Pioneer Corporation

Other

Makoto Matsukawa

Toshihiko Takishita

Seiro Oshima

Masahiro Kato

Eiji Muramatsu

Shoji Taniguchi

Takashi Chuman

Ayako Yoshida

Tatsuhiro Yone

Takeru Okada

Atsushi Yamaguchi

Takao Tagiri

Chihiro Harada

Akira Hirasawa

Shigenori Murakami

Shinichi Hanzawa

Ayumi Mitsumori

Miki Kusama

Kazuhiro Yamato

Atsushi Kondo

A light-emitting device () includes a first light-emitting member () and a second light-emitting member (). Each of the first light-emitting member () and the second light-emitting member () includes a first surface () and a second surface (), and light is emitted from the first surface (). The first light-emitting member () includes a first region () and a second region (), the first region () of the first light-emitting member () being located on the second surface () side of the second light-emitting member () and the second region () of the first light-emitting member () being located on the first surface () side of the second light-emitting member ().

Light-emitting device

An optical recording medium is provided which comprises: a substrate including concentrically or spirally formed grooves each having a V-shaped cross section; a first dielectric layer formed on the substrate; a phase-change recording layer formed on the first dielectric layer; a second dielectric layer formed on the phase-change recording layer; and a metallic reflecting layer formed on the second dielectric layer. In particular, the optical recording medium is so formed that an objective lens having an aperture number of 0.55-0.70 can be used and a laser beam having a wavelength of 600-700 nm and passing through the objective lens is passed through the substrate and then converged on the recording layer, thereby recording or reproducing information on the recording layer in areas corresponding to the grooves. Specifically, the optical recording medium further comprises a third dielectric layer consisting of a nitride, the third dielectric layer being disposed between the first dielectric layer and the phase-change recording layer. In this way, it is possible to prevent a deterioration possibly caused due to a heat in the boundary between the first dielectric layer and the second dielectric layer, thereby greatly increasing the number of possible times for over-write recording.

Optical recording medium

A recording medium includes pairs of groove tracks and land tracks having periodically formed bent portion provided side by side on a substrate, a plurality of land prepits previously formed on the land tracks and carrying information about the groove tracks, and a recording layer formed on at least the groove tracks and the land tracks. The land prepits have a radius of mean curvature smaller than a radius of mean curvature of sides of the groove tracks in land-prepit absent regions of the land prepits and are defined by curved surfaces continuously extending from the sides of the groove tracks. Those sides of the groove tracks which face the continuous curved surfaces of the land prepits are curved surfaces that stricture the groove tracks. The depth of the land prepit is larger than that of the groove track.

Recording medium and apparatus and method for manufacturing the same

An optical recording medium has a substrate having an annular grooves, a recording layer including an organic coloring matter and formed on the substrate, and a metallic reflection layer. The recording layer has a thickness so as to have an absorbance between 0.65 and 0.75. Information is recorded in the recording layer by a laser beam having a wavelength between 600 and 700 nm, using an objective lens having a numerical aperture between 0.55 and 0.70.

Two-disc laminated optical recording medium

Growing community of inventors

Yamanashi-ken, Japan

Makoto Matsukawa