Contrast determining apparatus and methods
CA 2264861 C · Owner: Spectrum Technologies Plc · Inventors: Lau, Simon; Roberts, Brinley Rhys
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Apparatus for determining the contrast of a mark for, example lettering on a cable, uses a CCD sensor or the like to capture a two-dimensional image of the Mark. The pixel values from the CCD are thresholded into populations of black grey and, white. The average intensities of the "black" and "white" pixels are taken and an indicator of contrast obtained from the following formula: contrast = (I max - I min)/ I max where I max = average "white" pixels, I min = average "black" pixels.
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 September 4, 1997 and granted July 30, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 4, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 4, 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
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.