Patent Number: 7,042,830

Title: Phase-change optical information recording medium, and optical information recording and reproducing apparatus and method for the same

Abstract: The present invention relates to a phase-change optical information recording medium comprising a recording layer which reversibly phase-changes between the crystalline phase and the amorphous phase by irradiation of a light having a recording wavelength of 390 to 430 nm, and a light transmittance thermally controllable layer showing a light transmittance varying according to temperature, in which the light transmittance increases at a rate of 0.2 to 0.7% / C.

Inventors: Shinotsuka; Michiaki (Kanagawa, JP), Iwasa; Hiroyuki (Kanagawa, JP), Yamada; Takao (Tokushima, JP), Matsushita; Toshio (Tokushima, JP), Kanbara; Yasuo (Tokushima, JP), Okauchi; Shigeki (Tokushima, JP)

Assignee: Ricoh Company, Ltd.

International Classification: G11B 7/24 (20060101)

Expiration Date: 5/09/02018