crystal polymer thin film layer on a side of the photo-controlled alignment layer away from the substrate includes:

[0018] Forming a nematic liquid crystal polymer layer on a side of the photo-controlled alignment layer away from the substrate;

[0019] Or, forming a cholesteric liquid crystal polymer layer on a side of the photo-controlled alignment layer away from the substrate;

[0020] Or, forming a nematic liquid crystal polymer layer on a side of the photo-controlled alignment layer away from the substrate, and forming a cholesteric liquid crystal polymer layer on a side of the nematic liquid crystal polymer layer away from the photo-controlled alignment layer.

[0021] According to the second aspect of the embodiments of the present application, an optical device is provided, and the optical device is prepared by the above method for preparing an optical device.

[0022] According to a third aspect of the embodiments of the present application, a three-dimensional display system is provided, which includes a projector and the optical device as described above; the projector is arranged on one side facing the liquid crystal polymer thin film layer in the optical device, and is used to project light onto the liquid crystal polymer thin film layer to form an observation window on at least one side of the optical device. The observation window has multiple observation areas, and different observation areas correspond to images of different perspectives of the three-dimensional diagram.

[0023] In one embodiment, the liquid crystal polymer thin film layer includes a nematic liquid crystal polymer layer, and the projected light of the projector forms the observation window on the side facing the substrate after passing through the optical device.

[0024] In one embodiment, the liquid crystal polymer thin film layer includes a cholesteric liquid crystal polymer layer, and the projected light of the projector forms the observation window on the side facing the cholesteric liquid crystal polymer layer after being reflected by the optical device.

[0025] In one embodiment, the liquid crystal polymer thin film layer includes a stacked nematic liquid crystal polymer layer and a cholesteric liquid crystal polymer layer. The cholesteric liquid crystal polymer layer is located on the side of the nematic liquid crystal polymer layer away from the substrate. The projected light of the projector forms the observation window on the side facing the substrate after passing through the optical device and on the side facing the cholesteric liquid crystal polymer layer after being reflected by the optical device.

[0026] The preparation method of the optical device provided by the embodiments of the present application is as follows: First, a photo-controlled alignment layer is formed on the substrate. The photo-controlled alignment layer includes a linearly polarized light-sensitive material. Then, the linearly polarized light-sensitive material in the photo-controlled alignment layer is exposed and aligned. Finally, a liquid crystal polymer thin film layer is formed on the side of the photo-controlled alignment layer away from the substrate. The linearly polarized light-sensitive material in the photo-controlled alignment layer can absorb the energy of linearly polarized light and align the liquid crystal long-axis molecules in the liquid crystal polymer thin film layer. The liquid crystal polymer thin film layer can perform geometric phase modulation on the incident light, and thus a three-dimensional polarization display effect can be designed according to requirements to achieve diversified display requirements. Description of the Drawings

[0027] Figure 1 It is a schematic structural diagram of an optical device provided by an embodiment of the present application;

[0028] Figure 2 It is a schematic structural diagram of an optical device provided by an embodiment of the present application;

[0029] Figure 3 It is a schematic structural diagram of an optical device provided by an embodiment of the present application;

[0030] Figure 4Schematic structural diagram of an optical device provided by an embodiment of the present application;

[0031] Figure 5 Flow block diagram of a preparation method of an optical device provided by an embodiment of the present application;

[0032] Figure 6 Schematic structural diagram of a 3D display system provided by an embodiment of the present application;

[0033] Figure 7 Schematic structural diagram of a 3D display system provided by an embodiment of the present application;

[0034] Figure 8 Schematic structural diagram of a 3D display system provided by an embodiment of the present application;

[0035] Figure 9 Schematic structural diagram of a polarization laser direct writing printing system provided by an embodiment of the present application;

[0036] Figure 10 Schematic structural diagram of a polarization laser direct writing printing system provided by an embodiment of the present application.

