A method for eliminating liquid crystal disclination lines

Abstract

The present invention discloses a method for eliminating liquid crystal disclination lines, which relates to the technical field of liquid crystals. The method includes the following steps: preparing a reconfigurable chiral liquid crystal system; building an optical system for eliminating disclination lines of a liquid crystal doped with a photo-isomerizable material; starting a de-twisting light source to emit de-twisting light, and making the de-twisting light perpendicularly irradiate on a single reconfigurable chiral liquid crystal sheet or a reconfigurable chiral liquid crystal cell; starting a restoring light source to emit restoring light, and adjusting the optical path through a beam splitter to make the restoring light perpendicularly irradiate on the single reconfigurable chiral liquid crystal sheet or the reconfigurable chiral liquid crystal cell. The advantages of the present invention are as follows: it provides a method for eliminating liquid crystal disclination lines, which has relatively simple and highly controllable processes compared with the prior art means, does not require long-term standing, can quickly eliminate the disclination lines of a liquid crystal doped with a photo-isomerizable material, can effectively improve the preparation efficiency and preparation yield of liquid crystal optical elements, and has good application prospects in the field of preparation of liquid crystal optical elements.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid crystals, and particularly relates to a method for eliminating disclination lines of liquid crystals. Background Art

[0002] Liquid crystal photonics materials and devices play an increasingly important role in new display technologies and new photonics devices. At present, light-responsive liquid crystal photonics devices have broad application prospects in optical display, optical fiber communication, optical computing, and information processing due to their low energy consumption, low cost, and high quality. Disclination lines are generated when liquid crystals are poured into a liquid crystal cell or spin-coated on a single chip, which is caused by the spatial misalignment of liquid crystal molecules. Disclination lines not only reduce the optical performance of liquid crystal optical elements, but also require more time to obtain a liquid crystal alignment structure that meets expectations. Therefore, reducing and eliminating disclination lines of liquid crystals is very important for the application of liquid crystals.

[0003] Currently, traditional methods for eliminating disclination lines of liquid crystals doped with photo-isomerizable materials include applying an in-plane electric field and long-term static placement, etc. These methods have complex processes, low controllability, and require long-term static placement. Therefore, a simple and rapid method for eliminating disclination lines of liquid crystals doped with photo-isomerizable materials is needed. Summary of the Invention

[0004] The purpose of the present invention is to address the existing problems and provide a method for eliminating disclination lines of liquid crystals, which solves the technical problems in the background art that traditional methods for eliminating disclination lines of liquid crystals doped with photo-isomerizable materials include applying an in-plane electric field and long-term static placement, etc., and these methods have complex processes, low controllability, and require long-term static placement.

[0005] The present invention is achieved through the following technical solutions: A method for eliminating disclination lines of liquid crystals includes the following steps:

[0006] Prepare a reconfigurable chiral liquid crystal system, where the reconfigurable chiral liquid crystal system includes reconfigurable chiral liquid crystals on a single chip and reconfigurable chiral liquid crystals in a liquid crystal cell;

[0007] Build an optical system for eliminating disclination lines of liquid crystals doped with photo-isomerizable materials, where the optical system for eliminating disclination lines of liquid crystals doped with photo-isomerizable materials includes a de-twisting light source, a restoring light source, and a beam splitter;

[0008] Start the de-twisting light source to emit de-twisting light, and make the de-twisting light perpendicularly irradiate on the reconfigurable chiral liquid crystal single chip or the reconfigurable chiral liquid crystal cell;

[0009] Start the restoring light source to emit restoring light, and adjust the optical path through the beam splitter to make the restoring light perpendicularly irradiate on the reconfigurable chiral liquid crystal single chip or the reconfigurable chiral liquid crystal cell.

