阅读说明：本技术 一种用于粒子操控的近晶相液晶多层装置及粒子操控方法 (Smectic phase liquid crystal multilayer device for particle manipulation and particle manipulation method ) 是由 郭清仪 葛士军 吴赛博 于 2020-06-23 设计创作，主要内容包括：本发明公开了一种用于粒子操控的近晶相液晶多层装置及粒子操控方法,包括从下至上依次设置的基板、取向膜、LCP层、粒子溶液涂层和近晶相液晶层；取向膜具有分子指向矢呈设定分布的控制图形,以使液晶层中的液晶分子自组装成设定的液晶焦锥畴周期结构,液晶焦锥畴周期结构包含多个具有旋转对称性的液晶焦锥畴。本发明工艺简单,易于实现,且成本较低,无需现有技术中对粒子及液晶进行相容基团修饰的步骤,降低了技术难度及时间成本。(The invention discloses a smectic phase liquid crystal multilayer device for particle control and a particle control method, wherein the smectic phase liquid crystal multilayer device comprises a substrate, an orientation film, an LCP (liquid crystal display) layer, a particle solution coating and a smectic phase liquid crystal layer which are arranged in sequence from bottom to top; the orientation film is provided with a control pattern with a set distribution of molecular directors, so that liquid crystal molecules in the liquid crystal layer are self-assembled into a set liquid crystal focal conic domain periodic structure, and the liquid crystal focal conic domain periodic structure comprises a plurality of liquid crystal focal conic domains with rotational symmetry. The method has the advantages of simple process, easy realization and lower cost, does not need the step of modifying compatible groups of particles and liquid crystal in the prior art, and reduces the technical difficulty and time cost.)

1. A smectic liquid crystal multilayer device for particle manipulation, comprising: the liquid crystal display device comprises a substrate, an orientation film, an LCP layer, a particle solution coating and a smectic phase liquid crystal layer which are sequentially arranged from bottom to top; the orientation film is provided with a control pattern with a set distribution of molecular directors, so that liquid crystal molecules in the liquid crystal layer are self-assembled into a set liquid crystal focal conic domain periodic structure, and the liquid crystal focal conic domain periodic structure comprises a plurality of liquid crystal focal conic domains with rotational symmetry.

2. The smectic liquid crystal multilayer device as claimed in claim 1, wherein: the orientation film has a control pattern with a latticed molecular director distribution, so that liquid crystal molecules in the liquid crystal layer are self-assembled into a liquid crystal focal conic domain array.

3. The smectic liquid crystal multilayer device as claimed in claim 2, wherein: the control pattern is in a check shape or a diamond shape.

4. The smectic liquid crystal multilayer device as claimed in claim 3, wherein: the alignment film has a latticed pattern with continuously changing directors, wherein the latticed pattern comprises a plurality of square unit cells, and the side length of each unit cell is 12-20 mu m.

5. The smectic liquid crystal device as claimed in claim 1, wherein: the orientation film is a photoalignment film.

6. The smectic liquid crystal multilayer device as claimed in claim 1, wherein: the particles in the particle solution coating are quantum dots or fluorescent microspheres.

7. The smectic liquid crystal multilayer device as claimed in claim 6, wherein: the particles in the particle solution coating are CsPbBr₃A perovskite quantum rod.

8. The method of claim 1, wherein the method comprises:

(1) arranging an orientation film on one side of a substrate, and carrying out orientation treatment on the orientation film to enable the orientation film to be in a control pattern with set distribution;

(2) coating an LCP layer on the orientation film to repeatedly etch the control pattern on the orientation film;

(3) sequentially arranging a particle solution coating and a smectic phase liquid crystal layer on the LCP layer; so that liquid crystal molecules in the liquid crystal layer are self-assembled into a set liquid crystal focal conic domain periodic structure, and fixed-point control of particles is realized.

9. The method of claim 8, wherein: the orientation treatment of the orientation film adopts photo-orientation continuous exposure or binary exposure.

10. The method of claim 8, wherein: the concentration of the particles in the particle solution coating is 0.1-5 mg/mL.

Technical Field

The present invention relates to a liquid crystal device and a particle manipulation method thereof, and more particularly, to a smectic multilayer liquid crystal device and a particle manipulation method thereof.