[0037] Explanation of reference numerals:

[0038] 110, substrate; 120, optically controlled alignment layer; 130, liquid crystal polymer thin film layer; 131, nematic liquid crystal polymer layer; 132, cholesteric liquid crystal polymer layer; 200, projector; 210, projection light; 300, observation window; 310, observation area; 410, pixelated image; 420, phase-type spatial light modulator; 430, quarter-wave plate; 440, polarization-independent reduction objective lens; 460, translation stage; 510, pulsed laser source; 520, linear polarizer; 530, mirror; 540, beam splitter; 550, controller; 560, control computer; 570, autofocus optical path; 580, real-time detection optical path; 590, tube lens. Detailed implementation manners

[0039] To facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0040] In this application, unless otherwise clearly specified and defined, terms such as "installation", "connection", "linkage", "fixation" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0041] The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the description of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0043] This application provides an optical device, a preparation method thereof, a three-dimensional display system, and a laser direct writing and printing system.

[0044] In one embodiment, referring to Figures 1-4 , an optical device is provided, which includes a substrate 110, a photo-controlled alignment layer 120, and a liquid crystal polymer thin film layer 130 that are sequentially stacked; the photo-controlled alignment layer 120 includes a linearly polarized light sensitive material, and the linearly polarized light sensitive material can absorb the energy of linearly polarized light and align the liquid crystal long axis molecules in the liquid crystal polymer thin film layer 130, and the liquid crystal polymer thin film layer 130 can perform geometric phase modulation on incident light.

[0045] Among them, the substrate 110 can be selected as a glass substrate, and the surface of the glass substrate can have hydrophilicity and an optical surface with high transmittance. During the actual preparation process, the substrate 110 can be subjected to a repeated <acetone cleaning - alcohol cleaning - glass cleaning agent cleaning - water cleaning> cleaning process, and then the surface can be bombarded by a plasma cleaner to achieve the purpose of cleaning and modification.

[0046] In this embodiment, the linearly polarized light sensitive material in the photo-controlled alignment layer 120 can include azo dyes, which can absorb the energy of linearly polarized light and align the liquid crystal long axis molecules in the liquid crystal polymer thin film layer 130.

[0047] In the actual preparation process, an azo dye can be spin-coated on one side of the substrate 110 to form a photo-controlled alignment layer 120. Then, the substrate 110 spin-coated with the azo dye is placed in a laser direct writing printing optical system with a patterned linearly polarized light field for exposure alignment. The specific structure of the laser direct writing printing optical system and the principle of exposure alignment can be referred to the specific description of the laser direct writing printing system provided in the subsequent embodiments.

[0048] After the azo dye is aligned in the linearly polarized light field and the exposure alignment is completed, a liquid crystal polymer can be spin-coated on the side of the photo-controlled alignment layer 120 away from the substrate 110 to form a liquid crystal polymer layer. The azo dye can provide anchoring energy to align the liquid crystal molecules in the liquid crystal polymer layer.

[0049] In one embodiment, the liquid crystal polymer thin film layer 130 includes a nematic liquid crystal polymer layer 131 and / or a cholesteric liquid crystal polymer layer 132, and the cholesteric liquid crystal polymer layer 132 includes a mixture of a nematic liquid crystal polymer and a chiral molecular material.

[0050] Specifically, referring to Figure 2 , the liquid crystal polymer thin film layer 130 may only include the nematic liquid crystal polymer layer 131; referring to Figure 3 , the liquid crystal polymer thin film layer 130 may also only include the cholesteric liquid crystal polymer layer 132; referring to Figure 4 , the liquid crystal polymer thin film layer 130 may also include both the nematic liquid crystal polymer layer 131 and the cholesteric liquid crystal polymer layer 132. Among them, the nematic liquid crystal polymer is an anisotropic material with a large birefringence, and geometric phase modulation can be achieved by adjusting the phase difference between the S-wave and P-wave of the incident light.

[0051] The patterned-aligned nematic liquid crystal polymer is a polarization-sensitive structure, which has positive and negative first-order diffractions for chiral polarized light with different rotation directions. When the incident light is controlled to be polarized light with a single rotation direction, single-order transmission diffraction can be achieved, improving the light energy utilization rate.

