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Abstract— The dependency of the chromaticity shifts on the concentration of Eu2+ doped in BaMgAl10O17 (BAM) was investigated under heat‐treatment and vacuum ultraviolet (VUV) irradiation. The Eu2+ ions in BAM show an asymmetrical broad emission band with a maximum at ∼452 nm under excitation of VUV light at room temperature, showing that multiple crystalline cationic sites exist in the host. It was found that the chromaticity shifts greatly decrease with increasing heat‐treatment temperature. Regardless of the Eu2+ concentration, the chromaticity shifts caused by heat‐treatment are greater than that caused by VUV irradiation. Compared with conventional BAM, a solid solution of BAM with barium aluminate as a powder and film was also studied, and very few chromacity shifts were observed. It is suggested that the distribution of Eu2+ ions in different sites in a BAM lattice results in different chromaticity coordinates. By increasing the Eu2+ concentration in BAM, or under heat‐treatment and VUV irradiation, the emission band shifts towards longer wavelengths.

The luminescence properties of blue phosphors 0.9BaOÁ0.1EuOÁMgOÁmAl 2 O 3 with m ¼ 3:5 to 8.0 were investigated for color plasma display panel (PDP) applications. The deterioration properties of the phosphors baked in air and irradiated under vacuum ultraviolet (VUV) rays were systematically studied with different alumina contents m. The results indicate that the phosphor with m ¼ 5:0 shows a relatively more stable color chromaticity after the baking process and VUV irradiation, whereas the phosphors with m ¼ 5:5 to 8.0 show small decreases in the emission intensity compared to the phosphor with m ¼ 5:0 after VUV irradiation. These decreases in the emission efficiency are ascribed to the irregular order of the Eu 2þ ions in the intermediate layer and the shifts of the chromaticity coordinates to the changes of the Eu 2þ sites, which are suggested to occupy unstable Beevers-Ross and/or mid-oxygen sites in the host.

After decades of research and development, plasma displays are finally beginning to appear in the commercial and consumer markets. Following a short review on the basic principles of direct and alternating current plasma displays, we present a summary of the status of color plasma displays. Plasma display panels (PDPs) have finally achieved luminance and efficiency values on par with hi-definition cathode ray tube monitors. Additional improvements in performance will open up a new world of large PDP displays. Ultimately, what will drive the PDP market will be continued improvements in the performance of color PDPs themselves. PDP makers are working on reducing power consumption through improved luminous efficiency and improved component materials and manufacturing methods of color PDPs. With improvements in the cell structure and driving methods, there is a good prospect of achieving a luminous efficiency of 2-3 lm/W and a power consumption of about 200 W for 50-in diagonal size.

Abstract— Vacuum ultraviolet (VUV) rays emitted from Xe during the operation of surface‐discharge ac plasma‐display panels (PDPs) were observed directly by using a recently developed ultra‐high‐speed electronic camera. It is confirmed that 147‐ and 173‐nm VUV rays are emitted from both the cathode and the anode simultaneously. The direct observation shows that the emitting area for 147‐ and 173‐nm emissions above the cathode and the anode extends outward from the edge of the gap. These emission extensions are considered to be caused by a lowering of the electric field above the area due to the accumulation of wall charges. The intensity of the 147‐ and 173‐nm emissions above the anode decays faster than those above the cathode. It is clarified that the difference in the decay characteristics of VUV rays above the cathode and the anode is caused by the difference in the wall‐charge‐accumulation rates above the cathode and the anode. The major reactions concerning the generation of Xe(1s4), a xenon resonant state, which is related to 147‐nm emission, and that of Xe2Y*, a xenon molecule state, which is related to 173‐nm emission, are discussed.

Improvement in longevity of blue phosphor (Eu 2+ -activated barium magnesium aluminate, call as BAM) is investigated for the application of color plasma displays. It is clarified that the properties of phosphor deterioration caused by the irradiation of vacuum ultraviolet rays are dependent on the substituted elements for the specific part of the BAM. The longevity of the modified BAM is longer than that of the conventional one by twice or more by means of the substitution of In, Lu or Sc.