Background

The liquid crystal is a substance phase state with the order degree between solid state and liquid state, and the multi-level structure of the liquid crystal has wider technical application in the fields of light field regulation, micro lens array, particle control and the like. In recent years, applications based on smectic phase liquid crystal multi-level structures have emerged, especially in the field of particle manipulation. At present, a series of control means of smectic phase liquid crystal multi-level structures with different dimensions, such as patterned substrate surface control, three-dimensional geometrical structure limitation of a silicon substrate, two-dimensional surface orientation induction and the like. However, in the current manipulation of smectic phase liquid crystal multi-layer structured nanoparticles, the modification of similar compatible groups is mostly needed for liquid crystal and nanoparticles, so the problems of low efficiency and complex operation are faced.

Disclosure of Invention

The purpose of the invention is as follows: it is an object of the present invention to provide a smectic liquid crystal multilayer device for particle manipulation that can disperse nanoparticles well in a liquid crystal system without modification of the particles with the liquid crystal; another object of the present invention is to provide a method for manipulating particles of a smectic liquid crystal multilayer device.

The technical scheme is as follows: the smectic phase liquid crystal multilayer device comprises a substrate, an orientation film, an LCP layer, a particle solution coating and a smectic phase liquid crystal layer which are arranged in sequence from bottom to top; the orientation film is provided with a control pattern with a set distribution of molecular directors, so that liquid crystal molecules in the liquid crystal layer are self-assembled into a set liquid crystal focal conic domain periodic structure, and the liquid crystal focal conic domain periodic structure comprises a plurality of liquid crystal focal conic domains with rotational symmetry.

The LCP is a full-scale industrial liquid crystal polymer, has outstanding heat resistance and corrosion resistance, plays a role in stabilizing and re-engraving oriented film patterns in the device structure, and is formed by coating the LCP; the particle solution coating is formed by coating particles after the particles are dissolved in an organic solution.

Wherein the particles are quantum dots or fluorescent microspheres, and the concentration of the particles is 0.1-5 mg/mL.

The liquid crystal focal conic domain periodic structure is a liquid crystal focal conic domain array; the orientation film has a pattern which makes the distribution of molecular director in central symmetry periodic distribution, so that the liquid crystal molecules in the liquid crystal layer are self-assembled to form a liquid crystal focal conic domain array and other structural arrays, and different arrays have different effects on particles due to different micro-pattern pitches and pattern symmetries.

The molecular director distribution of the orientation film and the grown liquid crystal focal conic domain periodic structure have various setting modes, and optionally, the liquid crystal focal conic domain periodic structure is a plurality of smectic phase defect structures such as a toroidal focal conic domain, a square focal conic domain and the like to control the particles; the molecular director distribution of the orientation film corresponding to the toroidal focal conic domain and the square focal conic domain is the prior art.

Wherein the smectic phase liquid crystal layer can be made of smectic phase liquid crystal 8CB, and the spin coating speed range of the smectic phase liquid crystal layer is 2000r/s-2400 r/s; the material of the orientation film is at least one of a photo-crosslinking material, a photo-degradable material and a photo-cis-trans isomeric material; the photo-induced cis-trans isomerism material used for the orientation film can be an azo photo-control orientation material SD 1.

Preferably, the alignment film has a control pattern in which the molecular directors are distributed in a lattice shape, so that liquid crystal molecules in the liquid crystal layer are self-assembled into a liquid crystal focal domain array; optionally, the trellis control pattern includes a plurality of rows and a plurality of columns of cells.

Preferably, the control pattern is in a grid shape or a rhombus grid shape; when the control graph is in a grid shape, continuous exposure is adopted, and smectic phase liquid crystal can be induced to grow out a ring curved surface focal conic domain defect structure with a corresponding size; when the control pattern is in a rhombohedral shape, the control pattern is combined with binary exposure to induce smectic phase liquid crystal to grow a square focal conic domain defect structure with a corresponding size.

Preferably, the alignment film has a latticed pattern in which directors vary continuously, the latticed pattern including a plurality of square cells, and the sides of the cells are 12 to 20 μm.

Preferably, the alignment film is a light control alignment film.

Preferably, the particles in the particle solution coating are quantum dots or fluorescent microspheres. Namely, the smectic phase liquid crystal device can select quantum dots and fluorescent SiO₂And a plurality of materials such as small balls are used as objects to be controlled.

Further, the particles in the particle solution coating are CsPbBr₃The perovskite particles can be CsPbBr with the size of about 11nm × 11nm × (50-100 nm)₃The perovskite quantum rod has the length, width, height and size of 11nm, 11nm and 50-100 nm respectively.