[0052] The cholesteric liquid crystal polymer is a mixture of a nematic liquid crystal polymer and a chiral molecular material, that is, a chiral agent is added to the nematic liquid crystal polymer to achieve a helical twist of the long axis molecules of the liquid crystal perpendicular to the surface. The pitch can be accurately adjusted by adjusting the concentration of the chiral agent, thereby controlling the band range of the reflected diffracted light, and left-handed or right-handed polarized light can be selectively reflected by selecting the chirality of the chiral agent.

[0053] The patterned cholesteric liquid crystal polymer is a polarization-sensitive structure. For chiral polarized light with different helicities, there are two states: Bragg reflection diffraction and transparency respectively. When the helicity of the incident polarized light is controlled to be consistent with that of the cholesteric liquid crystal, Bragg reflection diffraction can be achieved at a specific wavelength and a specific incident angle. At the same time, the incident light with the orthogonal helicity will directly pass through the cholesteric liquid crystal polymer.

[0054] When the liquid crystal polymer layer includes a nematic liquid crystal polymer layer 131 and a cholesteric liquid crystal polymer layer 132 at the same time, the nematic liquid crystal polymer layer 131 and the cholesteric liquid crystal polymer layer 132 can be stacked in sequence on the side of the photo-alignment layer 120 away from the substrate 110.

[0055] In the above optical device provided in this embodiment, a photo-alignment layer 120 and a liquid crystal polymer thin film layer 130 are stacked on the substrate 110. The liquid crystal polymer thin film layer 130 can perform geometric phase modulation on the incident light. The linearly polarized light-sensitive material in the photo-alignment layer 120 can absorb the energy of the linearly polarized light and orient the liquid crystal long axis molecules in the liquid crystal polymer thin film layer 130. Furthermore, a three-dimensional polarization display effect can be designed according to requirements to meet diverse display needs.

[0056] In one embodiment, a preparation method of an optical device is provided. Through this preparation method, the optical device provided in the foregoing embodiment can be prepared.

[0057] Refer to Figure 5 , the preparation method of the optical device provided in this embodiment includes the following steps:

[0058] Step S100, provide the substrate 110.

[0059] The substrate 110 can be a glass substrate. The glass substrate is repeatedly cleaned by the cleaning process of <acetone cleaning - alcohol cleaning - glass cleaner cleaning - water cleaning> to remove impurities on the surface of the glass substrate and enhance the hydrophilic property of the substrate 110. Finally, it is ensured that the surface of the glass substrate has hydrophilicity and high transmittance.

[0060] Step S300, form the photo-alignment layer 120 on the substrate 110, and the photo-alignment layer 120 includes a linearly polarized light-sensitive material.

[0061] The linearly polarized light-sensitive material in the photo-alignment layer 120 can specifically be an azo dye. Specifically, the azo dye can be spin-coated on one side surface of the substrate 110 and wait for the solvent to fully volatilize.

[0062] Step S500, perform exposure alignment on the linearly polarized light-sensitive material in the photo-alignment layer 120.

[0063] After the photo-controlled alignment layer 120 is formed, the linearly polarized sensitive material in the photo-controlled alignment layer 120 can be exposed and aligned so that it can align the liquid crystal long axis molecules in the subsequently formed liquid crystal polymer thin film layer 130.

[0064] Specifically, step S500 may specifically include: applying a voltage to the phase-type spatial light modulator 420, adjusting the phase of the incident light for each pixel in the pixelated image 410 in the phase-type spatial light modulator 420 and reflecting it to the quarter-wave plate 430, converting the phase delay amounts of different pixels into polarization information through the quarter-wave plate 430, and then exposing the photo-controlled alignment layer 120 through the polarization-insensitive reduction objective lens 440 to align the linearly polarized sensitive material in the photo-controlled alignment layer 120.

