The survey of a stray emission source in CRT is difficult. One of the reasons is that the potential distribution between an electron gun and a tube neck is not well known because of the complicate structure of the electron gun. The potential distribution on the surface of a tube neck and bead glass are calculated by using Hybrid infinitive element method with 2D model, and the origin of a stray emission source is studied.

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We have developed and launched on the market a high-quality color picture tube called SUPERBRIGHTRON_<TM>. which is equipped with two types of color filters (both filtering layers internal and exteral) for the first time in the world. The internal filter consists of blue, green and red filters formed between the corresponding color-emitting phosphors and the face glass, which the external filter is a selective-absorption filter formed on the outside of the face glass. These filters achieve remarkable improvements in contrast and color gamut by absorbing a large amount of the ambient light with little reduction in brightness, and by selectively absorbing the sub-band portions of the light emitted by the phosphors. Improvements in contrast of 36% and 74% and in color gamut of 7% and 12%. against external filter tube and without any filtering layers tube, have been obtained with this picture tube.

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At present, the market of CDT (Color Display Tube) requires a cast and power saving characteristics. Therefore, we have introduced a mini neck (φ22.5mm) CDT design concept. However, this mini neck design gives a smaller electron main lens in its electron gun, which result in the focus degradation. As one of the most effective solutions for this problems, we have introdeuced a new dynamic focus electron gun system, DAQ (Dynamically Activated Quadrupole lens). Furthermore, we have developed a power and resource saving new Deflection Yoke (DY) by means of a optimum arrangement of a main coil and VCR coil and also by a cutting down of DY elements such as a VLMF compensating coil etc. In addition, we have designed a new inner shield in order to reduce the beam displacements in the terrestrial magnetic field.

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We have developed a high-performance electron gun for color monitor CRTs to be used with an increased deflection angle over the current standard of 90° for shortening the tube. To improve a deterioration in spot-uniformity over the screen which takes place with increasing deflection angle, the quadrupole lens for the dynamic focus of the DQ-DAF gun is enhanced by a new design of the lens. In addition, a new G1 quadrupole and a reduced focus-voltage-ratio of 24% are introduced. With this gun the spot performance of a 100° deflection tube is equivalent to that of the 90° tube.

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Circuit model of thin film EL display panels for SPICE simulation has been discussed. To reduce the number of circuit elements, macro-pixel elements were used for modeling of the EL panels. SCR switch in Row driver IC's was also included for the simulation model. From predicted voltage wave forms, computed by SPICE, for a first pixel and an end pixel of each Row line, it has been shown that the maximum farm frequency of the EL panel was restricted by the resistance of the Row electrode and internal resistance of SCR switch.

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New driving method has been developed to improve the luminance of EL panels. This method uses additional pulses, which are added to symmetric drive pulses in the every field of Push-Pull driving method. Increase of the luminance due to the additional pulses results from the polarization charge generated by driving pulses. It has been confirmed that the luminance of ZnS : Mn thin film EL devices was increased by using the driving pulse waveforms, which simulated the new driving method. We have also examined this method for 9inch diagonal, 640×400 ZnS : Mn thin film EL panels.

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Newly synthesized four diamine derevatives as hole transport layer were investigated in order to improve the durability of organic electroluminescent devices and have sutdied the difference of characteristics between newly synthesized derivatives and TPD. We obtained devices by using TPD2 and TPD3 which are higher luminous efficiency than device using TPD. Glass transition temperature of TPD4 is higher than that of TPD.

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Optical and electroluminescent properties of rubbing-aligned conducting polymers such as poly (2,5-dinonyloxy-p-phenylenevinylene), poly (3-alkylthiophene)s, and poly (p-phenylenevinylene) were studied. Polarized electroluminescence with dichroic ratio of 4 which was substantially the same as that of the photoluminescence was observed from EL devices composed of the rubbing-aligned polymer layer and an electron-transporting layer.

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Recently, organic electroluminescent (EL) devices have been extensively investigated. In this report, the fabrication of EL device with thin film of conducting polymers containing organic dye molecules or fullerene have been reported, and their electroluminescent characteristics have been discussed. By doping the conducting polymers with the molecules, color variability, emission quenching phenomenon and emission enhancement effect have been found in their electroluminescent characteristics.

