Panasonic Assigned Patent

Panasonic Corporation, Osaka, Japan, has been assigned a patent (8,619,527) for “optical disk device, optical disk control method, and integrated circuit.“

The inventors are Tsuyoshi Nakasendo, Masaru Yamaoka, Yuji Takagi and Makoto Usui (Osaka, Japan).

The abstract of the patent published by the U.S. Patent and Trademark Office states: “To provide an optical disk device, an optical disk control method and an integrated circuit, which are capable of writing a recordable mark by changing the reflectance ratio of a reflective film formed on concave-convex pits without using an industrial special device or a high-power laser light source. A data reproduction controller (103) sets a first rotation speed in a disk rotation speed switching unit (108) and a first laser power in a laser power switching unit (107) when reproducing the concave-convex pits. When writing the recordable mark, a mark recording controller (104) sets in the disk rotation speed switching unit (108) a second rotation speed that is slower than the first rotation speed and the lowest rotation speed at which the concave-convex pits can be reproduced, and sets a second laser power greater than the first laser power in the laser power switching unit (107) in accordance with the emission timing.”

The patent was filed on Dec. 17, 2010.