Method and apparatus for decoding bar code symbols using ratio analysis of module size
CA 2267892 C · Owner: Lei, Ming · Inventors: Lei, Ming
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved method and apparatus for decoding bar code symbols using an analysis of the ratios of the module size for the bars and spaces of the bar code. The invention is applicable to any bar code having one or more nominal widths in the bars and spaces and is par-, ticularly useful in bar codes having multiples widths in the specification for the bar code and in situations where the bar code signal has a low signal-to-noise ratio, or is degraded because of a damaged smudged, or dirty bar code, or where the bar code is read at less than the optimum angle. The invention identifies misdecoded characters and uses adaptive techniques to decode characters previously non-decodable or misdecoded …
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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
- Filed October 1, 1997 and granted September 10, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 1, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 1, 2019.
- 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
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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.