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Organic electroluminescent devices with mixed single layer consist of distyrylbiphenyl derivative(DPVBi)and triphenylamine derivative (TPD) are studied. Blue electroluminescence was observed from this device, and white emission was observed from the devices with mixed single layer containing DPVBi, TPD and dicyanomethylene derivative (DCM). The maximum luminance was 2750cd/m^2 at 11V in ITO/DPVBi+TPD+DCM[66 : 34 : 0.1] (1000Å)/AcMg device. In the devices containing DPVBi, TPD, Nile Red and coumarin 540,pure white emission could be optimized by adjust mixing concentration of phenoxazone and coumarin 540.

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We fabricated the phosphor layer of TFEL devices using the electron beam evaporation method. The mixture of SrS : CeCl_3 and ZnS was used as a source pellet. The composition ratio of thin films was evaluated by RBS and PIXE. The structure and crystallinity of thin films were evaluated by SEM and XRD.

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Ce-doped Sr thiogallate (SrGa_2S_4 : Ce) films for blue-emitting thin-film electroluminescent devices have been prepared by multi-source deposition techniqe using Sr, Ga_2S_3 and CeF_3 source. It is found that when Ga_2S_3 evaporates from the source, it decomposes into GaS and S_2. Therefore, reactions between Sr, GaS, and S_2 should be considered in the deposition process. It was found that the formation of SrGa_2S_4,SrS, or GaS depends strongly on the substrate temperature and flux ratio of Ga_2S_3 to Sr. The SrGa_2S_4 : Ce film showing blue luminesence with peak 445 and 490 nm was deposited at a substrate temperature of 450℃, a flux ratio of Ga_2S_3/Sr=300 and at a annel condition of 600℃ for 3 hours.

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It is known that hot elrctrons that excite luminecsent centers are injected into an emitting layer from p-Si as a result of the band bending in Si at the interface between SiO_2 and p-Si. The preparation of the EL device/MOS FET structure has been tried in view of the interaction of the EL display on Si substrate by applying the above fact. About 10cd/m^2 was obtained from the device of ITO/ZnS : Tb/SiO_2/p-n Si/Al structure. However it has shown that the process of ITO patterning, the thickness of SiO_2 layer and the formation process of p-n junction must be discussed to obtain EL emission under the operation of FET and to improve the EL characteristics.

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Liquid crystal spatial light modulator (LC-SLM) is a optical to optical image converter. This device includes p-i-n photoconductor and reticulated aluminum light reflection mirror. In this paper, the resistivity of photoconductive layer is found to be 10^9 and 10^<13>Ωcm in case of light irradiation and non irradiation respectively. This device has 12 : 1 contrast ratio and high resolution.

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A light scattering mode spatial light modulator, consisting of a hydrogenated amorphous silicon thick-film (30μm) which is deposited by means of an ECR plasma CVD method, has been developed for a large screen projection display. The device has good characteristics, such as a high photosensitivity (1mw/cm^2), a high resolution (50lp/mm), and a high extinction ratio (100 : 1).

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For one of improvement methods of viewing angles for large size TFT-LCD, we developed a compensation method of brightness shading that observed remarkably from upper side of LCD screen to lower side of that. Using Capacitivity coupled driving method, we could compensate for brightness shading by changing vias voltage every gate driving lines corresponding to viewing angle.

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A design scheme of the optics of the OCB (Optical Compensated Birefringence) is shown. A low Δnd was chosen to avoid the greyscale inversion and blueish coloration at a deep offangle, which is caused by the rotation of the blue light. An optimizing the cell thichness for each RGB pixel reduced the coloration and simplified the greyscale settings. The normally white mode was chosen to reduce the dependencies on the cell thickness.

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Several experiments are introduced, which have been performed on plasma production and control for next-stage plasma processing in conjunction with dry etching, a-Si film formation, etc. Using a plane slotted antenna with permanent magnets, we can produce uniform ECR plasmas of almost 50 cm in diameter, which are unmagnetized in the region a little far from the ECR position. Electron temperature can be controlled by producing a local structure in plasmas. Two methods using a pin-hollow cathode and a coarse separation grid have been established for the electron-temperature control. The electron temperature can now be controlled in the wide range from a few eV to 0.3 03 0.03 eV.

