CN106833679A - The preparation method of the holographic 3D display screens of CdSe quantum dots doped liquid crystal material - Google Patents

Abstract

The invention discloses a method for preparing a holographic 3D display screen with cadmium selenide quantum dots doped with liquid crystal materials. According to a certain ratio, cadmium selenide quantum dots are mixed into liquid crystals to form a holographic material, and then the material is injected into two A holographic 3D display is formed in a piece of ITO glass. The invention prepares cadmium selenide quantum dots and mixes liquid crystals to form a holographic material. The system selects object light and reference light from laser light, and readout light from visible light. The holographic display material prepared by the present invention provides a carrier for holographic true 3D display, so that the material has dynamic refresh characteristics in the holographic display system, improves the diffraction efficiency, and shortens the response time. The holographic 3D display screen can be applied to holographic printing, holographic Optical disc, real-time dynamic holographic display, holographic photography and other fields.

Description

Preparation method of holographic 3D display screen doped with cadmium selenide quantum dots liquid crystal material

technical field

The invention relates to a method for preparing a liquid crystal display, in particular to a method for preparing a 3D display, and also to a method for preparing a holographic medium, which is applied in the technical field of electroluminescent display devices.

Background technique

Liquid crystals are an intermediate phase between crystalline solids and isotropic liquids. In a certain temperature range, the liquid crystal material in the liquid crystal phase has both anisotropy similar to crystals and fluidity like ordinary liquids. Liquid crystal exhibits anisotropy due to its elongated rod-like molecular structure, which results in different physical properties in the axial direction of the molecule and in the direction perpendicular to the axial direction of the molecule. According to the research progress on the photorefractive characteristics of liquid crystals in recent years, it can be seen that the incorporation of quantum dots into liquid crystals has greatly improved the nonlinearity of liquid crystals, which makes liquid crystals have important applications in optical information processing, holographic storage, etc. Significance. At the same time, because quantum dot materials are current research hotspots, they have unique physical properties such as quantum size effects and surface effects compared with bulk materials. The existing holographic 3D display materials have low diffraction efficiency, long response time, and unsatisfactory performance, which cannot meet the needs of the development of new display product industries.

CdSe quantum dots are quasi-zero-dimensional nanomaterials, composed of a small number of atoms. Generally speaking, the three dimensions of quantum dots are all at the nanometer level, and the appearance is just like a very small point. The movement of electrons in it is restricted in all directions, so the quantum confinement effect is particularly significant. Scientists have invented many different methods to manufacture quantum dots, and it is expected that this nanomaterial has great application potential in nanoelectronics in the 21st century, but there is no application of cadmium selenide quantum dots in 3D display. screen records.

Contents of the invention

In order to solve the problems of the prior art, the purpose of the present invention is to overcome the deficiencies in the prior art, to provide a method for preparing a holographic 3D display screen doped with cadmium selenide quantum dots, which can prepare cadmium selenide quantum dots doped Liquid crystal material forms a holographic 3D display medium, that is, the dielectric constant of the holographic 3D display material is changed by arranging liquid crystals containing quantum dots in a certain ratio, and the unique quantum size effect, surface effect and other physical properties can make the holographic display material The diffraction efficiency is improved, the response speed becomes faster, and finally a holographic 3D display with good performance is prepared.

In order to achieve the above invention creation purpose, the present invention adopts the following technical solutions:

A method for preparing a holographic 3D display screen doped with a cadmium selenide quantum dot liquid crystal material, comprising the steps of:

(1) Preparation of cadmium selenide quantum dot doped liquid crystal material:

When doping cadmium selenide quantum dots in liquid crystals to prepare holographic 3D display materials, according to the weight percentage calculation method, the doping weight ratio of cadmium selenide quantum dots is 0.01-10%, and the total weight of liquid crystals is 90-99.99%. Add the quantum dots to the liquid crystal to form a liquid crystal solution, and mix the prepared liquid crystal solution evenly to obtain a quantum dot-doped liquid crystal holographic 3D display material mixture; as the preferred technical solution of the present invention, the cadmium selenide quantum dots used are Composed of a limited number of atoms, the maximum diameter of cadmium selenide quantum dots is 0.2-900nm, and the three dimensions are all on the order of nanometers; as the preferred technical solution of the present invention, the cadmium selenide quantum dots used are spherical or similar Three-dimensional system such as spherical, cadmium selenide quantum dots also contain nanoparticles made of semiconductor materials composed of IIB～VIA or IIIA～VA elements; as a preferred technical solution of the present invention, the material of liquid crystal can be smectic phase liquid crystal, cholesteric liquid crystal, and nematic liquid crystal; doping cadmium selenide quantum dots in the liquid crystal, mixing the prepared liquid crystal solution evenly, so that the cadmium selenide quantum dots are dissolved in the liquid crystal and reach a saturated state;