[0010] Preferably, the preparation process of the reconfigurable chiral liquid crystal single chip is as follows:

[0011] Substrate pretreatment: The substrate is ultrasonically cleaned with ITO cleaning solution for 30 minutes, then ultrasonically cleaned with ultrapure water twice repeatedly, each cleaning time is 10 minutes. The cleaned substrate is put into a drying oven, the temperature of the drying oven is 120 °C, and the drying duration is 40 minutes. Finally, the substrate is subjected to ultraviolet ozone cleaning for 30 minutes;

[0012] Alignment layer preparation: The alignment layer material is spin-coated on the substrate, and the molecules in the alignment layer are arranged to point parallel to the direction in the alignment layer plane;

[0013] Single-piece liquid crystal layer preparation: The reconfigurable chiral liquid crystal material is spin-coated on the alignment layer. Under the combined action of the alignment layer and air, the liquid crystal layer molecules will self-assemble to form a multi-level chiral structure with symmetry breaking.

[0014] Preferably, the alignment layer preparation specifically includes the following steps:

[0015] Spin-coat the alignment layer material on the substrate at a speed of 800 revolutions per minute for 5 seconds;

[0016] Then spin-coat the alignment layer material on the substrate at a speed of 3000 revolutions per minute for 40 seconds;

[0017] After spin-coating the alignment agent, the substrate spin-coated with the alignment layer material is annealed, the annealing temperature is 100 °C, and the annealing time is 10 minutes;

[0018] Use 405 nm linearly polarized light to uniformly orient the alignment layer.

[0019] Preferably, the single-piece liquid crystal layer preparation specifically includes the following steps:

[0020] Heat the reconfigurable chiral liquid crystal material to 70 °C, and then spin-coat the reconfigurable chiral liquid crystal material on the alignment layer at a speed of 1000 revolutions per minute for 30 seconds to complete the production of the single-piece liquid crystal layer.

[0021] Preferably, the preparation process of the reconfigurable chiral liquid crystal cell is as follows:

[0022] First substrate / second substrate pretreatment: The first substrate and the second substrate are ultrasonically cleaned with ITO cleaning solution for 30 minutes, then ultrasonically cleaned with ultrapure water twice repeatedly, each cleaning time is 10 minutes. The cleaned first substrate and second substrate are put into a drying oven, the temperature of the drying oven is 120 °C, and the drying duration is 40 minutes. Finally, the first substrate and the second substrate are subjected to ultraviolet ozone cleaning for 30 minutes;

[0023] Preparation of the first alignment layer: The first alignment layer material is spin-coated on the first substrate, and the molecules in the first alignment layer are arranged to point in a direction parallel to the plane of the first alignment layer;

[0024] Preparation of the second alignment layer: The second alignment layer material is deposited on the second substrate, and the molecules in the second alignment layer are arranged to point in a direction perpendicular to the plane of the second alignment layer;

[0025] Substrate bonding: 8-micron silica or polystyrene microspheres are selected and mixed with an ultraviolet-curable sealing adhesive. The mixture is evenly applied to the edge of the first substrate. The first substrate with the spin-coated first alignment layer and the second substrate with the spin-coated second alignment layer are bonded with a dislocation, and then placed under ultraviolet light until the ultraviolet-curable sealing adhesive cures. During bonding, the first alignment layer and the second alignment layer are arranged opposite to each other, and a accommodation space is left between the first alignment layer and the second alignment layer;

[0026] Preparation of the liquid crystal layer of the liquid crystal cell: The reconfigurable chiral liquid crystal material is filled into the accommodation space between the first alignment layer and the second alignment layer through a capillary tube.

[0027] Preferably, the preparation of the first alignment layer specifically includes the following steps:

[0028] Spin-coat the first alignment layer material on the first substrate at a speed of 800 revolutions per minute for 5 seconds;

[0029] Then spin-coat the first alignment layer material on the first substrate at a speed of 3000 revolutions per minute for 40 seconds;

[0030] After spin-coating the first alignment agent, anneal the first substrate with the spin-coated first alignment layer material. The annealing temperature is 100 °C and the annealing time is 10 minutes;

[0031] Then use 405 nm linearly polarized light to uniformly align the first alignment layer.

