Hitachi, Ltd.

Hitachi Displays, Ltd.

Other

Masaaki Komatsu

Masatoshi Shiiki

Shin Imamura

Choichiro Okazaki

Hiromichi Yamada

Teruki Suzuki

Hidetsugu Matsukiyo

Ryo Inoue

Tsutomu Yamada

Takashi Hase

Hirotaka Sakuma

Hitoshi Oaku

Kenji Okishiro

Yoshinori Aono

Yoshihiro Koseki

Masatoshi Shiiiki

There is provided a plasma display panel device using phosphors to improve reliability and color reproductivity or color performance. A plasma display panel includes: a discharge gas for generating ultraviolet light as a result of electric discharge, and a phosphor layer containing a phosphor for emitting light as a result of excitation by the ultraviolet light, in which the phosphor contains an Eu activated silicate phosphor added with at least one element selected from Al, Ga, Y and Gd, represented by the following General Formula (1):M1M2SiO:Eu&#x2003;&#x2003;(1)

Plasma display device

A liquid crystal display including a blink backlight system light source and a liquid crystal panel for adjusting the amount of light transmitted from the light source. The light source is made of a plurality of light emitting tubes each having one or more kinds of phosphors, and having a turned-on state and a turned-off state within one frame. A luminance factor area of light from each of the phosphors is substantially equal to that of light from any other phosphor in at least one of a luminance rise time when the light source changes from the turned-off state to the turned-on state and a luminance fall time when the light source changes from the turned-on state to the turned-off state.

Liquid crystal display

To provide an imaging device that shows high resolution and high luminance and produces good-quality images, an imaging device includes phosphor layer having a thickness of 40 &#x3bc;m or less and containing a phosphor having a composition represented by chemical formula: YTbScSiO, wherein 'x' and 'y' are atomic ratios and satisfy the following conditions: 0&#x3c;x&#x2266;1 and 0&#x3c;y&#x2266;1. The phosphor preferably has a strongest diffraction peak at diffraction angle 2&#x3b8; of 30.65&#xb0; to 30.9&#xb0; in X-ray diffraction for better properties. The phosphor can be prepared by firing a mixture of a compound containing Y, Sc, and Tb with a compound containing Si.

Imaging device with specific phosphor

The disclosed method can improve the luminescence life of an image display device. By using a blue luminescent phosphor having the phosphor component ZnS:M, N (where M is one or more elements selected from Cu, Ag, and Au, and N is one or more elements selected from Al, Ga, In, and Cl); wherein a shoulder is observed at around 400 nm (3.10 eV) of a cathode-luminescence spectrum of a field-emission display. A phosphor of a field-emission display of the present invention has improved characteristics against deterioration by electron-beam irradiation and an excellent luminescence maintenance factor, therefore, the luminescence life characteristics of a display are improved.

Image display device having a long-life phosphor layer

The luminance of phosphor is enhanced by forming a phosphor screen of a fluorescence generation unit by phosphor expressed by the following composition formula: (LGdCe)(AlGa)O:Mwherein, a, b and c are each in the following ranges of 0&#x2266;a&#x2266;1.0, 0&#x3c;b&#x2266;0.1 and 0&#x2266;c&#x2266;1.0, M is dopant of a monovalent metal element and is included in phosphor by approximately 0&#x3c;d&#x2266;1000 wt-ppm. Dopant M of a monovalent metal element is at least one type of element selected from a group consisting of K, Na, Li, Cu, Ag and Au. Thus, a display using a white light of improved luminescence and having excellent characteristics can be realized.

Light source and display using the same

The present invention relates to a field-emission display having a faceplate formed with a phosphor layer and means irradiating an electron beam onto the phosphor layer in order to improve the characteristic of life of the device. The feature of the present invention is in the structure of a phosphor layer. The phosphor layer is expressed by a general formula: ZnS: M, Al where M is an activator of at least one of Cu, Ag and Au; and Al is a coactivator, in which the concentration of Al is higher than that of M. According to the present invention, the electrification characteristic of the phosphor is improved for lower resistance. The defect concentration of the surface of the phosphor is reduced. The filed-emission display which can realize improvement in the characteristic of life which has not been solved in the prior art can be made.

Faceplate having specific phosphor

An image-display device using phosphor can improve the its luminescence efficiency and characteristics of color coordinates by adding an IIA element to a host crystal of ZnS phosphor to form a composite crystal. The image-display device improves the luminescence efficiency and color coordinate characteristics by using a phosphor expressed by Zn(1&minus;x)MIIAxS:MIB, MIII where MIIA is one or more IIA elements in periodic table of elements, MIB is one or more IB elements and MIII is one or more MIIIA elements such as Sc or Y.

Image-display device

A field-emission display apparatus includes a faceplate on which a phosphor layer is formed, and a means for irradiating electron beam onto the phosphor layer and the phosphor layer is constituted by phosphors formed by mixing main phosphors with small particle phosphors, the averaged particle diameter of which is smaller than &frac12; of an averaged particle diameter of the main phosphors, enhancing the filing density of the phosphor layer and also enhancing both a lifetime characteristic and a luminescent characteristic of the phosphor layer.

Display

A white light source includes an ultraviolet-visible excitation light generation unit capable of generating visible light and ultraviolet light, and a fluorescence generation unit having a phosphor layer and being capable of generating visible light upon excitation by the ultraviolet light and uses, in the phosphor layer, a red light emitting phosphor represented by the following compositional formula: (Ca Sr Eu )S:M , wherein a, b and c satisfy the following conditions: 0&lE;a<1.0, 0&lE;b<0.1 and 0&lE;c&lE;0.1; and M is a dopant element having absorption of excitation energy at about 350 nm to about 500 nm. The dopant element M includes rare earth elements such as Ce, Yb, Gd and Tm. By substituting part of Ca and/or Sr with Zn, the white light source can exhibit further improved performances. The white light source exhibits an increased red light component as compared with light emitted from conventional (Y Gd Ce ) (Al Ga ) O green light phosphors and is suitably used in display apparatus.

White light source and display apparatus using the same

Phosphor and imaging device using the same

Green-emitting phosphor having a composition formula represented by (Y Gd M ) Tb (Al Ga ) O , where 0<x&lE;1, 0&lE;a<1, 0<x&plus;a&lE;1, 0<y<1 and 0&lE;z&lE;1 and M is at least one of Sc, Yb and La, improves emission color of phosphors of Y (Al, Ga) O :Tb series, and in case that y&equals;0.07, z&equals;0.4 and a&equals;0 in the foregoing composition, color y is increased with increasing Gd concentration, when Gd concentration x is changed, and the emission color becomes clear green.

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Kodaira, Japan

Masaaki Komatsu