(2) Preparation of liquid crystal cell:

a. Use glass with ITO conductive film as the ITO glass substrate. ITO is an N-type oxide semiconductor-indium tin oxide, and the ITO film is the transparent conductive film of indium tin oxide semiconductor. Cut the ITO glass substrate into design After cleaning, ultrasonication, and baking, the ITO glass substrate is cleaned, and two clean ITO glass substrates are taken out, and evenly coated with a polymer with a concentration of not less than 0.01-2wt.%. Vinyl alcohol organic solution forms a polyvinyl alcohol coating on the ITO glass substrate, and then bakes it in an oven to cure the polyvinyl alcohol coating on the surface of the ITO glass substrate;

b. Take out the two baked ITO glass substrates coated with polyvinyl alcohol, then place a polyester film between the two ITO glass substrates, and control the thickness of the gap between the two ITO glass substrates, Form a liquid crystal cell with a slit chamber structure; preferably determine the thickness of the liquid crystal cell by adjusting the thickness of the polyester film;

(3) Preparation of holographic 3D display screen:

ⅰ. Using the holographic 3D display material mixed solution prepared in the step (1), take the supernatant of the holographic 3D display material mixed solution, and use the capillary drainage method to extract the supernatant of the holographic 3D display material mixed solution Pour into the slit chamber of the liquid crystal cell prepared in the b step of said step (2), in the liquid crystal cell, the first layer of liquid crystal molecules at the liquid crystal and glass interface are arranged neatly in a specific direction, Obtain a liquid crystal micro unit;

ii. Combining a series of liquid crystal microunits prepared in the step i to form a cadmium selenide quantum dot-doped liquid crystal holographic 3D display.

As a preferred technical solution of the present invention, during the preparation process of the holographic 3D display screen, it is kept in a dry environment at room temperature.

Compared with the prior art, the present invention has the following obvious outstanding substantive features and significant advantages:

1. The present invention prepares cadmium selenide quantum dots mixed with nematic liquid crystals to form a holographic material, which provides a carrier for holographic true 3D display. The holographic 3D display screen prepared by the present invention is widely used in hologram printing, holographic discs, real-time dynamic holographic It shows that holography has significant application prospects in the field of holographic imaging technology;

2. The preparation method of the cadmium selenide quantum dot-doped liquid crystal holographic 3D display material of the present invention has a simple operation process and easy realization of the optical path, laying the foundation for the subsequent realization of dynamic image refresh;

3. The cadmium selenide quantum dot doped liquid crystal holographic 3D display material prepared by the present invention improves the diffraction efficiency and response time of the holographic 3D display material, and lays a solid foundation for the later development of a holographic 3D display with large size, large depth of field, and high resolution. base.

Description of drawings

Fig. 1 is a working principle diagram of a holographic 3D display screen prepared by a method according to Embodiment 1 of the present invention applied to a two-wave coupling optical path holographic 3D display system.

Fig. 2 is the response curve of the cadmium selenide quantum dot-doped liquid crystal prepared by the first method of the present invention under the action of voltage drive, wherein, Fig. 2 (a) is the hologram establishment time curve, and the response time is 50ms～1s, Fig. 2 (b) is the erasing time curve of the hologram, and the response time is 50ms～1s.

Fig. 3 shows the light diffraction speckle image read out on the receiving screen when the holographic 3D display screen prepared by the method of Embodiment 1 of the present invention is applied to a two-wave coupling optical path holographic 3D display system.

detailed description

Preferred embodiments of the present invention are described in detail as follows:

Embodiment one:

In this embodiment, referring to Figs. 1-3, a method for preparing a holographic 3D display screen with cadmium selenide quantum dots doped with liquid crystal material comprises the following steps:

(1) Preparation of cadmium selenide quantum dot doped liquid crystal material:

When doping cadmium selenide quantum dots in liquid crystals to prepare holographic 3D display materials, according to the weight percentage calculation method, the doping weight ratio of cadmium selenide quantum dots is 0.01-10%, and the total weight of liquid crystals is 90-99.99%. Add the quantum dots to the liquid crystal to form a liquid crystal solution, put the prepared liquid crystal solution into an ultrasonic vibrator and shake it, mix it well, and integrate the quantum dots into the liquid crystal better, after at least two days of standing, the quantum dots are obtained Doped liquid crystal holographic 3D display material mixture; the cadmium selenide quantum dots used are composed of a limited number of atoms, and the diameter of the cadmium selenide quantum dots is 0.2-900nm; the cadmium selenide quantum dots used are spherical three Three-dimensional system, cadmium selenide quantum dots also contain nanoparticles made of semiconductor materials composed of elements from IIB to VIA; liquid crystal materials can be smectic liquid crystals, cholesteric liquid crystals, and nematic liquid crystals; in liquid crystals Doping cadmium selenide quantum dots in the medium, mixing the prepared liquid crystal solution evenly, so that the cadmium selenide quantum dots are dissolved in the liquid crystal and reach a saturated state;

(2) Preparation of liquid crystal cell:

a. Use glass with a thin layer of ITO conductive film on one side as the ITO glass substrate, wipe the ITO glass piece with absorbent cotton in clean water, and then place the small piece of ITO glass in alcohol and pure water for 30 minutes. Above, after the ultrasound is over, take out the glass, put it in an oven and dry it, clean the ITO glass substrate, take out two clean ITO glass substrates, and evenly coat a layer with a concentration of not less than 0.01- The polyvinyl alcohol (PVA) organic solution of 2wt.% forms polyvinyl alcohol coating on ITO glass substrate, puts into baking oven again and drys, and the polyvinyl alcohol coating on ITO glass substrate surface is cured, then will A glass rod wrapped with lens cleaning paper rubs the ITO glass coated with polyvinyl alcohol 1 or 2 times in the same direction, which will form grooves;

b. Take out the two baked ITO glass substrates coated with polyvinyl alcohol, then overlap the conductive side of the ITO glass substrates coated with polyvinyl alcohol, and place the two ITO glass substrates along the The polyester film is placed between the two sides of the groove direction, and the thickness of the gap between the two ITO glass substrates is controlled to form a liquid crystal cell with a slit chamber structure. The purpose of inserting the polyester film is to provide a gap for the injection of materials later. Leave a suitable gap to facilitate the injection of the prepared material, which also determines the thickness of the material in the sample box;

(3) Preparation of holographic 3D display screen:

ⅰ. Using the holographic 3D display material mixed solution prepared in the step (1), take the supernatant of the holographic 3D display material mixed solution, and use the capillary drainage method to extract the supernatant of the holographic 3D display material mixed solution Fill in the slit chamber of the liquid crystal box prepared in the b step of said step (2) along the groove, in the liquid crystal box, due to the anisotropic characteristics of liquid crystal molecules, the tension effect between it and the glass surface makes The liquid crystal molecules in the first layer at the interface between liquid crystal and glass are arranged neatly in a specific direction to obtain liquid crystal micro-units;

ii. Combining a series of liquid crystal microunits prepared in the step i to form a cadmium selenide quantum dot-doped liquid crystal holographic 3D display.

In this embodiment, during the preparation process of the holographic 3D display screen, it is kept in a dry environment at room temperature.

Experimental test analysis:

The liquid crystal micro-unit prepared in this embodiment is placed at room temperature, voltage is applied across the liquid crystal micro-unit, and the measurement data of the two-wave coupling optical path in the diffraction reading is recorded by interference using the principle of holography. The object light and reference light in the optical path come from the laser, and the readout light comes from visible light. The laser is divided into the object light and the reference light by the beam splitter. The object light and the reference light interfere together on the sample with voltage applied. After reading with visible light, diffraction spots appear, and the interference recording angle is 2-4°.

The working principle diagram of this embodiment is shown in Figure 1. The holographic 3D display screen prepared in this embodiment is applied to a two-wave coupling optical path holographic 3D display system, which mainly includes two sets of lasers (1, 2), a set of half-wave Sheets (6, 8), dichroic prism 7, a group of mirrors (5, 9, 10, 11, 12), sample box 3 and receiving screen 4. The two-wave coupled optical path holographic 3D display system uses laser 1 as a laser to emit laser light, and laser 2 as visible light to emit light. After the laser passes through the half-wave plate 8, it is then divided into two beams of laser light by the beam splitter 7. The resulting two beams of laser light, One beam is the object light, the other beam is the reference light, and the object light passes through another half-wave plate 6. At this time, it is irradiated into the liquid crystal microunit together with the reference light, and the visible light is used as the readout light to directly irradiate the liquid crystal microunit. In this case, the three beams of light need to overlap to the same point of the liquid crystal micro-unit, and the spots diffracted by the readout light can be seen on the receiving screen 4, as shown in Figure 3, and the time curve for establishing the hologram is measured at this time as shown in FIG. The results shown in Figure 2(a) and the erasure time curve of the hologram in Figure 2(b), as shown in Figure 2,

This embodiment is based on the preparation of a holographic 3D display screen doped with cadmium selenide quantum dots and a liquid crystal material. According to a certain ratio, cadmium selenide quantum dots are mixed into the nematic liquid crystal to form a holographic material, and then the material is injected into two pieces of ITO glass to form a holographic 3D display. In this embodiment, cadmium selenide quantum dots are mixed with nematic liquid crystal to form a holographic material. The system selects object light and reference light from laser, and readout light from visible light. The dynamic response curve and diffraction efficiency of the material are measured by means of two-wave coupling.