The invention also provides a particle control method of the smectic phase liquid crystal device, which comprises the following steps:

(1) arranging an orientation film on one side of a substrate, and carrying out orientation treatment on the orientation film to enable the orientation film to be in a control pattern with set distribution;

(2) coating an LCP layer on the orientation film to repeatedly etch the control pattern on the orientation film;

(3) sequentially arranging a particle solution coating and a smectic phase liquid crystal layer on the LCP layer; so that liquid crystal molecules in the liquid crystal layer are self-assembled into a set liquid crystal focal conic domain periodic structure, and fixed-point control of particles is realized.

The orientation treatment of the orientation film adopts light-operated orientation continuous exposure or binary exposure; optionally, when the control pattern is in a grid shape, continuous exposure is adopted, and smectic phase liquid crystal can be induced to grow out a ring curved surface focal conic domain defect structure with a corresponding size; when the control pattern is in a rhombohedral shape, binary exposure is adopted to induce smectic phase liquid crystal to grow a square focal conic domain defect structure with a corresponding size.

The invention principle is as follows: the invention relates to a particle control system based on smectic phase liquid crystal, which is coated in a layered way, wherein an orientation film of the particle control system has a control pattern with molecular directors in set distribution; the LCP layer is repeatedly etched with patterns on the orientation film, and the orientation film is replaced to have anchoring effect on liquid crystal molecules in the liquid crystal layer, so that the arrangement of molecular directors of the liquid crystal molecules in the liquid crystal layer adjacent to the LCP layer is the same as that of the molecular directors of the LCP layer; under the anchoring action of the LCP layer on liquid crystal molecules in the liquid crystal layer and the anchoring action of air on the liquid crystal layer far away from the LCP layer on the liquid crystal, the liquid crystal molecules in the liquid crystal layer are self-assembled into a set liquid crystal focal conic domain periodic structure; the particle solution coating is fused with the liquid crystal layer after drying and manipulated by its fixed point.

Wherein, the liquid crystal focal conic domain periodic structure is a liquid crystal focal conic domain array; the orientation film has a pattern which makes the distribution of molecular director in central symmetry periodic distribution, so that the liquid crystal molecules in the liquid crystal layer are self-assembled to form a liquid crystal focal conic domain array and other structural arrays, and different arrays have different effects on particles due to different micro-pattern pitches and pattern symmetries.

Meanwhile, the invention combines the light-operated orientation exposure technology based on the DMD micro-mirror system with the control of the smectic phase liquid crystal multi-level structure nano particles, thereby realizing the control of the smectic phase liquid crystal multi-level structure on the nano particles.

Has the advantages that: the device based on smectic phase liquid crystal realizes the control of nano particles, and enables a liquid crystal focal conic domain periodic structure to grow on one side of an LCP layer by controlling the distribution of molecular director of an orientation film; compared with the particle control means in the prior art, the method has the advantages of simple process, easy realization and lower cost by combining different exposure processes, does not need the step of modifying compatible groups of particles and liquid crystals in the prior art, and reduces the technical difficulty and time cost.

Drawings

FIG. 1 is a schematic view of a smectic phase liquid crystal multilayer device of example 1 of the present invention;

FIG. 2 is a schematic view of an exposure pattern of an alignment layer in example 1 of the present invention;

FIG. 3 is a microscopic weave of the LCP layer and the liquid crystal layer anchored by it in example 1 of the present invention; wherein (a) is the weave pattern of the LCP layer and (b) is the weave pattern of the liquid crystal layer;

FIG. 4 is a schematic diagram showing a particle manipulation effect according to embodiment 1 of the present invention;

FIG. 5 is a schematic view of a smectic liquid crystal-based particle manipulation system in example 2 of the present invention;

FIG. 6 is a schematic diagram of the exposure pattern of the alignment layer of a smectic liquid crystal based particle manipulation system in example 2 of the present invention;

FIG. 7 is a microscopic weave of an LCP layer of example 2 of the invention and a liquid crystal layer anchored by it; wherein (a) is the weave pattern of the LCP layer and (b) is the weave pattern of the liquid crystal layer;

fig. 8 is a schematic view of a particle manipulation effect according to embodiment 2 of the present invention;

FIG. 9 is a schematic view of a smectic liquid crystal-based particle manipulation system in accordance with example 3 of the present invention;

FIG. 10 is a schematic view of the exposure pattern of the alignment layer of a smectic liquid crystal based particle manipulation system in example 3 of the present invention;

FIG. 11 is a microscopic weave of an LCP layer of example 3 of the invention and a liquid crystal layer anchored by it; wherein (a) is the weave pattern of the LCP layer, and (b) is the weave pattern of the liquid crystal layer;

Detailed Description

The present invention will be described in further detail with reference to examples.

The starting materials and reagents used in the following examples are all commercially available.