[0065] That is, the substrate 110 coated with the photo-controlled alignment layer 120 can be placed in a pre-formed polarization laser direct writing printing optical system, which includes a phase-type spatial light modulator 420, a quarter-wave plate 430, and a polarization-insensitive reduction objective lens 440. Among them, the phase-type spatial light modulator 420 is placed in a linearly polarized light field. By applying a voltage, the phase-type spatial light modulator 420 can adjust the phase of the incident light pixel by pixel and reflect it. The reflected light becomes a pixelated polarized light field after passing through the quarter-wave plate 430, that is, the phase delay information is converted into polarization information, and then it is exposed to the glass substrate 110 coated with the azo dye photo-controlled alignment layer through the polarization-insensitive reduction objective lens 440, thereby realizing the alignment of azo dye molecules.

[0066] Among them, the pixelated images 410 with different gray levels loaded on the phase-type spatial light modulator 420 correspond to different phase delay amounts. The 0-255 gray level range includes a phase control range greater than 2π, which can satisfy the polarization direction control of 0-180°, and the control accuracy is less than 1°.

[0067] Step S700: Form a liquid crystal polymer thin film layer 130 on the side of the photo-controlled alignment layer 120 away from the substrate 110.

[0068] When the azo dye in the photo-controlled alignment layer 120 is exposed and aligned, a liquid crystal polymer thin film layer 130 can be formed on the side of the photo-controlled alignment layer 120 away from the substrate 110. Specifically, the liquid crystal polymer can be spin-coated on the surface of the side of the photo-controlled alignment layer 120 away from the substrate 110. In practical applications, the azo dye will provide anchoring energy to align the liquid crystal molecules, and then it is cured by a UV lamp to form a film, forming the liquid crystal polymer thin film layer 130.

[0069] Among them, the liquid crystal polymer thin film layer 130 may only include a nematic liquid crystal polymer layer 131, that is, it is only necessary to form a nematic liquid crystal polymer layer 131 on the side of the photo-alignment layer 120 away from the substrate 110. At this time, the optical device is a transmissive optical device.

[0070] The liquid crystal polymer thin film layer 130 may only include a cholesteric liquid crystal polymer layer 132, that is, it is only necessary to form a cholesteric liquid crystal polymer layer 132 on the side of the photo-alignment layer 120 away from the substrate 110. At this time, the optical device is a reflective optical device.

[0071] The liquid crystal polymer thin film layer 130 may simultaneously include a nematic liquid crystal polymer layer 131 and a cholesteric liquid crystal polymer layer 132. Then, a nematic liquid crystal polymer layer 131 and a cholesteric liquid crystal polymer layer 132 may be sequentially formed on the side of the photo-alignment layer 120 away from the substrate 110. Among them, the cholesteric liquid crystal polymer layer 132 is located on the side of the nematic liquid crystal polymer layer 131 away from the photo-alignment layer 120. At this time, the optical device is a transmissive-reflective dual-sided display optical device.

[0072] To meet the half-wave condition, the above-mentioned spin-coating and curing steps of the nematic liquid crystal polymer may be repeated until the film thickness d meets certain requirements. For example, the film thickness d satisfies Δnd = λ / 2, where Δn is the birefringence of the liquid crystal polymer material and λ is the wavelength of the incident light. To achieve a sufficient film thickness to generate efficient Bragg reflection diffraction, the above-mentioned spin-coating and curing steps of the cholesteric liquid crystal polymer may be repeated.

[0073] In one embodiment, referring to Figures 6-8 , a three-dimensional display system is provided, including a projector 200, an observation window 300, and the optical device described in the foregoing embodiment; the projector 200 is disposed facing the side of the liquid crystal polymer thin film layer 130 in the optical device, and is configured to project light onto the liquid crystal polymer thin film layer 130 to form an observation window in at least one side direction of the optical device. The observation window 300 has a plurality of observation regions 310. After the light projected by the projector irradiates on the glass substrate coated with the liquid crystal polymer thin film layer 130, the reflected light or transmitted light can form an observation window 300 at a certain distance from the substrate. The observation window 300 has a plurality of dot-shaped observation regions 310, and different observation regions 310 correspond to images of different perspectives of the three-dimensional map. For the specific structure of the optical device, reference may be made to the specific description of the optical device provided in the foregoing embodiment, which will not be elaborated herein.

