Patent · US Expired

Optical disc with different wobble patterns in different grooves

US7167438B2 · kind B2 · utility

1Cited by
4References
11Claims
0Family size

Assignees

Inventors

Key dates

Filing dateOct 16, 2002
Grant dateJan 23, 2007
Priority date
Expiry dateAug 7, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2220/2575
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The S/N ratio is improved for recording data to grooves (2-1,2-2) of an optical disc so that as much information as possible can be recorded at the lowest possible frequency band. An optical disc using wobble patterns to record different information has a first groove (2-1) having a first wobble pattern (22) in which one wobble period has a sharp rising edge and a gradual falling edge; and a second groove (2-2) having a second wobble pattern (24) in which one wobble period has a gradual rising edge and a sharp falling edge. Each of the first and the second wobble pattern is represented by a first fundamental and a second harmonic of a Fourier series. The polarity of the second harmonic, which is an even harmonic, of the second wobble pattern is opposite that of the first wobble pattern. A method for manufacturing this optical disc is also provided.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.