In summary, this embodiment is a new material prepared by doping cadmium selenide quantum dots in the traditional holographic display liquid crystal, and makes the material have dynamic refresh characteristics in the holographic display system, which improves the diffraction efficiency. Reduced response time. The holographic display material prepared in this example provides a carrier for holographic true 3D display, and the prepared holographic 3D display screen can be widely used in the fields of hologram printing, holographic disc, real-time dynamic holographic display, and holographic photography.

Embodiment two:

This embodiment is basically the same as Embodiment 1, especially in that:

In this embodiment, a method for preparing a holographic 3D display screen with cadmium selenide quantum dots doped with a liquid crystal material comprises the following steps:

(1) Preparation of cadmium selenide quantum dot doped liquid crystal material:

When doping cadmium selenide quantum dots in liquid crystals to prepare holographic 3D display materials, according to the weight percentage calculation method, the doping weight ratio of cadmium selenide quantum dots is 0.01-10%, and the total weight of liquid crystals is 90-99.99%. Add quantum dots to liquid crystals to form a liquid crystal solution, place the obtained prepared liquid crystal solution in an oscillator to vibrate, mix well, and leave it for at least one day to obtain a quantum dot-doped liquid crystal holographic 3D display material mixture; Cadmium selenide quantum dots are composed of a limited number of atoms. The diameter of cadmium selenide quantum dots is 0.2-900nm; the cadmium selenide quantum dots used are spherical or rod-shaped three-dimensional systems. It also contains nanoparticles made of semiconductor materials composed of elements from IIIA to VA; the liquid crystal material can be smectic liquid crystal, cholesteric liquid crystal, and nematic liquid crystal; doping cadmium selenide quantum dots in the liquid crystal, Mix the prepared liquid crystal solution evenly, so that the cadmium selenide quantum dots are dissolved in the liquid crystal and reach a saturated state;

(2) Preparation of liquid crystal cell:

a. This step is the same as in Embodiment 1;

b. This step is the same as in Embodiment 1;

(3) Preparation of holographic 3D display screen:

ⅰ. This step is the same as Example 1;

ii. This step is the same as in Embodiment 1.

In this embodiment, during the preparation process of the holographic 3D display screen, it is kept in a dry environment at room temperature.

Experimental test analysis:

The sample box prepared in this embodiment was placed at room temperature, a voltage was applied across the sample, and the data was measured using the two-wave coupling optical path in the holographic principle. The object light and reference light in the optical path come from the laser, the readout light comes from the visible light, the laser is divided into the object light and the reference light by the beam splitting prism, and the object light and the reference light interfere together on the sample with voltage applied. Diffraction spots appear after reading with visible light.

In this embodiment, a new material is prepared by doping cadmium selenide quantum dots in the traditional holographic display liquid crystal, and makes the material have dynamic refresh characteristics in the holographic display system, which improves the diffraction efficiency and shortens the response time. The holographic display material prepared in this example provides a carrier for holographic true 3D display, and the prepared holographic 3D display screen can be widely used in the fields of hologram printing, holographic disc, real-time dynamic holographic display, and holographic photography.

Embodiment three:

This embodiment is basically the same as the previous embodiment, and the special features are:

In this example,

7. according to the preparation method of the holographic 3D display screen of the cadmium selenide quantum dot doped liquid crystal material described in claim 1 or 2, it is characterized in that: in the b step of described step (2), by adjusting the The thickness determines the thickness of the liquid crystal cell. In the b step of said step (2), take out two ITO glass substrates with polyvinyl alcohol coating that have been baked, then insert polyester film between the two ITO glass substrates, and control The thickness of the gap between two ITO glass substrates forms a liquid crystal cell with a slit chamber structure.

Experimental test analysis:

The sample box prepared in this embodiment was placed at room temperature, a voltage was applied across the sample, and the data was measured using the two-wave coupling optical path in the holographic principle. The object light and reference light in the optical path come from the laser, the readout light comes from the visible light, the laser is divided into the object light and the reference light by the beam splitting prism, and the object light and the reference light interfere together on the sample with voltage applied. Diffraction spots appear after reading with visible light. .

