Symbol read device
CA 2043964 C · Owner: Nakazawa, Atsushi · Inventors: Nakazawa, Atsushi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A symbol read device useful as a bar code reader, optical character reader or the like. A symbol bearing surface is illuminated by two different light sources that are distinguishable based on their respective wavelengths or modulated frequencies. A detector detects light reflected from the symbol surface and provides a detection signal indicative thereof. The detection signal is processed to recognize the symbol being read. In a multi-scan embodiment, an automatic gain control (AGC) circuit controls a level of detector signal to aid in recognition of the symbols being read.
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
- Filed June 5, 1991 and granted April 23, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 5, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 5, 2013.
- 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.