The properties of the luminous colors of the discharge tubes which are filled with a mercury-xenon mixture and which are coated with the fluorescent lamp phosphors and the plasma-display-panel phosphor's, have been studied experimentally. The former phosphors are intensely radiated in a high-frequency discharge. On the other hand, the latter phosphors are radiated in a pulsed discharge more strongly than the formers. However, because the excitation levels of mercury and xenon have nearly same energies, the luminous color of a fluorescent lamp may not be changed widely.

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A flat fluorescent lamp is getting popular as a backlight for a color LCD in an electric view finder(EVF) because of its suitable shape and compact size. Ar/Hg system is mainly applied to this lamp. However, there are some weak points of the system; for example, low luminance and luminous color changing at low ambient temperatures because of decrease of mercury vapor pressure. Ar/Xe/Hg system eventually has given a solution to the above mentioned problems. A rare-gas flat fluorescent lamp by adapting the system has been developed. Some new characteristics of the rare-gas flat fluorescent lamp are intoroduced.

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A new antireflective and antistatic coating with ultra-fine particles is developed . The coating consist of two layers; an antireflective layer of SiO_2 ultra-fine particles that is consistently a single particle thick, and a conductive layer composed of multiple SnO_2 ultra-fine particles. The outer surface of the antireflective layer is alternately concave convex, owing to the arrangement of SiO_2 particles, and the refractive index of this layer therfore decreases gradually from its inner to outer surface. Thus, the total reflectivity can be reduced. The coating provides low reflectivity and electrical resistance in addition to high resolution and contrast.

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A pigmented phosphor panel is commonly used to improve contrast. Application of a pigmented phosphor is unlikely to significantly improve contrast because of lowering brightness. Another method employed to improve contrast is using a low transmittancepanel. The panel may lower brightness because of its low transmittance, but the decrease in ambient light reflectance is in proportion to the square of the transmittance of the panel, so contrast is very much improved. A high brightness. high contrast and high color purity CRT has been realized by the application of a color filter of inorganic ultra-fine pigment placed between the phosphors and the panel glass.

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A stray emission current distribution in the beam forming region of a CRT gun was investigated by means of the anode-hole scanning method. The equipment used in the study has a moveable anode with a Farady cage. G1 and a dispenser cathode. The distirbution of grid emission from a G1 aperture was measured with this equipment. The grid emission became observable during cathode aging process and was decreased with silicon oxide film deposited in the area of G1 aperture.

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We have developed an AC Powder EL Lamp with high luminance, high. emission efficiency and excellent thermal characteristics using barrier anodic aluminum oxide film as an insulator instead of the usual layer of dispersed BaTiO_3 in a binder. To determine the cause of the high efficiency, we measured the luminance and emission efficiency of the emission layer which connects with various RC parallel circuits in which R and C were varied. These RC parallel circuits are the equivalent of circuits of insulator layers. It was found that an ideal insulator layer of AC Powder EL Lamp has to have a combination of large capacitance and low tanσ. Barrier anodic aluminum oxide film has such characteristics. In addition anodic aluminum oxide film has such a stable temperature characteristics in regards to tanσ that thermal characteristics of emission efficiency was improved.

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The relationship of the structure and photoluminescent properties with the preparation condition of ZnF_2:Mn thin films deposited by electron beam evaporation has been investigated. It was found that when the pressure is in the order of 10^<-6> Torr, a fraction of the film gets oxidized forming ZnO if the substrate temperature is higher than 400℃. This oxidation process could not be observed even at 500℃ if the pressure lies in the order of 10^<-8> Torr. The crystallinity of the film was improved with increasing the substrate temperature and decreasing the pressure. Fluoride thin-film EL devices consisted of ZnF_2:Mn as an emission layer and CaF_2 as an insulating layer were also prepared and their EL properties were measured. EL intensity is observed to increase with the increase of substrate temperature. However, breakdown voltage of the EL device is decreased at higher substrate temperature. The mutual diffusion might he taken place in between CaF_2 and ITO causing breakdown of the device and this could be suppressed by inserting SiO_2 between the those two layers.

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To improve guality of SrS:Ce thin films and to improve EL characteristics ,the SrS:Ce thin films were prepared by using electron-beam evaporation under the controlled sulfur vapor pressure. The maximum luminance(Lmax) of 500〜600cd/m2 was obtained for the EL devices prepared at substrate temperature of 500-570℃ under sulfur vapor pressure of 2-4 × 10-4Torr, although the crystallinity of the films deposited at 550℃ was the best. By annealing of the SrS:Ce thin films in Ar-S atmosphere at 630℃ ,Lmax was increased and reached to 1000cd/m2. X-ray diffraction intensity and photoluminescent intensity were also increased by annealing. Surface morphology and cross-sectional view of the annealed films observed by Scanning Electron Microscope were also different compared with those of as-deposited films.

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We have measured the electrical characteristics of ZnS:Mn and the SrS:Ce thin-film EL devices, such as Q-V and Q-Fp curves. These are analyzed by using the bipolar trapezoidal voltage pulses. turn-on voltage of SrS:Ce thin-film EL devices is increased by increasing dv/dt, while turn-on voltage of ZnS:Mn thin-film EL devices hardly depends on the value of dv/dt. For both EL devices, luminance-transferred charge characteristics hardly depend on the value of dv/dt. These results suggest that generation of space charge in the SrS:Ce thin-films plays an important role in the excitation mechanism of the SrS:Ce thin-film EL devices.

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In order to achieve the bright blue electroluminescence, several electroluminescent devices doped with Tm^<3+> ion were investigated. It is considered that improvement in the luminance of ZnS:Tm^<3+> electroluminescent device is hardly. La_2O_2S host is expect~d to the promising material, and the condition in the deposition was studied. The La_2O_2S:Tm^<3+> thin film was obtained, however the luminance for La_2O_2S:Tm^<3+> EL device was very poor.

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ZnS:TbF_3 thin films were observed using TEM and X-ray diffraction. Strcture of TbF_3 was investigated. Accordingly the following results are obtained, (1) Tb atoms or particles disturb the formation of recrystalization of ZnS film. (2) The structure of TbF_3 belongs to YF_3 type orthorhombic system.(3)Grainsize grow larger by annealing.

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We have fabricated organic EL devices using perylene and poly(N-vinyl carbazole) (PVCz) as an emitting layer, configured as ITO/emitting layer/MgAg. The emitting layer was a mixture of perylene and PVCz in chloroform-based solution,and was spin -coated on the top of an ITO coated glass substrate. As the dopant concentration increased,the light emission varied from blue (peak wavelength 450 nm)to yellow green (535 nm) ,and the maximum luminance was achieved at 385 cd/m^2 for blue emission and 480 cd/m^2 for yellow green emission. The conventional EL devices (ITO/hole transport layer/ perylene/MgAg) showed yellow emission.

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In the present paper, we fabricated the field emitter arrays using two kinds of etching solution, the one was the etching by the acid and the other was that by the alkali. The rising voltage of the current from the field emitters etched by the alkali was lower than that etched by the acid. I-V characteristics showed reducible tendency during several measurements. The short-term fluctuation of emission current showed a tendency to increase gradually and to be stable after a few minutes.

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