In this embodiment, a new material is prepared by doping cadmium selenide quantum dots in the traditional holographic display liquid crystal, and makes the material have dynamic refresh characteristics in the holographic display system, which improves the diffraction efficiency and shortens the response time. The holographic display material prepared in this example provides a carrier for holographic true 3D display, and the prepared holographic 3D display screen can be widely used in the fields of hologram printing, holographic disc, real-time dynamic holographic display, and holographic photography.

The embodiments of the present invention have been described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments, and various changes can also be made according to the purpose of the invention of the present invention. The changes, modifications, substitutions, combinations or simplifications should be equivalent replacement methods, as long as they meet the purpose of the present invention, as long as they do not deviate from the technology of the preparation method of the holographic 3D display screen of cadmium selenide quantum dot doped liquid crystal material Principles and inventive concepts all belong to the protection scope of the present invention.

Claims (6)

1. the preparation method of the holographic 3D display screens of a kind of CdSe quantum dots doped liquid crystal material, it is characterised in that including such as Lower step：

(1) preparation of CdSe quantum dots doped liquid crystal material：

When the CdSe quantum dots that adulterated in liquid crystal prepare holography 3D display screen materials, according to percentage by weight computational methods, selenium The doping part by weight of cadmium quantum dot is 0.01~10%, and liquid crystal gross weight is 90~99.99%, by CdSe quantum dots plus Liquid crystal solution is formed after entering liquid crystal, the liquid crystal solution for preparing for obtaining is well mixed, obtain quantum dot-doped liquid crystal hologram 3D display material mixed liquors.

(2) preparation of liquid crystal cell：

A. ito glass substrate is cut into as ito glass substrate using the glass with ITO conducting films for the size of setting, is passed through Over cleaning, ultrasound, baking link, purifying treatment is carried out by ito glass substrate, and clean ito glass substrate is taken out into two panels, The polyvinyl alcohol organic solution that mass percent concentration is not less than 0.01-2wt.% is uniformly coated with, forms poly- in ito glass substrate Vinyl alcohol coating, places into oven for baking, solidifies the polyethylene coating of ito glass substrate surface, and polyvinyl alcohol is applied Layer is oriented the treatment such as friction；

B. take out the ito glass substrate of the two panels handled well with polyethylene coating, then by two panels ito glass substrate it Between be encased inside mylar, and control gap thickness and differently- oriented directivity between two panels ito glass substrate, being formed has slit chamber structure Liquid crystal cell；

(3) preparation of holography 3D display screens：

I takes holographic 3D displays screen material mixing using the holographic 3D display materials mixed liquor prepared in the step (1) Liquid, using capillary drainage or other method, holographic 3D display materials mixed liquor is poured into and is made in the b step of the step (2) In the slit chamber of standby liquid crystal cell, liquid crystal micro unit is obtained；

II combines a series of liquid crystal micro units prepared in the step I to form the holography of CdSe quantum dots doped liquid crystal 3D display screens.

2. the preparation method of the holographic 3D display screens of CdSe quantum dots doped liquid crystal material according to claim 1, it is special Levy and be：In the step (1), institute is made up of using CdSe quantum dots a limited number of atom, CdSe quantum dots Greatest diametrical dimension be 0.2~900nm.

3. the preparation method of the holographic 3D display screens of CdSe quantum dots doped liquid crystal material according to claim 1 or claim 2, its It is characterised by：In the step (1), the CdSe quantum dots for being used are three spherical, spherical etc. dimension systems, selenizing The nano-particle being also made containing the semi-conducting material being made up of IIB~VI A or IIIA~VA element in cadmium quantum dot.

4. the preparation method of the holographic 3D display screens of CdSe quantum dots doped liquid crystal material according to claim 1 or claim 2, its It is characterised by：In the step (1), the material of liquid crystal can be smectic liquid crystal, cholesteric liquid crystal, nematic liquid crystal.

5. the preparation method of the holographic 3D display screens of CdSe quantum dots doped liquid crystal material according to claim 1 or claim 2, its It is characterised by：In the step (1), adulterate CdSe quantum dots in nematic liquid crystal, the liquid crystal solution mixing that will be prepared Uniformly, CdSe quantum dots is dissolved in nematic liquid crystal and reach saturation state.

6. the preparation method of the holographic 3D display screens of CdSe quantum dots doped liquid crystal material according to claim 1 or claim 2, its It is characterised by：In the b step of the step (2), the thickness of liquid crystal cell is determined by the thickness of adjusting gasket film.