[0032] Preferably, the preparation of the second alignment layer specifically includes the following steps:

[0033] Prepare a solution of the second alignment layer material with a suitable concentration;

[0034] Immerse the second substrate in the solution of the second alignment layer material for 1 hour, and use ultrapure water to rinse off the excess molecules of the second alignment layer material;

[0035] Dry the second substrate with the deposited second alignment layer material. The drying temperature is 100 °C and the drying time is 60 minutes to form a second alignment layer with a vertical alignment effect on the second substrate.

[0036] Preferably, the steps for preparing the liquid crystal layer of the liquid crystal cell are as follows:

[0037] The light-driven chiral liquid crystal material is heated to 70°C and poured into the liquid crystal box through a capillary to complete the production of the liquid crystal layer of the liquid crystal box.

[0038] Preferably, the alignment layer material, the first alignment layer material and the second alignment layer material can be selected from any one of a surfactant, a rubbing alignment agent, a photo-crosslinking material, a photo-degradable material and a photoinduced cis-trans isomerization material;

[0039] Wherein, the alignment layer material is an azo-based photo-controlled alignment material SD1;

[0040] The material of the first alignment layer is an azo-based light-controlled alignment material SD1;

[0041] The second alignment layer material is a vertical alignment agent N,N-dimethyl-N-[3-(trimethoxysilyl)propyl]octadecyl ammonium chloride (DMOAP).

[0042] Preferably, the reconfigurable chiral liquid crystal material is prepared by fully mixing a photoisomerization material and a nematic liquid crystal in a mass ratio of 1:99;

[0043] The photoisomerization chiral agent can be selected from any one of azobenzene, indigo, olefin, and diarylethene chiral agents. The beneficial effects of the present invention are:

[0044] 1. The present invention provides a method for eliminating liquid crystal disclination lines, which can effectively eliminate liquid crystal disclination lines and ensure the optical performance of liquid crystal optical elements.

[0045] 2. The present invention provides a method for eliminating liquid crystal disclination lines. Compared with the prior art, the process is simple and highly controllable, and does not require long-term static state. It can quickly eliminate the disclination lines of liquid crystals doped with photo-isomerized materials, and can effectively improve the preparation efficiency and yield of liquid crystal optical elements. It has good application prospects in the field of preparation of liquid crystal optical elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a flow chart of the liquid crystal disclination line elimination method proposed by the present invention;

[0047] Figure 2 The figure is a flow chart of the preparation of the reconfigurable chiral liquid crystal single chip in the present invention;

[0048] Figure 3 It is a schematic diagram of the structure of the reconfigurable chiral liquid crystal single chip in the present invention;

[0049] Figure 4 The figure is a flow chart of the preparation of the reconfigurable chiral liquid crystal cell of the present invention;

[0050] Figure 5 is a schematic structural diagram of a reconfigurable chiral liquid crystal cell in the present invention;

[0051] Figure 6 This is a schematic structural diagram of the optical system for eliminating disclination lines in a photo-induced isomerization material-doped liquid crystal in the present invention;

[0052] Figure 7 This is a micrograph of a reconfigurable chiral liquid crystal single sheet without irradiated unwinding light in the first embodiment of the present invention;

[0053] Figure 8 This is a micrograph of a reconfigurable chiral liquid crystal single sheet irradiated with unwinding light but not with restoring light in the first embodiment of the present invention;

[0054] Figure 9 This is a micrograph of a reconfigurable chiral liquid crystal single sheet irradiated with both unwinding light and restoring light in the first embodiment of the present invention. Detailed implementation manners

[0055] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0056] Embodiment 1:

[0057] Please refer to Figures 1-3 As shown, the present invention provides a technical solution: a method for eliminating disclination lines in a reconfigurable chiral liquid crystal single sheet, including the following steps:

