Organic electroluminescent(EL) diodes have been extensively investigated. In this report, thin film multilayer structure utilizing organic dye(Alq_3) and hole transport material(TPD) has been fabricated by organic molecular beam deposition technique(OMBD). Organic EL diode has also been fabricated using the organic thin film multilayer structure. We found that the PL emission peak has been shifted to shorter wavelength as the layer thickness decreases. Spectral narrowing and the shift of peak emission wavelength have been observed in the EL diode with thin multilayer structure. Relation of EL intensity with the layer thickness has also been investigated.

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Newly synthesized azomethine-zinc complexes were examined as an emitting material in organic electroluminescence (EL) cells. Metal complexes sublimed in vacuum can be used for organic EL cells. Only inner complex salts were found to satisfy this condition. The inner complex salts of the azomethine-zinc complex were prepared by the reaction of zinc ion and ligands such as N-salicylidenealkylamine or N,N'-disalicylidene alkyldiamine. A cell structure of [ITO / hole transport layer / emitting layer / MgIn] was employed. The EL cell with (N,N'-disalicylidene-1.6-hexanediaminato)zinc(II) as an emitting layer showed a bright blue emission with an intensity of 1460 cd/m^2 for the first time as a complex emitting material. The emission peak was 450 nm.

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Liquid crystal displays (LCDs) have been widely used, because of their advantages of low power consumption, compactness and flatness. Above all, A/M LCDs, which supply excellent pictures, are expected to replace the conventional CRTs in near future. In this paper, some key properties of alignment layer for A/M LCDs Were reviewed. A study on the pretilt angle controllability of alignment layers, which are soluble in organic solvents, was reported. Some elaborate methods on treating alignment layers to develop LCD's view angle wide were also described.

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The light scattering (LS) profile of a (polymer/liquid crystal) solution during solvent evaporation, exhibited a periodic structure, indicating that the phase separated structure was formed by spinodal decomposition. The faster the solvent was evaporated, the smaller the LC channel (domain) size in the composite film was. The electro-optical behavior of the composite film was strongly depended on the LC channel (domain) size in the composite film. The transmittance increased. and also, the rise and decay response times, decreased and increased, respectively, with an increase in size of LC channel (domain). Also, was concluded that an interfacial mixing induced by dielectric loss energy was one of an important origin for a hysteresis in a electro-optical switching. When a low-frequency sinusoidal electric field is applied to LC molecules, the anchoring strength on the polymeric wall might be evaluated on the basis of the distortion of high-order response wave (odd-order non-linear dielectric property).

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The unique properties of LCPC such as high-response and scattering mode are enabling many applications like light-control window or non-mechanical shutter device. Recent development proved that LCPC is also a very promising display device which brings higher brightness than usual TN-LC device, for LCPC can be driven by TFT and hysteresis phenomenon problem,which was believed to be inevitable, was solved. In this report, the mechanism and the characteristic of LCPC are described as well as expected application of LCPC.

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The backlighting illuminair using the cold cathode fluorescent tube has been rapidly used for the light source of the graphic LCDs. Recently the full-colored TFT-LCD using the personal computer needs the illuminace of above 100 cd/m^2 for fine and bright visualizations. The illuminance of backlighting illuminair is increased by arranging the prasmatic-lens film on the illuminair. We investigated the relationship between the brightness and the viewing angle characteristics of the backliting illuminair and the angle of the prasmatic-lens film. It was the most brightness when the angle of prism is near 90°.

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