Patent Yard Sign in
Expired Canadian patentCanada

Optical recording system

CA 1249056 A · Owner: Alcatel Thomson Gigadisc · Inventors: Romeas, Rene

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

An optical recording disk comprises a track divided into sectors and having a longitudinal axis. Areas on this track for writing data using a predetermined increment alternate with prewritten marker areas. Each of these comprises at least two patterns having leading and trailing edges. Part of at least one of these patterns is offcenter relative to the track axis and associated with at least one edge of a pair of leading and trailing edges combined with another pair of leading and trailing edges to define along the axis two predetermined distances. Each of these distances is between two consecutive multiples of the data writing increment. The patterns are adapted to be scanned optically in …

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted January 17, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 17, 2006.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJuly 8, 1985
GrantedJanuary 17, 1989
Term endedJanuary 17, 2006
Patent numberCA 1249056 A
Classification (IPC)G11B7/00 +2 more

Timeline

Timeline From CIPO dates

1986198919921995199820012004Application filedJuly 8, 1985Patent grantedJan 17, 1989Term endedJan 17, 2006

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.