Conventional Single-Hybrid Aligned Nematic Liquid Crystal Displays (S-HAN-LCDs) have a strong viewing angle dependence in the plane containing LC directors. In order to improve the viewing zone, we propose a dual-domain structure of Hybrid Aligned Nematic Liquid Crystal Displays (D-HAN-LCDs), and the electrooptical performance of the D-HAN-LCDs is investigated by a computer simulation. From the simulation, it is shown that the viewing angle characteristics are symmetrized and the viewing zone of the D-HAN-LCD is widen by using a uniaxial retardation films.

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A Langmuir Blodgett (LB) method is one of rubbing-free technique to align Liquid Crystals (LCs) and thus attracts people's interests. In this study, we have studied LC alignment effects on Poly Di-isopropyl fumarate (PDiPF) prepared using LB method due to its simpler process than the preparation of Polyimide (PI)-LB films. We characterize LC alignment capability of the PDiPF-LB film by measuring the order parameter and the azimuthal anchoring energy. As results of these measurements, we confirm that the order parameter of a PDiPF-LB film sample reaches about 95% that of a rubbed PI sample and the value of azimuthal anchoring energy of a PDiPF-LB sample is more than 10^<-5> [J/m^2], this value correspond to that of PI-LB film that is deposited under the optimum conditions.

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The influence of the emission site on the running durability of organic electroluminescent devices was examined. The fundamental device structure of [MgIn/BeBq_2/TPD/MTDATA/ITO] was employed. The dopant (rubrene) was doped in the TPD layer of device A and in the BeBq_2 layer of device B. The device C was non-doped device. The running lifetimes of devices A, B and C, in which the initial luminance was reduced to one-half under a constant driving current (5mA/cm^2), were 3554 h, 289 h, and 23 h, respectively. It was thus found that the emission site exerts an influence on the running durability.

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Conducting polymers such as polypyrrole arc expected to utilize as electrochromic devices, because they change in their electrical conductivity and absorption of light, corresponding to doping and undoping of ions. However, it has been difficult to fit them for practical use, because these polymers are mechanically hard and brittle and they have only a short cycle-life when used repeatedly. To overcome these defects and to improve their practical performance, we developed a new method of conducting polymer films of good durability ; composite films of Polypyrrole (PPy) and the Poly vinyl-alcohol (PVA). By using this PPy/PVA composite, we developed a solid-state device of electrochromic display. The device showed color change (black & transparent yellow) more than 10^5 times under repeated and alternate application of DC voltages of ±0.9.

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Photon-Mode Superrsolution Reading of optical ROM disks is demonstrated. Saturable absorbing layer made of a derivative of Si-naphthalocyanine dispersed in polymer matrix is deposited on the signal recorded surface. A carrier recorded with a spatial frequency of 1670 mm^<-1> over the diffraction limit of the optical pickup system, 1360 mm<-1>, can be read out with a carrier to noise ratio (CNR) of 45 dB. EFM signals with a double recording density compare to the conventional Compact Disc can also be read out. These demonstrate a practical applicability of photon-mode superresolution using organic dye absorbers.

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