Tokyo Shibaura Denki Kabushiki Kaisha

Kabushiki Kaisha Toshiba

Satoshi Sugano

Masao Asada

Yoshio Kimura

Kenji Terashima

Tsuyoshi Oyaizu

Hirofumi Takemura

Akira Mikami

Yohe Shimizu

Hiroyasu Yashima

A red emitting phosphor comprises a yttrium oxysulfide phosphor as a base material. A red emitting phosphor of medium particle size type has such a particle size distribution that a content of a component of a particle diameter of less than 4.0 &mgr;m is 15% or less, that of a component of a particle diameter of 4.0 &mgr;m or more and less than 8.0 &mgr;m is 75% or more, and that of a component of a particle diameter of 8.0 &mgr;m or more is 10% or less. A red emitting phosphor of larger particle size type has such a particle size distribution that the content of a component of a particle diameter of less than 5.04 &mgr;m is 20% or less, that of a component of a particle diameter of 5.04 &mgr;m or more and less than 10.079 &mgr;m is 70% or more, and that of a component of a particle diameter of 10.079 &mgr;m or more is 10% or less. Phosphor layers employing these red emitting phosphors are excellent in denseness. Accordingly, a cathode ray tube of high contrast and high quality can be provided.

Red emitting phosphor for cathode ray tube

Green-emitting phosphor

Fluorescent lamp

Growing community of inventors

Yokohama, Japan

Satoshi Sugano