[0074] In this embodiment, the projection area of the projector 200 is aligned with the area where the substrate 110 is located, and the projector 200 adopts an inclined lighting projection method.

[0075] The optical device includes opposite sides, namely the side of the substrate 110 and the side of the liquid crystal polymer thin film layer 130 respectively. The observation window 300 can be formed on the side of the substrate 110, or on the side of the liquid crystal polymer thin film layer 130, or can be formed on both the side of the substrate 110 and the side of the liquid crystal polymer thin film layer 130 simultaneously.

[0076] Taking the case where the observation window 300 is formed on the side of the substrate 110 as an example, the observation window 300 can be facing the substrate 110 and maintain a certain distance from the substrate 110. The observation window 300 has a plurality of dot-shaped observation areas 310, and different observation areas 310 correspond to images of different perspectives of the 3D map. The light rays representing the image information of the same observation perspective in the 3D image enter the same observation area 310.

[0077] In one embodiment, the liquid crystal polymer thin film layer 130 includes a nematic liquid crystal polymer layer 131, and the projection light of the projector 200 forms the observation window 300 on the side facing the substrate 110 after being transmitted through the optical device.

[0078] Refer to Figure 6 , when the liquid crystal polymer thin film layer 130 is the nematic liquid crystal polymer layer 131, when the light projected by the projector 200 irradiates on the nematic liquid crystal polymer layer 131, transmission diffraction can occur after passing through the nematic liquid crystal polymer layer 131 and the substrate 110, and the diffracted light rays can form the observation window 300 on the side facing the substrate 110. The diffracted light rays representing the image information of the same observation perspective in the 3D image enter the same observation area 310 in the observation window 300. The orientation structure of the nematic liquid crystal polymer is jointly determined by the incident angle of the projection light 210 of the projector 200, the exit angle of the transmitted diffracted light rays, and the diffraction wavelength.

[0079] In one embodiment, the liquid crystal polymer thin film layer 130 includes a cholesteric liquid crystal polymer layer 132, and the projection light of the projector 200 forms the observation window 300 on the side facing the cholesteric liquid crystal polymer layer 132 after being reflected by the optical device.

[0080] Refer to Figure 7 , when the liquid crystal polymer thin film layer 130 is the cholesteric liquid crystal polymer layer 132, when the light projected by the projector 200 irradiates on the cholesteric liquid crystal polymer layer 132, Bragg reflection diffraction occurs in the cholesteric liquid crystal polymer layer 132, and the reflected light rays can form the observation window 300 on the side facing the cholesteric liquid crystal polymer layer 132. The diffracted light rays representing the image information of the same observation perspective in the 3D image enter the same observation area 310 in the observation window 300. The orientation structure of the cholesteric liquid crystal polymer is jointly determined by the incident angle of the projection light 210 of the projector 200, the exit angle of the Bragg reflection diffracted light rays, and the diffraction wavelength.

[0081] In one embodiment, the liquid crystal polymer thin film layer 130 includes a stacked nematic liquid crystal polymer layer 131 and a cholesteric liquid crystal polymer layer 132. The cholesteric liquid crystal polymer layer 132 is located on the side of the nematic liquid crystal polymer layer 131 away from the substrate 110. The projection light of the projector 200 forms the observation window 300 on both the side facing the substrate 110 after passing through the optical device and on the side facing the cholesteric liquid crystal polymer layer 132 after being reflected by the optical device.