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The conduction mechanism in poly-Si TFT is investigated in detail using a new device simulator based on Monte Carlo method. In this simulator, the influences of grain boundaries on the electrical conduction are represented by the grain boundary traps. The potential barriers are formed at the grain boundaries by the trapped electrons. The conduction electrons are repelled by these potential barriers and consequently the current flow decreases. It is found from the simulation results that these potential barriers are reduced more significantly near the poly-Si-gate oxide interface by applying the gate voltage and consequently the current flow is confined near the interface. It also turns out that holes generated by the impact ionisation significantly influence the channel electron conduction through reducing the barrier height at the grain boundary. This is the origin of the avalanche induced short channel effect in poly-Si TFT.

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The test system has been developed for measuring the Id-Vg characteristics and the capacitance of the complete TFT/LCD assembly. The driver IC is used as the multiplexer for sensing the charge from each pixels. The method for measuring the drain current, the capacitance of liquid crystal and other capacitance was developed. Both the drain current and the capacitance obtained with this system have been correlated to the value measured by the conventional equipment. The MOS capacitance between the gate and the source was measured and characterized.

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A low resistivity Mo-W alloy has been developed which is applicable to large area and high definition TFT-LCD gate lines with simple process. Mo-W alloy has low resistivity of 15μΩcm and has chemical and thermal stability. Therefore, Mo-W alloy is applicable to high definition displays such as XGA and workstation. In this development, sputtered Mo-W alloy film characteristics and taper etching process were evaluated and feasibility for large area and high difinition TFT-LCDs were confirmed by fabricating 9.5 inch diagonal VGA and 13.8 inch diagonal workstation.

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We have developed a self-aligned offset gate technology with anodic oxidation of Al for low temperature poly-Si TFT-LCD. This technology allows us to control the optimum offset length precisely for pixel TFTs and driver TFTs respectively. As a result we have achieved high performance TFTs ; low leakage current (1.0pA/μm for pixel TFTs), high field effect mobility (Nch 174 cm^2/V・s, Pch 66 cm^2/V・s for driver TFTs) and high reliability. Then we have fabricated 3.7 inch diagonal driver monolithic TFT-LCDs.

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LCD cells with either a monodomain LC medium having a controlled tilt angle or dual domain medium having also well controlled two tilt angles have been fabricated by the photo-curing of the small amount of photocurable doped monomers (≦3wt% of LC) under the simultaneous application of an electric field and a magnetic field, even though no surface pretilt exists. Using this technique, we have successfully fabricated a dual domain Tunable Birefringent mode LCD cell and a Twisted Nematic LCD cell. These LCD cells exhibit symmetric and wide viewing angle characteristics.

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Polymer dispersed liquid crystal (PDLC) cells are prepared using a UV curable liquid crystal as a polymer matrix. Reverse mode properties, that is, the PDLC cell is transparent in the off-state and becomes scattered-state in the on-state, can be obtained in homogeneous type PDLC cells and twisted nematic type PDLC cells using a nematic liquid crystal with a positive dielectric anisotropy and homeotropic type PDLC cells using a liquid crystal with a negative dielectric anisotropy. The response time of these cells are the same order as those of a conventional droplet type PDLC cell. The homeotropic type PDLC cell has a very short decay time, that is a few ms. The viewing angle property in the transparent state becomes wider than that of the conventional droplet type PDLC cell.

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This report is an electro-optic characteristics and the sunshine exposure test for PDLC device which in growing a phase separation structure as well as the cell membrane and a droplet diameter is 2-3μm.

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Electrooptic effects using a light scattering have been studied in a ferroelectric liquid crystalline polymer (FLCP)and a bistable switching has been demonstrated. The electroptic effects including a deformation of helical structure (DHS) upon applying voltage and a transient scattering mode (TSM) at the instant of polarity reversal of applied voltage have been observed in FLCP. During the TSM operation at the polarity reversal a stripe texture parallel to the smectic layer has been observed for an instant with a polarized microscope, which is explained in terms of the transient construction of the helical structure at the polarity reversal. The helical structure which is constructed at TSM operation has been maintained even after the removal of voltage. Using these effects, a new type of bistable switching between transparent and opaque states has been realized by means of the application of pulse voltage.

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