58results about How to "Improve electro-optic performance" patented technology

The invention in particular relates to a preparation method of polymer dispersing liquid crystal film by an ultraviolet irradiating-heating plus stepwise initiated polymerization and phase separation method, belonging to the functional material field, which is applied in the preparation of electric controlled intelligent glass. The preparation method is characterized in that: the nematic liquid crystal, the monomer which can be polymerized under ultraviolet light, the light initiator, the thermal polymerized monomer and the glass microsphere is blended and then are clipped between two pieces of transparent conductive film plated with indium tin oxide, and then film with the thickness of 20 Mum if formed and is irradiated by the ultraviolet light with the wavelength of 365nm at 0 to 25 degrees; the intensity of the ultraviolet light is 20.0mW/m<2> and the illumination time is 1 to 10 minutes; the thermal polymerization temperature is 60 to 100 degrees, the holding time is 5 to 8 hours, at last the PDLC film is prepared by solidification. The polymer dispersing liquid crystal film has the advantages that: because of the stepwise polymerization crosslinking reaction which is carried out by selecting the monomer polymerized by ultraviolet and thermal polymerized monomer and irradiating and heating under ultraviolet light, the electro-optic performance the PDLC film is improved, the network strength of the polymer is enhanced, meanwhile, the bonding force of the interface between the polymer network and the ITO film are reinforced.

The invention specifically relates to a secondary electro-optic crystal with a gradient refractive index effect as well as a preparation method and an application method of the secondary electro-optic crystal. The secondary electro-optic crystal is an ion doped electro-optic crystal with a general formula of M: KTa[1-x]NbxO3, and has a perovskite structure, wherein M=Cu<2+>, Fe<3+>, Sn<4+>, Ni<2+>, Ti<4+>, Na<+> and Li<+>, and the content of M is 0-5at%; the content x of Nb in a crystal component is more than or equal to 0 and less than or equal to 5, a curie point is positioned between -241 and 90 DEG C, the crystal above the curie point is a cubic phase and an m3m point group; and the crystal below the curie point becomes a tetragonal phase and a 4mm point group, a matrix component Ta/Nb is uniformly distributed in the crystal, doped ions M are in non-uniform distribution in the crystal, and the concentration distribution changes linearly along the growth direction of the crystal. The invention realizes functional combination of an electro-optic effect and a gradient refractive index effect of the crystal, and respectively realizes modulation of propagation direction and intensity of laser in different directions of the same modulation sample.

Polymer network liquid crystal materials have improved mechanical properties such as rigidity and hardness and substantially improved electro-optical performance. The PNLC material can be manufactured with an emulsion process so as to simplify substantially the manufacturing process. Each LC droplet can be configured with the polymer network extending substantially across the LC droplet, and the polymer network may comprise a material to lower substantially the switching voltage, such as a fluorinated acrylate that may interact with the liquid crystal so as to lower the surface tension of the LC droplet. The PNLC material may comprise an interfacial layer combined with the polymer network so as to decrease substantially the driving voltage.

A polymer-dispersed blue-phase (PDBP) liquid crystal film is formed from a polymer-based latex and blue-phase liquid crystals that are combined using an emulsification process or a polymerization-induced phase separation process. The resultant PDBP liquid crystal film includes droplets formed by the polymer-based latex that encapsulate the blue-phase liquid crystals therein, so as to allow the blue-phase liquid crystals to have a blue phase at room temperature. As such, the PDBP liquid crystal film is conducive for use in manufacturing processes, such as LCD (liquid crystal display) manufacturing processes, while providing desirable optical features, such as field-induced birefringence at low switching voltages.

The invention discloses a method for enhancing the electro-optical performance of liquid crystals by Cu2O nano-particles and belongs to the technical field of liquid crystal display. The method is characterized in that Cu2O nano mesoporous spheres and Cu2O nanospheres of the same size are doped with cholesteric liquid crystals N*-LCs at the mass fraction of 0.10-0.50% to form a nano material and liquid crystal compound, Cu2O MPS and Cu2O NS of the same size are doped with nematic liquid crystals 5CB at the mass fraction of 0.001-0.200% to form a nano material and liquid crystal compound, and prepared liquid crystal baths are adopted for electro-optical performance test. As a small quantity of Cu2O nano material is doped with the liquid crystals, the driving voltage of both the cholesteric liquid crystals and the nematic liquid crystals can be greatly reduced, and the voltage decreasing amplitude of the liquid crystals doped with the mesoporous spheres is larger than that of the liquid crystals doped with the nanospheres.

