Global Patent Index - EP 1000424 A2

EP 1000424 A2 2000-05-17 - OPTICAL RECORDING MEDIUM

Title (en)

OPTICAL RECORDING MEDIUM

Title (de)

OPTISCHER AUFZEICHNUNGSTRÄGER

Title (fr)

SUPPORT D'ENREGISTREMENT OPTIQUE

Publication

EP 1000424 A2 (EN)

Application

EP 99921038 A

Priority

  • EP 99921038 A
  • EP 98201771 A
  • IB 9900958 W

Abstract (en)

[origin: WO9962061A2] An optical recording medium is described having a grooved recording layer. The structure of unwritten tracks must enable a scanning device to derive a radial tracking error signal according to the push-pull method. The structure of the written tracks must enable the scanning device to derive a radial tracking error signal according to the high-frequency phase-detection method. To this end the width and depth of the groove are in the range from 0.3 to 0.6 times the wavelength over the numerical aperture of the radiation beam used for scanning the recording medium, and from 1/24 to 1/7 times the wavelength over the refractive index, respectively. The phase difference between the radiation beam reflected from a region on track in between written marks and from a mark is in the range from 0.4 to 2.0 radians.

IPC 1-7 (main, further and additional classification)

G11B 7/0037; G11B 7/24

IPC 8 full level (invention and additional information)

G11B 7/0037 (2006.01); G11B 7/007 (2006.01); G11B 7/09 (2006.01); G11B 7/24079 (2013.01)

CPC (invention and additional information)

G11B 7/24079 (2013.01); G11B 7/007 (2013.01); G11B 7/0938 (2013.01); G11B 7/0901 (2013.01); G11B 7/0943 (2013.01)

Citation (search report)

See references of WO 9962061A3

Designated contracting state (EPC)

DE FR GB

EPO simple patent family

WO 9962061 A2 19991202; WO 9962061 A3 20000217; WO 9962061 A8 20000413; CN 1150537 C 20040519; CN 1272204 A 20001101; EP 1000424 A2 20000517; JP 2002517058 A 20020611

INPADOC legal status


2004-01-07 [18W] WITHDRAWN

- Effective date: 20031113

2000-05-17 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20000228

2000-05-17 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A2

- Designated State(s): DE FR GB