Abstract: The method for orientation of liquid crystals in a micro/nano region on the basis of laser direct writing and a system thereof includes a laser direct writing system employed to build a micro/nano structure. Liquid crystal molecules in a micro/nano structural region perform self-orientation; and the orientation of liquid crystals is generated by fine structures on side walls of polymer strips which form the micro/nano structure. The dimension of the micro/nano region varies from the micrometer magnitude to the nanometer magnitude exceeding the diffraction limit. The orientating direction can be adjusted and controlled in the micro/nano region, which is favorable for the miniaturization of the liquid crystal display devices and the orientation of the complicated three-dimensional liquid crystal structure.

Abstract: A bismuth and magnesium co-doped lithium niobate crystal includes Li2CO3, Nb2O5, Bi2O3 and MgO, wherein the molar ratio of [Li] and [Nb] is 0.90-1.00, the molar percentage of Bi2O3 in the mixture is 0.25-0.80%, and the molar percentage of MgO in the mixture is 3.0-7.0%. The bismuth and magnesium co-doped lithium niobate crystal has enhanced photorefraction, improved photorefractive sensitivity, shortened holographic grating saturation writing time, and the photorefractive diffraction efficiency can reach up to 17%. The response time is only 170 ms, when the holographic storage experiment is carried out using 488 nm continuous laser. Therefore, this crystal can be used in the field of holographic imaging.

Abstract: A bismuth and magnesium co-doped lithium niobate crystal includes Li2CO3, Nb2O5, Bi2O3 and MgO, wherein the molar ratio of [Li] and [Nb] is 0.90-1.00, the molar percentage of Bi2O3 in the mixture is 0.25-0.80%, and the molar percentage of MgO in the mixture is 3.0-7.0%. The bismuth and magnesium co-doped lithium niobate crystal has enhanced photorefraction, improved photorefractive sensitivity, shortened holographic grating saturation writing time, and the photorefractive diffraction efficiency can reach up to 17%. The response time is only 170 ms, when the holographic storage experiment is carried out using 488 nm continuous laser. Therefore, this crystal can be used in the field of holographic imaging.

Abstract: The method for orientation of liquid crystals in a micro/nano region on the basis of laser direct writing and a system thereof includes a laser direct writing system employed to build a micro/nano structure. Liquid crystal molecules in a micro/nano structural region perform self-orientation; and the orientation of liquid crystals is generated by fine structures on side walls of polymer strips which form the micro/nano structure. The dimension of the micro/nano region varies from the micrometer magnitude to the nanometer magnitude exceeding the diffraction limit. The orientating direction can be adjusted and controlled in the micro/nano region, which is favorable for the miniaturization of the liquid crystal display devices and the orientation of the complicated three-dimensional liquid crystal structure.

Abstract: This invention relates to the field of materials of the photorefractive crystal. The composition of these crystals is Li1−xNb1+yO3: Fem, Mn, where M can be magnesium, indium, or zinc; when using q to denote the ion valence of M (q=2 when M is Mg or Zn, and q=3 when M is In), the values of x, y, m, and n are in the range of 0.05≦x≦0.13, 0.00≦y≦0.01, 5.0×10−5≦m≦7.5×10−4, and 0.02≦qn≦0.13. This invention greatly improves the photorefractive properties of LiNbO3 crystals: makes it have a high diffraction efficiency (more than 68%), a fast response speed for photorefraction (an order of magnitude faster than iron doped LiNbO3), and a high resistance to optical scattering (the light intensity threshold to photorefractive fan scattering near two orders of magnitude larger than LiNbO3: Fe). This invention is an excellent three-dimensional optical storage material and has a vast potential market.

Abstract: The invention relates to the information storage. It consists of a computer, a precise rotary table, a writing laser source, a readout laser source, a spatial filter, a spatial light modulator, lens, mirrors, photorefractive crystals (such as doubly doped lithium niobate), and a phase-mismatch adjustor; Due to used a green light (532 nm) as the writing light, and a red light (670 nm) as the readout light, the signal-to-noise ratio is improved greatly and the problem of fixing the stored information is solved. The transmission configuration is used to realize the high-density digital storage in which the irregular lens is designed to work as a phase-mismatch adjustor and read out the whole stored image with no distortion and loss. The dynamically differential encoding and decoding technique is used to suppress the bit-error-rate to lower than 10−6.

Abstract: The invention relates to the information storage. It consists of a computer, a precise rotary table, a writing laser source, a readout laser source, a spatial filter, a spatial light modulator, lens, mirrors, photorefractive crystals (such as doubly doped lithium niobate), and a phase-mismatch adjustor; Due to used a green light (532 nm) as the writing light, and a red light (670 mn) as the readout light, the signal-to-noise ratio is improved greatly and the problem of fixing the stored information is solved. The transmission configuration is used to realize the high-density digital storage in which the irregular lens is designed to work as a phase-mismatch adjustor and read out the whole stored image with no distortion and loss. The dynamically differential encoding and decoding technique is used to suppress the bit-error-rate to lower than 10−6.

Abstract: This invention relates to the field of materials of the photorefractive crystal. The composition of these crystals is Li1−xNb1+yO3: Fem, Mn, where M can be magnesium, indium, or zinc; when using q to denote the ion valence of M (q=2 when M is Mg or Zn, and q=3 when M is In), the values of x, y, m, and n are in the range of 0.05≦x≦0.13, 0.00≦y≦0.01, 5.0×10−5≦m≦7.5×10−4, and 0.02≦qn≦0.13. This invention greatly improves the photorefractive properties of LiNbO3 crystals: makes it have a high diffraction efficiency (more than 68%), a fast response speed for photorefraction (an order of magnitude faster than iron doped LiNbO3), and a high resistance to optical scattering (the light intensity threshold to photorefractive fan scattering near two orders of magnitude larger than LiNbO3: Fe). This invention is an excellent three-dimensional optical storage material and has a vast potential market.