[0082] Referring to Figure 8 , when the liquid crystal polymer thin film layer 130 includes a stacked nematic liquid crystal polymer layer 131 and a cholesteric liquid crystal polymer layer 132, when the light projected by the projector 200 irradiates the substrate 110 coated with nematic liquid crystal polymer and cholesteric liquid crystal polymer on the surface, the polarized light with the same polarization rotation direction as the chiral meter rotation direction of the cholesteric liquid crystal polymer will undergo Bragg reflection diffraction, while the circularly polarized light with the orthogonal rotation direction will pass through the cholesteric liquid crystal polymer layer 132 and enter the nematic liquid crystal polymer layer 131, and then undergo transmission diffraction. Thus, the observation window 300 can be formed on both sides, and images can be observed on both sides, realizing double-sided three-dimensional polarization display.

[0083] Compared with the planar display that can only see the information on one side of 180°, the double-sided display can see the information on the back side greater than 180°, giving people a more immersive 3D feeling; the double-sided display of the present application can cooperate with the projection to achieve dynamic refresh, realize human-computer interaction, and is conducive to being popularized in various fields such as advertising signs, entertainment, military, and medical. In addition, the present application introduces polarization parameters, which can have twice the bandwidth, and can be freely designed to display only one side or the same or different information on both sides.

[0084] Referring to Figure 9 , in one embodiment, a polarization laser direct writing and printing system is provided, including a phase-type spatial light modulator 420, a quarter-wave plate 430, a polarization-independent reduction objective lens 440, and a substrate 110 arranged in sequence. A photo-controlled alignment layer 120 is provided on the side of the substrate 110 close to the polarization-independent reduction objective lens 440. The phase-type spatial light modulator 420 is used to receive the pixelated image 410, and can adjust the phase of the incident light pixel by pixel under the drive of voltage and reflect it to the quarter-wave plate 430. The quarter-wave plate 430 converts the phase delay amount of different pixels into polarization information, and exposes the photo-controlled alignment layer 120 through the polarization-independent reduction objective lens 440 to align the linearly polarized light-sensitive material in the photo-controlled alignment layer 120.

[0085] In practical applications, the phase-type spatial light modulator 420 can be placed in a linearly polarized light field. The phase-type spatial light modulator 420 can adjust the phase of the incident light pixel by pixel under the drive of voltage and reflect it. The reflected light becomes a pixelated polarized light field after passing through a quarter-wave plate. The derivation using the Jones matrix formula is as follows:

[0086] The incident light is represented by the Jones matrix as:

[0087]

[0088] After passing through a polarizer with a polarization direction in the X direction, the polarization state of the light wave becomes:

[0089]

[0090] After this polarized light passes through a general wave plate with an optical axis at 45° to the optical axis of the polarizer, the polarization state changes to:

[0091]

[0092] where δ is the phase delay of the general wave plate. After passing through a quarter-wave plate with a fast axis at 45° to the optical axis of the polarizer:

[0093]

[0094] Discarding the amplitude information E xin , it can be obtained that the polarized light rotates clockwise from the original by to become Similarly, when the polarization direction of the linear polarizer 520 is the Y axis, after passing through the general wave plate and the quarter-wave plate respectively, the polarization direction rotates counterclockwise by Therefore, regardless of the direction of the polarizer, the rotation of the polarization direction of the polarized light can be achieved by controlling the phase delay of the general wave plate. The phase-type spatial light modulator is a special wave plate. As an array-type phase modulation device, it can output a patterned linearly polarized light field by adjusting the phase pixel by pixel.

[0095] By loading images with different grayscales on the phase-type spatial light modulator 420 to control the phase delay in different pixels, after passing through the quarter-wave plate, the phase delay information is converted into polarization information, and after being magnified and exposed through a polarization-insensitive objective lens onto the glass substrate 110 coated with azo dyes, the orientation of azo dye molecules can be achieved.

[0096] The pixelated images 410 with different grayscales loaded on the phase-type spatial light modulator 420 correspond to different phase delays. The 0-255 grayscale includes a phase modulation range greater than 2π, which can satisfy the polarization direction control of 0-180°, and the control accuracy is less than 1°.

[0097] In one embodiment, referring to Figure 10 , the polarization laser direct writing and printing system provided in this embodiment further includes a pulsed laser source 510, a linear polarizer 520, and a mirror 530. The pulsed laser source 510, the linear polarizer 520, the mirror 530, and the phase-type spatial light modulator 420 are arranged in sequence.