[0058] Use ITO cleaning solution to ultrasonically clean the substrate for 30 minutes, then repeatedly perform ultrasonic cleaning with ultrapure water twice, each time for 10 minutes. Put the cleaned substrate into a drying oven, the temperature of the drying oven is 120 °C, the drying duration is 40 minutes, and finally perform ultraviolet ozone cleaning on the substrate for 30 minutes;

[0059] Spin-coat the photo-controlled alignment material SD1 on the substrate at a speed of 800 revolutions per minute for 5 seconds;

[0060] Then spin-coat the photo-controlled alignment material SD1 on the substrate at a speed of 3000 revolutions per minute for 40 seconds;

[0061] After spin-coating the alignment agent, anneal the substrate spin-coated with the photo-controlled alignment material SD1, the annealing temperature is 100 °C, and the annealing time is 10 minutes;

[0062] Use 405 nm linearly polarized light to uniformly align the alignment layer. Use a 405 nm LED light source with a power of 1 W to 2 W, and directly perform uniform in-plane alignment on the alignment layer through a linear polarizer;

[0063] Mix the photo-isomerizable material, the left-handed azobenzene chiral molecular switch ChAD-3C-S, and the nematic liquid crystal in a mass ratio of 1:99 to prepare a reconfigurable chiral liquid crystal material;

[0064] Heat the reconfigurable chiral liquid crystal material to 70 °C, and then spin-coat the reconfigurable chiral liquid crystal material on the alignment layer at a speed of 1000 revolutions per minute for 30 seconds to complete the production of a single liquid crystal layer;

[0065] Please refer to Figure 6 As shown, build an optical system for eliminating disclination lines in liquid crystals doped with photo-isomerizable materials. Place the beam splitter and the single reconfigurable chiral liquid crystal on the outgoing direction of the 365 nm ultraviolet unwinding LED light source so that the unwinding light can irradiate the single liquid crystal. The beam splitter needs to be set at an angle of 45 degrees. The 530 nm green light recovery LED light source is set perpendicular to the outgoing direction of the unwinding light source. Through the reflection of the beam splitter, it is parallel to the outgoing direction of the unwinding light source so that the recovery light can irradiate the single liquid crystal;

[0066] Turn on the 365 nm ultraviolet unwinding LED light source to irradiate the single reconfigurable chiral liquid crystal. After irradiating the single reconfigurable chiral liquid crystal for 3 to 5 minutes, turn off the 365 nm ultraviolet unwinding LED light source;

[0067] Turn on the 530 nm green light recovery LED light source and irradiate the single reconfigurable chiral liquid crystal for 5 to 10 minutes, then turn off the 530 nm green light recovery LED light source.

[0068] In this embodiment, disclination lines in the liquid crystal will be generated when the reconfigurable chiral liquid crystal material is spin-coated. For the part of the reconfigurable chiral liquid crystal near the first alignment layer, the helical axis of the chiral structure is perpendicular to the first substrate. For the part of the reconfigurable chiral liquid crystal near the air, due to the alignment effect of air on the chiral liquid crystal being perpendicular to the direction of the first substrate, the helical axis deforms and gradually becomes parallel to the in-plane direction of the first substrate. Under a polarized light microscope, the helical structure shows alternating light and dark, and the overall structure is like a fingerprint, having optical properties that ordinary chiral liquid crystals do not have;

[0069] In this embodiment, the aligning agent of the alignment layer is an azo-based photo-controlled alignment material SD1. Under the irradiation of linearly polarized light, the SD1 molecules will be arranged along the direction perpendicular to the direction of the linearly polarized light.

[0070] In this implementation, the photo-controlled chiral dye in the reconfigurable chiral liquid crystal is the azo-based photo-controlled alignment material ChAD-3C-S. Under the irradiation of ultraviolet light (350 nm to 400 nm), the ChAD-3C-S molecules will undergo a trans-cis reaction, and the reconfigurable chiral liquid crystal will present an unwound state. Under the irradiation of green light (500 nm to 560 nm), the ChAD-3C-S molecules will undergo a cis-trans reaction, and the reconfigurable chiral liquid crystal will present a state of helix structure recovery.

