Hitachi, Ltd.

Hitachi Displays, Ltd.

Other

Panasonic Liquid Crystal Display Co., Ltd.

Shin Imamura

Masaaki Komatsu

Masatoshi Shiiki

Choichiro Okazaki

Hiromichi Yamada

Teruki Suzuki

Hidetsugu Matsukiyo

Tsutomu Yamada

Masakazu Sagawa

Toshiaki Kusunoki

Takashi Hase

Hirotaka Sakuma

Hitoshi Oaku

Kenji Okishiro

Yoshihiro Koseki

Masatoshi Shiiiki

To obtain effective luminance and light efficiency while avoiding discharge, it is necessary to sufficiently increase a current luminous efficiency of gas and an electron emission efficiency of an electron source. In a fluorescent lamp, an anode electric field is increased by setting a pressure of a noble gas or a molecular gas enclosed to 10 kPa or higher, setting an anode voltage to 240 V or lower, and setting a substrate distance to 0.4 mm or smaller. Furthermore, the resulting effect that the current luminous efficiency is increased in proportion to the electric field is used. Also, by applying a MIM electron source having an electron emission efficiency exceeding 10% as an electron source, a non-discharge fluorescent lamp having a light emission luminance equal to or larger than 10[cd/m] and a light emission efficiency equal to or larger than 120 [lm/W] is achieved.

Fluorescent lamp and image display apparatus

An object of the present invention is to provide a moving picture displayable liquid crystal display device capable of attaining satisfactory moving picture characteristics, color reproducibility and reliability at the same time. A liquid crystal display device according to the present invention comprises a white light source having a blue phosphor, a green phosphor, and a red phosphor and having a light-on state and a light-off state in a single frame; and a liquid crystal display panel which controls an amount of transmitted light from the white light source for each pixel, and which has a color filter for allowing one of blue light, green light, and red light to be transmitted therethrough for each pixel, in which at least one type of the blue color phosphor, green color phosphor, and red color phosphor is a phosphor mixture composed of at least two phosphors having different host material composition, and phosphors having a luminescence center of the same element are used for the phosphor mixture of the same color.

Liquid crystal display device with the mixture of the plural kinds of green phosphors

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

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 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

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.

Growing community of inventors

Kokubunji, Japan

Shin Imamura