[0098] The laser emitted by the pulsed laser source 510 is converted into linearly polarized light by the linear polarizer 520, and the linearly polarized light is reflected by the mirror 530 to the phase-type spatial light modulator 420.

[0099] In one embodiment, referring to Figure 10 , a beam splitter 540 is further disposed between the quarter-wave plate 430 and the polarization-insensitive reduction objective 440.

[0100] That is, after the phase-type spatial light modulator 420 performs phase modulation on the incident light, it is reflected to the quarter-wave plate 430. The outgoing light is a patterned linearly polarized distribution. After passing through the beam splitter 540, it is then exposed to the surface of the sample by the polarization-insensitive reduction objective 440.

[0101] In one embodiment, referring to Figure 10 , the polarization laser direct writing and printing system provided in this embodiment further includes a controller 550. The controller 550 is electrically connected to the pulsed laser source 510, the phase-type spatial light modulator 420, and the substrate 110 respectively, and is used for controlling the pulsed laser source 510, refreshing the pixelated image 410 received by the phase-type spatial light modulator 420, and obtaining the polarization information in the optically controlled alignment layer 120.

[0102] The controller 550 can be connected to a control computer 560, and under the program control set by the control computer 560, it can control the pulse timing of the laser emitted by the pulsed laser source 510. At the same time, it can also refresh the pattern of the phase-type spatial light modulator 420 and record the large-area stitching of the patterned linearly polarized information on the optically controlled alignment layer 120 on the substrate 110.

[0103] In one embodiment, referring to Figure 10 , the polarization laser direct writing and printing system provided in this embodiment further includes an autofocus optical path 570. The output light of the autofocus optical path 570 is emitted to the beam splitter 540, and is used to adjust the distance between the polarization-insensitive reduction objective 440 and the optically controlled alignment layer 120, so as to ensure the accurate recording of the pattern linearly polarized light field information.

[0104] In addition, referring to Figure 10, the laser direct writing printing system provided in this embodiment further includes a real-time detection optical path 580, and the real-time detection optical path 580 can record the imaging process on the surface of the photo-controlled alignment layer 120 in real time.

[0105] In this embodiment, referring to Figure 10 , a tube lens 590 is further provided between the quarter-wave plate 430 and the semi-transmissive and semi-reflective mirror 540. The substrate 110 is disposed on the translation stage 460, and the substrate 110 can be translated through the translation stage 460, and the translation stage 460 can be a two-dimensional precision translation stage 460.

[0106] In this embodiment, the pulsed laser source 510 can adopt a solid-state laser light source, such as a nanosecond pulsed laser light source, etc. Its output frequency can reach more than 1000 Hz, and the pulsed energy is high, and it can generate an instantaneous polarized light field for photo-orientation of the photo-orientation material (i.e., azo dye).

[0107] Compared with other non-polarized printing systems, the polarized laser direct writing printing system of the present application introduces a polarization parameter, which can have one more dimension. At the same time, it is for the orientation of polarization-sensitive materials, and there is no need for a developing step later, and ultra-thin film devices can be prepared; compared with other polarization exposure systems, the present application adopts LCoS, which can expose multi-gray-scale and multi-orientation patterns simultaneously, and the speed is greatly improved compared with DMD; compared with optical path exposure, the present application can freely design patterns and perform large-format splicing.

[0108] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0109] The above-described embodiments only represent several implementation manners of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A polarization laser direct writing printing system, characterized in that, it includes a phase-type spatial light modulator, a quarter-wave plate, a polarization-independent reduction objective lens, and a substrate arranged in sequence. A photo-controlled alignment layer is provided on one side of the substrate close to the polarization-independent reduction objective lens; the phase-type spatial light modulator is used to receive a pixelated image, and can adjust the phase of incident light pixel by pixel under the drive of voltage and reflect it to the quarter-wave plate. The quarter-wave plate converts the phase delay amounts of different pixels into polarization information, and exposes it to the photo-controlled alignment layer through the polarization-independent reduction objective lens to align the linearly polarized sensitive material in the photo-controlled alignment layer.