The invention relates to the field of organic second-order nonlinear optical materials and especially relates to an organic second-order nonlinear optical chromophore which has a D-pi-A structure and utilizes julolidine or its derivative as an electron donor, a thiophene ring or a cyclic polyene structure as a conjugate electron bridge and tricyano-dihydro furan or trifluoro-substituted tricyano-dihydro furan as an electron acceptor, and its synthesis method and use. Through combination of the used electron donor, conjugate pi electron bridge and electron acceptor, the organic second-order nonlinear optical chromophore can improve an intramolecular electron transfer capability and improve intermolecular steric hindrance. The organic second-order nonlinear optical chromophore can effectively improve a chromophore molecule first-order hyperpolarization rate (beta) and can effectively reduce intermolecular interaction. The organic second-order nonlinear optical chromophore adopted with amorphous polycarbonate can be used for preparation of a polarized polymer film. The polarized polymer film can be used as a material in the optical signal modulation field. The organic second-order nonlinear optical chromophore has a structure shown in the following description.

The invention provides a preparation method of a light modulation film based on a liquid crystal/polymer composite material. The method comprises the following steps that: after a liquid crystal, a photopolymerizable monomer and a photoinitiator are uniformly mixed according to a certain mass ratio, the mixture is in a clear state at a room temperature; on the basis of the siphon principle, the mixture is poured into a liquid crystal box, wherein the thickness of the liquid crystal box is controlled between 10 to 30 microns by a plastic spacer; irradiation under the ultraviolet light having the light intensity of 5 to 25 mw/cm<2> and the wavelength of 365 nm is performed for 5 to 20 minutes at a room temperature, so that a polymer dispersed liquid crystal film is formed. According to the invention, with introduction of the functional thiol monomer, the refractive index is high, the water resistance performance is excellent, the heat insulation effect is good, the oxidation resistance performance is excellent, the initiator amount is small, and the photoelectric property of the prepared PDLC film is improved substantially. Moreover, the size of the polymer mesh and the size of the liquid crystal droplet are adjusted by adjusting the mass ratio of acrylate to thiol to liquid crystal. The prepared polymer dispersed liquid crystal film has advantages of small driving voltage, highcontrast, and stable performance.

The invention discloses a preparation method of a polymer dispersed liquid crystal (PDLC) membrane material and the prepared PDLC membrane. The preparation method comprises the steps that polymerizable monomers and a liquid crystal material are mixed according to the mass ratio of (3:7) to (7:3), and an ultraviolet initiating agent is added, wherein the ultraviolet initiating agent accounts for 3-5% of the total mass of the polymerizable monomers, and the adopted liquid crystal material is matched with the selected polymerizable monomers in refractive index; and a mixture is poured into a liquid crystal cell and irradiated under ultraviolet light, and thus the PDLC membrane is prepared. The adopted polymerizable monomers are not prone to volatizing, low in toxicity and small in irritation;a system is high in stability and easy to preserve; through a polymerization crosslinking reaction of ultraviolet light and acrylate and mercaptan monomers, a formed polymer matrix has a unique composite structure, namely, the composite structure is provided with the dense surface and a hole-type internal structure with attached microspheres, the polymer matrix is good in toughness, fast in deformation recovery and good in stability, the electro-optical performance of the PDLC membrane is greatly improved, and thus the PDLC membrane has the lower driving voltage, the high response speed and the high contrast.

The invention relates to the organic second-order nonlinear optical material field, and especially relates to an organic second-order nonlinear optical chromophore having a D-pi-A structure, and a synthetic method and a use thereof, wherein the organic second-order nonlinear optical chromophore is prepared through treating a 1,1,7,7-tetramethyljulolidine derivative as an electron donor and tricyanodihydrofuran or tricyanopyrroline as an electron acceptor. The alkyl group on the julolidine donor N used in the synthetic method and a phenyl ring form a closed six-membered ring, and the upper surface and the lower surface of the six-membered ring are respectively connected with a methyl group, so the spatial steric hindrance structure can effectively reduce the interaction force among molecules and improve the first-order molecular hyperpolarizability (beta) of the molecules of the chromophore. The organic second-order nonlinear optical chromophore having the D-pi-A structure can be doped with an amorphous polycarbonate to prepare a polarized polymer film, and the prepared film can be used as a material in the optical signal modulation field. The structures of the organic second-order nonlinear optical chromophore are represented by formulas in the specification.

