The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Jun. 20, 1995

Filed:

Aug. 11, 1994
Applicant:
Inventors:

Shigenori Murakami, Yamanashi, JP;

Toshihiko Takishita, Yamanashi, JP;

Kenji Suzuki, Yamanashi, JP;

Kiyohide Ogasawara, Yamanashi, JP;

Hiroshi Ito, Yamanashi, JP;

Assignees:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
3692754 ; 369288 ; 4286 / ; 4286 / ;
Abstract

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.


Find Patent Forward Citations

Loading…