[0071] Example 2:

[0072] Please refer to Figure 1 and Figures 4-5 As shown, on the basis of Example 1, the present invention provides a method for eliminating the disclination line of the liquid crystal in a reconfigurable chiral liquid crystal cell, including the following steps:

[0073] Use ITO cleaning solution to ultrasonically clean the first substrate and the second substrate for 30 minutes, and then repeatedly perform ultrasonically cleaning with ultrapure water twice, each cleaning time is 10 minutes. Put the cleaned first substrate and the second substrate into a drying oven, the temperature of the drying oven is 120 °C, the drying time is 40 minutes, and finally perform ultraviolet ozone cleaning on the first substrate and the second substrate for 30 minutes;

[0074] Spin-coat the photo-controlled alignment material SD1 on the first substrate at a speed of 800 revolutions per minute for 5 seconds;

[0075] Then spin-coat the photo-controlled alignment material SD1 on the first substrate at a speed of 3000 revolutions per minute for 40 seconds;

[0076] After spin-coating the first alignment agent, anneal the first substrate spin-coated with the photo-controlled alignment material SD1, the annealing temperature is 100 °C, and the annealing time is 10 minutes;

[0077] Then use 405 nm linearly polarized light to uniformly align the photo-controlled alignment material SD1. Use a 405 nm LED light source of 1 W to 2 W, pass through a linear polarizer, and directly perform uniform in-plane alignment on the first alignment layer;

[0078] Prepare a DMOAP solution with a volume concentration of 3%, and the other solvent is ultrapure water;

[0079] After soaking the second substrate in the DMOAP solution for 1 hour, use ultrapure water to rinse off the excessive DMOAP molecules;

[0080] Then place it in a drying oven and bake it at 100 °C for one hour, then a second alignment layer with a vertical alignment effect is formed on the second substrate;

[0081] 8 micron silicon dioxide or polystyrene microspheres are selected and mixed with UV curing sealant, and evenly applied to the edge of the first substrate, and the first substrate on which the first alignment layer is spin-coated and the second substrate on which the second alignment layer is spin-coated are staggered and bonded, and placed under UV light until the UV curing sealant is cured. During bonding, the first alignment layer and the second alignment layer are arranged opposite to each other, and an accommodation space is left between the first alignment layer and the second alignment layer;

[0082] The photoisomerizable material L-azobenzene chiral molecular switch ChAD-3C-S was fully mixed with nematic liquid crystal at a mass ratio of 1:99 to prepare a reconfigurable chiral liquid crystal material.

[0083] injecting the reconfigurable chiral liquid crystal material into the accommodation space between the first alignment layer and the second alignment layer through a capillary;

[0084] See also Figure 6 As shown, an optical system for eliminating the disclination line of the liquid crystal doped with the photo-isomerized material is constructed, and the beam splitter and the reconfigurable chiral liquid crystal box are set in the emitting direction of the 365nm ultraviolet derotation LED light source, so that the derotation light can be irradiated on the reconfigurable chiral liquid crystal box. The beam splitter needs to be set at an angle of 45 degrees, and the 530nm green light recovery LED light source is set perpendicular to the emitting direction of the derotation light source. Through the reflection of the beam splitter, it is parallel to the emitting direction of the derotation light source, so that the recovery light can be irradiated on the reconfigurable chiral liquid crystal box;

[0085] Turning on a 365nm ultraviolet derotation LED light source to irradiate the derotation light onto the reconfigurable chiral liquid crystal box, irradiating the reconfigurable chiral liquid crystal box for 3 to 5 minutes, and then turning off the 365nm ultraviolet derotation LED light source;

[0086] The 530nm green light recovery LED light source is turned on, irradiated to the reconfigurable chiral liquid crystal box for 5 to 10 minutes, and then the 530nm green light recovery LED light source is turned off.