The invention discloses on-chip cascaded MZI reconfigurable quantum network architecture based on lithium niobate. The on-chip cascaded MZI reconfigurable quantum network architecture comprises an input waveguide array serving as a neural network input layer, a plurality of MZIs which are optically connected with the input waveguide array and serve as a neural network hidden layer, a saturable absorber array, a nonlinear optical unit and a detector array serving as a neural network output layer. The MZIs are connected with each other and linearly converted into second array optical signals according to the first array optical signals; each saturable absorber in the saturable absorber array receives a corresponding optical signal in the second array optical signal and nonlinearly converts the optical signal into a third array optical signal, and the third array optical signal is detected by the detector array. According to the invention, the technical problem of on-chip coherent opticalneuromorphic calculation based on a photon integrated circuit is solved, and the limitation of calculation efficiency and power consumption in micro-electronic and hybrid optical electronic implementation is eliminated by a universal and reconfigurable quantum optical neural network.

The invention provides a preparation method of a polymer dispersed liquid crystal film, is applied to preparation of electronic control intelligent glass and belongs to the field of liquid crystal material application. The method comprises the steps of: uniformly mixing thermal polymerizable monomers, curing agents, nematic liquid crystal and glass microbeads in certain mass ratio; subsequently clamping the mixture between two conductive films plated with indium tin oxide at the temperature 0.5-20.0 DEG C higher than the clearing temperature of the liquid crystal phase of the thermal polymerizable monomers/curing agents/liquid crystal composite materials; compressing with a roll shaft uniformly so as to form a film layer of 10.0-15.0 microns in thickness; heating for 5.0-7.0 hours at 70.0-90.0 DEG C; and finally curing so as to form the polymer dispersed liquid crystal film. The preparation method provided by the invention has the advantages that the thermal stability of a polymer network is enhanced; the flexibility of a PDLC (Polymer Dispersed Liquid Crystal) film is improved; and the mesh size of a macromolecule network is regulated by selecting the optimal ratio of two monomers, so that the purpose of improving the thermal stability and contrast ratio of polymer dispersed liquid crystal film materials and the binding force between the macromolecule network and an ITO (Indium-Tin Oxide) film is reached.

A liquid crystal electrooptical element comprises a pair of substrates (20, 21) positioned between a pair of polarising plates, electrodes defining pixel areas (1) and alignment layers disposed on the respective opposing inside surfaces of said substrates (20, 21) and a chiral nematic liquid crystal sandwiched between said pair of surfaces. At least one of the alignment layers is patterned in such a way that the azimuth or pretilt or both alignment directions (14 to 17, 16 to 18) are different at the substrate interfaces suppressing the growth of the ground state of the liquid crystal. When an initial electrical pulse is applied, one of the at least two bistable states is reached, wherein the contrast ratio between said bistable states is two or greater. A device with these elements is long-term bistable and does not require electronic refreshing as long as the displayed information is not changed. Therefore, the power consumption of this bistable device is minimal.

The active region of a long-wavelength light emitting device is made by providing an organometallic vapor phase epitaxy (OMVPE) reactor, placing a substrate wafer capable of supporting growth of indium gallium arsenide nitride in the reactor, supplying a Group III–V precursor mixture comprising an arsenic precursor, a nitrogen precursor, a gallium precursor, an indium precursor and a carrier gas to the reactor and pressurizing the reactor to a sub-atmospheric elevated growth pressure no higher than that at which a layer of indium gallium arsenide layer having a nitrogen fraction commensurate with light emission at a wavelength longer than 1.2 μm is deposited over the substrate wafer.

