Optical head
CA 1302562 C · Owner: Imai, Hitoshi · Inventors: Koyanagi, Kimiyuki; Arai, Ryuichiro; Imai, Hitoshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical head for optical recording and reproducing system comprising a light source a first optical, means for introducing a light beam from the light source into a guide groove formed in a recording surface of an information carrier, and a second optical means for separating a reflected light beam reflected from the guide groove from the light beam from the light source. The optical head also comprises an optical element having formed thereon at its center a cylindrical surface and on both sides slanted surfaces for dividing the reflected light beam into three, and a light receiving element having at least three light receiving units for receiving the respective light beams divided into …
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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 June 2, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 2, 2009.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.