[0087] In this embodiment: the liquid crystal disclination lines will be generated when the reconfigurable chiral liquid crystal material is poured between the first and second orientation layers. In the reconfigurable chiral liquid crystal part close to the first orientation layer, the spiral axis of the chiral structure is perpendicular to the first substrate. In the reconfigurable chiral liquid crystal part close to the second orientation layer, because the orientation effect of the second orientation layer on the chiral liquid crystal is perpendicular to the direction of the second substrate, the spiral axis is deformed and gradually parallel to the in-plane direction of the second substrate. Under a polarizing microscope, the spiral structure shows alternating light and dark. The overall structure is like a fingerprint, and has optical properties that ordinary chiral liquid crystals do not have.

[0088] In this embodiment: the alignment agent of the first alignment layer is an azo-based photo-controlled alignment material SD1, and under the irradiation of linear polarized light, the SD1 molecules will be arranged in a direction perpendicular to the direction of the linear polarized light.

[0089] In this embodiment: The vertical alignment agent of the second alignment layer is DMOAP. The silane molecules possessed by this alignment agent can vertically anchor liquid crystal molecules, thereby causing the liquid crystal molecules to be arranged perpendicular to the substrate.

[0090] In this embodiment: The photo-controllable chiral dye in the reconfigurable chiral liquid crystal is the azo-based photo-controllable alignment material ChAD-3C-S. Under the irradiation of ultraviolet light (350 nm to 400 nm), the ChAD-3C-S molecules will undergo a trans-cis reaction, and the reconfigurable chiral liquid crystal will present a de-twisted state. Under the irradiation of green light (500 nm to 560 nm), the ChAD-3C-S molecules will undergo a cis-trans reaction, and the reconfigurable chiral liquid crystal will present a state of recovery of the helical structure.

[0091] It should be specifically noted that: The alignment layer materials, the first alignment layer materials, and the second alignment layer materials in this solution include but are not limited to the materials mentioned in Example 1 and Example 2. The alignment layer materials, the first alignment layer materials, and the second alignment layer materials in this solution can be any one of surfactants, rubbing alignment agents, photocrosslinkable materials, photodegradable materials, and photo-induced cis-trans isomerism materials;

[0092] The photo-induced isomeric chiral agents in this solution include but are not limited to the material left-handed azobenzene chiral molecular switch ChAD-3C-S mentioned in Example 1 and Example 2. The photo-induced isomeric chiral agents in this solution can be any one of azobenzene-based, indigo-based, olefin-based, diarylethene-based chiral agents.

[0093] Performance test:

[0094] For the single reconfigurable chiral liquid crystal sheet in Example 1 that was not irradiated with de-twisting light, a polarizing microscope was used to observe the disclination lines of the liquid crystal sample. The results are as Figure 7 shown. It can be seen that disclination lines exist in most regions;

[0095] For the single reconfigurable chiral liquid crystal sheet in Example 1 that was irradiated with de-twisting light but not irradiated with recovery light, a polarizing microscope was used to observe the disclination lines of the liquid crystal sample. The results are as Figure 8 shown. It can be seen that the disclination lines in most regions disappear;

[0096] For the single reconfigurable chiral liquid crystal sheet in Example 1 that was irradiated with de-twisting light and recovery light, a polarizing microscope was used to observe the disclination lines of the liquid crystal sample. The results are as Figure 9 shown. It can be seen that the disclination lines in most regions disappear, and at the same time, the helical structure of the liquid crystal is restored.

[0097] In summary, the advantages of the present invention are as follows: It provides a method for eliminating liquid crystal disclination lines. Its process is relatively simpler and more controllable compared with the prior art means. It does not require long-term static placement and can quickly eliminate the photoinduced isomerism material-doped liquid crystal disclination lines, effectively improving the preparation efficiency and yield of liquid crystal optical elements, and having good application prospects in the field of preparation of liquid crystal optical elements.

