Among the methods to measure the pretilt angle in a liquid crystal cell being aligned homogeneously, the crystal rotation method is commonly used because it is very precise and it requires a short time to measure. But when the cell gap of test cell is not uniform, the cell gap changes during the measurement because the measurement point is shifting. This shift is caused by refraction at the glass of the cell. Therefore the measured pretilt angle by this method can contain a significant error. In this paper, we estimate the magnitude of this error theoretically and experimentally. We propose it new improved crystal rotation method. By this method an accurate value can be obtained even if the cell gap is not uniform.

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We study the dynamical evolution of the characteristics of transmission of polarized light through liquid crystal display pannels according to the voltages applied to the pannels.

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Effects of the photo-induced optical anisotropy of azo dye-doped polymer films on azimuthal alignment of a liquid crystal have been dynamically investigated using linearly polarized pumping and probing beams. The results show that the azo dye-doped polymer films memorizes the information on the polarization direction of the pumping laser beam and the resulting anisotropy induced in the films causes adjacent liquid crystal molecules on the film to rotate azimuthally.

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The mechanism of liquid crystal alignment on a rubbed surface is not yet perfectly under-stood. Therefore, authors have measured the surface shape of rubbed alignment layers and of morphology stamped surface using atomic force microscopy. Using the elastic continuum theory, we made a quantitative evaluation of the azimuthal surface anchoring energy due to the distortion of the surface shape. We compared the experimental value to the calculated value. In the case of a morphology stamped substrate, both values are similar. However, in the case of a rubbed substrate, the azimuthal surface anchoring energy obtained by theoretical calculation is more than two orders of magnitude smaller than the one obtained by experiment. From these results, we conclude that the alignment of liquid crystals on rubbed surface depends on other effects rather than on surface morphology effect.

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The Langmuir-Blodgett (LB) method have been widely utilized to prepare ultra-thin organic films for electronic device applications. It have been recognized that characterization of LB films were difficult because of its ultra-thin thickness. Therefore, although several reports on the ability of LB films for aligning liquid crystals were published, a detailed characterization of the films was not done. We succeed i1n measuring the torsional anchoring strength between LB films and liquid crystals using the one-side rubbing cell. The torsional anchoring strength between the polyimide LB films and 5CB is estimated to be 3.2×10^<-6> [N/m].

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The red-color electroluminescent devices consisting of CaS:Eu layers were fabricated by utilizing the rf-sputtering technology. The electrical and luminescent properties were studied in an ac-pulse excitation mode in order to clarify the effect of Cu co-dopant in a sputtering target and H_2S in a sputtering gas. The experimental results have shown that the Cu co-dopant increases the amount of transfered charge through the active layer and the H_2S incorporation in the sputtering gas improves the buildup waveform of light waveform.

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A new target structure of ZnS:TbOF-Al_2O_3-backing plate is proposed. In this doubly-layered sputtering target completely avoids the particle contamination when using the pressed sputtering target. A systematic study on preparation conditions such as TbOF content in the target, rf-power, gas pressure, substrate temperature, and post-annealing temperature was made to improve the performance of green-emitting ZnS:TbOF TFEL devices. A developed device in this work typically shows the luminance exceeding 120 cd/m^2 at V_<th>+30 V with a frequency of 60Hz.

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We arrayed leaky fused-quartz lightguides, each illuminated by GaAlAs light-emitting diodes, to make a row-addressable backlight. It was much more efficient than a dc-plasma row-backlight that we made also. Test patterns were displayed by operating the backlight with a ferroelectric liquid-crystal shutter array, and gray-scale capability was demonstrated.

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Plasma display panels (PDPs) are the most suitable to large-area and full-color display. PDPs are expected for wall-hanging displays for high definition TV. For full-color PDPs, the information about ultraviolet rays emission is especially important, because ultraviolet rays are made use of exciting the phosphors. Ne+xe gas was used for working gas and we measured about spectra emitted from the states concerning ultraviolet rays emission.

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This paper consists of structural reformation of the panel to solve the specific characteristics of low brightness in conventional color PDP. Installation of auxiliary electrode and then selecting pulse memory driving method is widely known as the most desirable way for PDP.^<[1.2.3]> In this experientment, unlike the existing panel structure, we've studied and surveyed the special character of installation of auxiliary electrode on top of the 1^<st> Barrier Rib. In this selection of structure, resolution is improved as cell pitch of panel is decreased, at the same time improves the brightness by the effect of memory.

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A color PDP having fine and uniform cells was fabricated using a metal-mesh partition coated with a glass layer. The partition not only eliminates a use of thick-film barrier ribs, but surves as a trigger electrode of the panel. By providing a trigger discharge, stable display discharge were obtained with a reduction of working voltage by 50 volts. Also the use of a new cathode material, LaNiO_3+Li_2O, provided an additional reduction of the voltage. Black matrix coated on the partition sheet provided a high contrast display.

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We have made a numerical analysis of the micro-discharge in plasma display panel using 2-dimensional multi-fluid equations. The plasma gas is Ne + Ar 0.1% gas in a state of non-LTE glow. We obtained the distributions of the microscopic variables such as the density, temperature, velocity of ion and electron. We also found the distributions of excited species during glow and after glow. From the simulation result, the non-discharge pulse applied to the auxiliary anode affect the distribution of ion density, meta-stable density and other excited species considerably. We have also found that the optimization of the frequency and voltage of the discharge pulse could improve the efficiency of the DC memory PDP.

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Impressive Hi-Vision (HDTV: High-definition TV) pictures have been reproduced on 33-inch and 40-inch color DC plasma displays. This success was due to the development of the fabrication of large-area color DC PDPs, pulse memory drive technique, and signal processing. This paper describes the fabrication process --mainly thick-film printing and phosphor deposition-- for large-area color DC PDPs, developed to make Hi-Vision flat receivers.

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In this paper we present an ac plasma display adopting new structure that seperates the addressing and sustain operations to operate not only the vertical data but also the horizontal scanning with high impedance driver. In our 4-electrode type methods, the sustain electrodes and scanning electrodes are acting as capacitive coupling. The scanning driver consists of open drain and the sustain operation is made by the seperated sustain driver. We believe that the high impedance driver IC can be used as not only the vertical data driver but also the horizontal scanning driver and the whole panel can be operated by one pair of output from sustain driver.

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