Pioneer Corporation

Mitsubishi Kagaku Media Co., Ltd.

Hiroshi Nishiwaki

Junichi Furukawa

Yoshio Sasaki

Shoji Fuse

Eiji Muramatsu

Takayuki Nomoto

Takanori Maeda

Michikazu Horie

Ikuya Kikuchi

Mitsuru Sato

Toshihiko Takishita

Kazuo Takahashi

Seiro Oshima

Kenjirou Kiyono

An information recording medium () is provided with (i) a first information recording area wherein a first track for reproducing first information based on a first track pitch is formed by a laser beam, and (ii) a second information recording area wherein a second track for reproducing second information based on a second track pitch different from the first track pitch is formed by a laser beam. The groove shape of the first track is different from the groove shape of the second track.

Information recording medium, information reproducing device and method, and apparatus and method for manufacturing information recording medium

An information recording apparatus () is provided with: a recording device () for recording information onto an information recording medium () by irradiating the information recording medium with a recording laser beam (L); a controlling device () for recording calibration data onto the information recording medium by using the recording laser beam in which the power is adjusted gradually; and a detecting device () for detecting with a push-pull signal after the recording of the calibration data, the recording of the calibration data being ended if the push-pull signal exceeds a predetermined range, an optimum power of the recording laser beam being determined from a jitter amount included in a reproduction signal.

Information recording device, method, and computer program

An information recording apparatus () is provided with: a recording device () for recording information onto an information recording medium () by irradiating the information recording medium with a recording laser beam (L); a controlling device () for recording calibration data onto the information recording medium by using the recording laser beam in which the power is adjusted gradually; and a detecting device () for detecting degree of modulation of a reproduction signal after the recording of the calibration data, the recording of the calibration data being ended if the degree of modulation exceeds a predetermined range, an optimum power of the recording laser beam being determined from a jitter amount included in a reproduction signal.

Optical disc recording apparatus and method, and computer program

An information recording apparatus () is provided with: a recording device () for recording information onto an information recording medium () by irradiating the information recording medium with a recording laser beam (L); a controlling device () for recording calibration data onto the information recording medium by using the recording laser beam in which the power is adjusted gradually, thereby obtaining the optimum amount of the recording laser beam; and a detecting device () for detecting returned light simultaneously with the recording in the recording of the calibration data, the recording of the calibration data being ended if amount of the returned light exceeds a predetermined range, an optimum power of the recording laser beam being determined from a jitter amount included in a reproduction signal.

Optical disc recording device, method, and computer program

A recording layer close to a disc surface is divided into at least two recording areas, a main information recording area DA and an auxiliary information area (BCA) DC. Grooves are formed in the main information recording area DA. Marks M are formed in barcode form representing identifying information in the auxiliary information recording area (BCA) DC. Track grooves Gor prepits are formed in the recording layer of the auxiliary information recording area (BCA) DC and have a depth smaller than that of the groove formed in the main information recording area DA.

Optical disc

A detection signal Soutputted from a light reception unit (A) of detection elements () formed by four-division light reception element is added to a detection signal Soutputted from a light reception unit (D) so as to obtain an addition signal Sand a phase difference signal Pindicating the phase difference between the addition signal Sand the detection signal SFurthermore, a phase difference signal Pindicating the phase difference between the addition signal Sand the detection signal Sis obtained. The phase difference signal Pis subtracted from the phase difference signal Pso as to generate a tracking error signal TE

Tracking error signal generation device and tracking error signal generation method

A tracking servo apparatus in which reflection light obtained when a laser beam is irradiated onto a recording surface of an optical disc is photoelectrically converted, thereby obtaining a photoelectric conversion signal, a tracking error signal showing a deviation amount of an irradiating position of said laser beam for a track in a disc radial direction on the recording surface is generated by the photoelectric conversion signal, a spherical aberration occurring in an optical system is detected, a level of the tracking error signal is corrected on the basis of the detection result, and the irradiating position of the laser beam is moved in the disc radial direction in accordance with the level-corrected tracking error signal.

Growing community of inventors

Kawasaki, Japan

Hiroshi Nishiwaki