[0098] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0099] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for eliminating liquid crystal disclination lines, characterized in that, It includes the following steps: Prepare a reconfigurable chiral liquid crystal system, which includes reconfigurable chiral liquid crystal on a single chip and reconfigurable chiral liquid crystal in a liquid crystal cell; Set up an optical system for eliminating disclination lines of liquid crystal doped with photo-isomerizable material, which includes an ultraviolet unwinding light source, a green restoring light source, and a beam splitter; The reconfigurable chiral liquid crystal single chip or the reconfigurable chiral liquid crystal cell is arranged in the outgoing direction of the ultraviolet unwinding light source. The beam splitter is inclined at 45 degrees and arranged between the ultraviolet unwinding light source and the reconfigurable chiral liquid crystal single chip or the reconfigurable chiral liquid crystal cell. The green light restoring light source is arranged perpendicular to the outgoing direction of the ultraviolet unwinding light source and, through reflection by the beam splitter, is parallel to the outgoing direction of the ultraviolet unwinding light source; Start the ultraviolet unwinding light source to emit unwinding light, make the ultraviolet unwinding light vertically irradiate on the reconfigurable chiral liquid crystal single chip or the reconfigurable chiral liquid crystal cell, and after irradiating for 3 to 5 minutes, turn off the ultraviolet unwinding light source; Start the green restoring light source to emit restoring light, and adjust the optical path through the beam splitter to make the restoring light vertically irradiate on the reconfigurable chiral liquid crystal single chip or the reconfigurable chiral liquid crystal cell, and after irradiating for 5 to 10 minutes, turn off the green restoring light source; The photo-controlled chiral dye in the reconfigurable chiral liquid crystal will undergo a trans-cis reaction under the irradiation of ultraviolet light, and the reconfigurable chiral liquid crystal will present an unwound state. Under the irradiation of green light, the molecule will undergo a cis-trans reaction, and the reconfigurable chiral liquid crystal will present a state of helix structure restoration.

2. The method for eliminating the liquid crystal disclination line according to claim 1, wherein, The preparation process of the reconfigurable chiral liquid crystal single chip on the single chip is as follows: Substrate pretreatment: Use ITO cleaning solution to ultrasonically clean the substrate for 30 minutes, then repeatedly perform ultrasonically cleaning with ultrapure water twice, each cleaning time is 10 minutes. Put the cleaned substrate into a drying oven, the temperature of the drying oven is 120 °C, the drying time is 40 minutes, and finally perform ultraviolet ozone cleaning on the substrate for 30 minutes; Alignment layer preparation: Spin-coat the alignment layer material on the substrate and make the molecules in the alignment layer align parallel to the direction within the alignment layer plane; Single-chip liquid crystal layer preparation: Spin-coat the reconfigurable chiral liquid crystal material on the alignment layer by the spin-coating method. Under the combined action of the alignment layer and air, the liquid crystal layer molecules will self-assemble to form a multi-level chiral structure with symmetry breaking.

3. A method for eliminating liquid crystal disclination lines according to claim 2, characterized in that, The alignment layer preparation specifically includes the following steps: Spin-coat the alignment layer material on the substrate at a speed of 800 revolutions per minute for 5 seconds; Then spin-coat the alignment layer material on the substrate at a speed of 3000 revolutions per minute for 40 seconds; After spin-coating the alignment agent, anneal the substrate spin-coated with the alignment layer material, the annealing temperature is 100 °C, and the annealing time is 10 minutes; Use 405 nm linearly polarized light to uniformly align the alignment layer.

4. A method for eliminating liquid crystal disclination lines according to claim 3, characterized in that, The single-chip liquid crystal layer preparation specifically includes the following steps: Heat the reconfigurable chiral liquid crystal material to 70 °C, and then spin-coat the reconfigurable chiral liquid crystal material on the alignment layer at a speed of 1000 revolutions per minute for 30 seconds to complete the production of the single-chip liquid crystal layer.