The invention discloses a preparation method of a polymer dispersed liquid crystal film. The preparation method comprises the steps of S1, mixing the following raw materials in percentage by mass to obtain a liquid crystal mixed solution: 30-80% of a liquid crystal material, 5-50% of a thiol monomer, 5-50% of an acrylate monomer, 5-50% of an alkene polymerizable monomer, 0-15% of a cross-linking agent and 0-10% of a photoinitiator; S2, taking two transparent substrates coated with a conductive ITO coating, andoppositely arranging the surfaces with the conductive ITO coating to form a liquid crystal box; S3, pouring the prepared liquid crystal mixed solution into the liquid crystal box, and solidifying the liquid crystal mixed solution through polymerization reaction; and S4, respectively connecting the conductive ITO coatings of the two transparent substrates with two electrodes of a power supply assembly. According to the preparation method of the polymer dispersed liquid crystal film, liquid crystal molecules are converted into an isotropic state on the basis of a polymerization reaction of thiol-alkene monomers, and the finally prepared polymer dispersed liquid crystal film is excellent in mechanical property, good in electro-optical property and longer in service life.

The performance of an electro-optic display, for example, a bistable electro-optic display, can be improved by modifying the frame rate of a base waveform used to drive a transition between gray states. Such modifications permit fine control of gray levels with reduced artifacts. The described methods additionally require less memory to store all of the waveforms needed to achieve good performance of an electro-optic display over a range of temperatures.

The invention belongs to the technical field of functional materials and preparation thereof, and relates to an organic nonlinear optical crystal material DOBT and a preparation method thereof. The method comprises the following steps: firstly, preparing methyl p-toluenesulfonate and 2-methylbenzothiazole solutions with equal molar weight by taking methanol as a solvent, and then mixing the two prepared solutions for reaction; adding 3,4-dimethoxybenzaldehyde with equal molar weight, and adding a catalyst for reaction to obtain a crystal growth raw material; and then carrying out DOBT crystal growth by adopting a spontaneous nucleation method. The obtained crystal belongs to a nonlinear optical crystal, and molecules with benzothiazole rings are contained in the structure, so that the non-centrosymmetric degree of the crystal is further improved, and the generation of a relatively large second-order nonlinear optical coefficient is facilitated; the second-order nonlinear optical property of the material is about 6 times that of KDP, and the material also has good electro-optical performance. The preparation method of the crystal is simple and convenient, the nonlinear performance is better, and the crystal has a higher application prospect.

The invention discloses an inverted structure OLED device based on a strong electron injection layer and a manufacturing method thereof. The inverted structure OLED device comprises an ITO transparentcathode, a strong electron injection layer, a BPhen electron transport layer, a TAZ light-emitting layer, a CBP hole transport layer, a molybdenum trioxide hole injection layer and an Al anode from left to right. The strong electron injection layer comprises one or two of a zinc oxide layer and a cesium carbonate layer or a zinc oxide-cesium carbonate layer. The manufacturing method comprises thesteps of preparation of a cesium carbonate-ethanol solution and a zinc oxide-methanol solution, preparation of a mixed solution, treatment of the ITO transparent cathode and preparation of the inverted-structure OLED device. In the invention, cesium carbonate and zinc oxide are preferably selected to be compounded so as to serve as the strong electron injection layer; based on a TAZ light emitting layer, the OLED device shows excellent short wavelength emission, a maximum radiance is 2.42 mW/cm<2>, EQE is 0.85%, working durability is improved, and XPS analysis shows that s-ZnO+Cs2CO3 shows excellent electronic performance and is beneficial to electron injection so that electro-optical performance of the OLED device with the inverted structure is improved.

The invention discloses an organic second-order nonlinear optical chromophore, a synthetic method and an application. The organic second-order nonlinear optical chromophore is provided with a structure of a Formula (CL) or Formula (HCL): FORMULA, wherein G is H, para-alkoxyphenyl, thienyl, or para-dialkyl aminophenyl; R1 is alkyl, benzyl, and halogenated alkyl; R2 is methyl or trifluoromethyl; R3 is alkyl, phenyl, replaced phenyl, replaced thienyl or hydroxyalkyl. The organic second-order nonlinear optical chromophore with D-Pi-A structure has simple synthetic step and high preparation yield; besides, it has good solubility in the most organic solvent and high thermal stability; the organic second-order nonlinear optical chromophore can be widely applied to the field of optical information material.