2. The polarization laser direct writing printing system according to claim 1, characterized in that, the laser direct writing printing system further includes a pulsed laser source, a linear polarizer, and a mirror. The pulsed laser source, the linear polarizer, the mirror, and the phase-type spatial light modulator are arranged in sequence; the laser emitted by the pulsed laser source is converted into linearly polarized light by the linear polarizer, and the linearly polarized light is reflected by the mirror to the phase-type spatial light modulator.

3. The polarization laser direct writing printing system according to claim 1, characterized in that, a half-transmissive and half-reflective mirror is further provided between the quarter-wave plate and the polarization-independent reduction objective lens.

4. The polarization laser direct writing printing system according to claim 2, characterized in that, the laser direct writing printing system further includes a controller, and the controller is electrically connected to the pulsed laser source, the phase-type spatial light modulator, and the substrate respectively, and is used to control the pulsed laser source, refresh the pixelated image received by the phase-type spatial light modulator, and obtain the polarization information in the photo-controlled alignment layer.

5. The polarization laser direct writing printing system according to claim 3, characterized in that, the laser direct writing printing system further includes an autofocus optical path, and the output light of the autofocus optical path is emitted to the half-transmissive and half-reflective mirror, and is used to adjust the distance between the polarization-independent reduction objective lens and the photo-controlled alignment layer.

6. A method for preparing an optical device, characterized in that, it includes: providing a substrate; forming a photo-controlled alignment layer on the substrate, and the photo-controlled alignment layer includes a linearly polarized sensitive material; exposing and aligning the linearly polarized sensitive material in the photo-controlled alignment layer in the polarization laser direct writing printing system according to any one of claims 1-5; forming a liquid crystal polymer thin film layer on the side of the photo-controlled alignment layer away from the substrate.

7. The method for preparing an optical device according to claim 6, characterized in that, the step of forming a liquid crystal polymer thin film layer on the side of the photo-controlled alignment layer away from the substrate includes: forming a nematic liquid crystal polymer layer on the side of the photo-controlled alignment layer away from the substrate; or, forming a cholesteric liquid crystal polymer layer on the side of the photo-controlled alignment layer away from the substrate; or, forming a nematic liquid crystal polymer layer on the side of the photo-controlled alignment layer away from the substrate, and forming a cholesteric liquid crystal polymer layer on the side of the nematic liquid crystal polymer layer away from the photo-controlled alignment layer.

8. An optical device, It is characterized in that the optical device is prepared by the preparation method of the optical device as described in claim 6.

9. A three-dimensional display system It is characterized in that it includes a projector and the optical device as described in claim 8; The projector is arranged on one side facing the liquid crystal polymer thin film layer in the optical device, and is used to project light onto the liquid crystal polymer thin film layer to form an observation window in at least one side direction of the optical device. The observation window has a plurality of observation areas, and different observation areas correspond to images of different perspectives of the three-dimensional image.

10. The three-dimensional display system according to claim 9 It is characterized in that the liquid crystal polymer thin film layer includes a nematic liquid crystal polymer layer, and the projection light of the projector forms the observation window on the side facing the substrate after passing through the optical device.

11. The three-dimensional display system according to claim 9 It is characterized in that the liquid crystal polymer thin film layer includes a cholesteric liquid crystal polymer layer, and the projection light of the projector forms the observation window on the side facing the cholesteric liquid crystal polymer layer after being reflected by the optical device.

12. The three-dimensional display system according to claim 9 It is characterized in that the liquid crystal polymer thin film layer includes a stacked nematic liquid crystal polymer layer and a cholesteric liquid crystal polymer layer. The cholesteric liquid crystal polymer layer is located on the side of the nematic liquid crystal polymer layer away from the substrate. The projection light of the projector forms the observation window on the side facing the substrate after passing through the optical device and on the side facing the cholesteric liquid crystal polymer layer after being reflected by the optical device.

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