5. A method for eliminating liquid crystal disclination lines according to claim 1, characterized in that, The preparation process of the reconfigurable chiral liquid crystal cell is as follows: Pretreatment of the first substrate and the second substrate: The first substrate and the second substrate are ultrasonically cleaned with ITO cleaning solution for 30 minutes, and then ultrasonically cleaned with ultrapure water twice repeatedly, with each cleaning time being 10 minutes. The cleaned first substrate and second substrate are placed in a drying oven at a temperature of 120 °C for 40 minutes of drying. Finally, the first substrate and the second substrate are subjected to ultraviolet ozone cleaning for 30 minutes; Preparation of the first alignment layer: The first alignment layer material is spin-coated on the first substrate, and the molecules in the first alignment layer are arranged to point parallel to the direction within the plane of the first alignment layer; Preparation of the second alignment layer: The second alignment layer material is deposited on the second substrate, and the molecules in the second alignment layer are arranged to point perpendicular to the direction within the plane of the second alignment layer; Substrate bonding: 8-micron silica or polystyrene microspheres are selected and mixed with an ultraviolet-curable sealing adhesive, and evenly applied to the edge of the first substrate. The first substrate with the spin-coated first alignment layer and the second substrate with the spin-coated second alignment layer are misaligned and bonded, and placed under ultraviolet light until the ultraviolet-curable sealing adhesive cures. During bonding, the first alignment layer and the second alignment layer are arranged opposite to each other, and a accommodation space is left between the first alignment layer and the second alignment layer; Preparation of the liquid crystal layer of the liquid crystal cell: The reconfigurable chiral liquid crystal material is filled into the accommodation space between the first alignment layer and the second alignment layer through a capillary tube.

6. A method for eliminating liquid crystal disclination lines according to claim 5, characterized in that, The preparation of the first alignment layer specifically includes the following steps: Spin-coat the first alignment layer material on the first substrate at a speed of 800 revolutions per minute for 5 seconds; Then spin-coat the first alignment layer material on the first substrate at a speed of 3000 revolutions per minute for 40 seconds; After spin-coating the first alignment agent, the first substrate spin-coated with the first alignment layer material is annealed at an annealing temperature of 100 °C for 10 minutes; Then, 405 nm linearly polarized light is used to uniformly align the first alignment layer.

7. A method for eliminating a liquid crystal disclination line according to claim 6, characterized in that, The preparation of the second alignment layer specifically includes the following steps: Prepare a solution of the second alignment layer material with a suitable concentration; Immerse the second substrate in the second alignment layer material solution for 1 hour, and use ultrapure water to rinse off the excess second alignment layer material molecules; Dry the second substrate deposited with the second alignment layer material at a drying temperature of 100 °C for 60 minutes to form a second alignment layer with a vertical alignment effect on the second substrate.

8. A method for eliminating liquid crystal disclination lines according to claim 6, characterized in that: The steps for preparing the liquid crystal layer of the liquid crystal cell are: Heat the light-driven chiral liquid crystal material to 70 °C, and fill it into the liquid crystal cell through a capillary tube to complete the production of the liquid crystal layer of the liquid crystal cell.

9. A method for eliminating liquid crystal disclination lines according to any one of claims 2-8, characterized in that, The alignment layer material, the first alignment layer material, and the second alignment layer material can be any one of surfactants, rubbing alignment agents, photocrosslinkable materials, photodegradable materials, and photo-induced cis-trans isomer materials; Among them, the alignment layer material is the azo-based light-controlled alignment material SD1; The first alignment layer material is the azo-based light-controlled alignment material SD1; The second alignment layer material is the vertical alignment agent N,N-dimethyl-N-[3-(trimethoxysilyl)propyl] octadecylammonium chloride (DMOAP).

10. A method for eliminating liquid crystal disclination lines according to any one of claims 9, characterized in that, The reconfigurable chiral liquid crystal material is made by fully mixing a photo-isomerizable material and a nematic liquid crystal in a mass ratio of 1:99; Among them, the photo-isomerizable chiral agent can be any one of azobenzene-based, indigo-based, olefin-based, and diarylethene-based chiral agents.

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