Pioneer Electronic Corporation

Pioneer Video Corporation

Other

Shigenori Murakami

Toshihiko Takishita

Eiji Muramatsu

Shoji Taniguchi

Akiyoshi Inoue

Hiroyuki Takahashi

Kenji Suzuki

Kiyohide Ogasawara

Hiroshi Ito

Makoto Matsukawa

Shinichi Hanzawa

Atsushi Kondo

Ayumi Mitsumori

Miki Kusama

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

A recordable optical disc on which information is recorded by applying a light beam on the surface thereof, includes: a first recording area on which information is recorded and reproduced while the disc is rotated at a first linear velocity; and a second recording area on which information is recorded and reproduced while the disc is rotated at a second linear velocity. The first recording area and the second recording area include guide grooves having wobble frequency lower than frequency band of EFM signal.

Optical disk having first and second recording areas with wobble

An apparatus for recording information on a recordable optical disc by applying a light beam on the surface thereof, the disc includes a first recording area on which information is recorded and reproduced while the disc is rotated at a first linear velocity; and a second recording area on which information is recorded and reproduced while the disc is rotated at a second linear velocity. The first recording area includes a test recording area. The apparatus includes recording power determining unit for determining first optimum recording power for recording information on the first area by a test recording utilizing the test recording area, and for determining second optimum recording power for recording information on the second area by multiplying the first optimum recording power by a predetermined constant.

Apparatus for and method for determining optimum power for recording

An optical information recording medium recordable of the analogue NTSC color video signal under the conditions of a high S/N ratio and a low jitter, and capable of being played by a commercially available LD player. The medium comprises: a transparent substrate on which pre-grooves are formed with a depth of 1450-2050 angstroms; an optical absorbing layer with an absorbance of 0.7-0.9 made of palladium phthalocyanine dye formed on the substrate, the absorbing layer having pits each having a changed reflectivity being duty-cycle modulated in response to a limited waveform which is formed through the steps of: adding at least one of a second FM carrier and a third pulse carrier to a first FM carrier having a first center frequency and a first frequency band, the second FM carrier having a second center frequency lower than the first center frequency and a second frequency band spaced from the first frequency band, the third pulse carrier having a pulse-repetition frequency lower than the second center frequency and a third frequency band spaced from the second frequency band, to form a frequency-division multiplex signal; and symmetrically clipping the multiplex signal to form the limited waveform; and reflecting layer formed on the optical absorbing layer.

Information recording medium and method for recording information to the

Growing community of inventors

Koufu, Japan

Shigenori Murakami