Method for making infrared polarizing glasses
CA 2005644 C · Owner: Noll, Frederick Ernest · Inventors: Jones, Kelly Evan; Noll, Frederick Ernest
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention is directed to the preparation of glass articles exhibiting a relatively broad band of high contrast polarizing properties in the infrared region of the radiation spectrum from glasses containing silver halide particles selected from the group consisting of AgCl AgBr, and AgI. The inventive method comprises the following five general steps:, (a) melting a batch for a glass containing silver and at least one halide selected from the group consisting of chloride, bromide, and iodide;, (b) cooling and shaping said melt into a glass article of a desired configuration;, (c) subjecting said glass article to a temperature at least above the strain point, but not in excess of 75°C …
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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 December 15, 1989 and granted June 10, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 15, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 15, 2011.
- 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.