Athermal tunable filters with wavelength and intensity responses based on volume phase hologram
CA 2424798 A1 · Owner: Sanshin Optique Inc. · Inventors: Yin, Shizhuo; Luo, Fang; Sheng, Yunlong
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to an athermal tunable filter in which the wavelength and intensity responses of the filter can be independently tuned by moving the location of the filter. The filter is fabricated by recording multiple, volume phase holographic gratings in highly stable photosensitive glasses (e.g. Ge-doped fused silica optic fiber preforms). The athermal operation is realized, by an innovative design, in which the shift of the effective grating period induced, by the thermal-optic effect is automatically compensated by the shift of incident, and output beam angles. In addition by recording the gratings in selected, areas the intensity response of the filter can also be …
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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 April 9, 2003. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 9, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 9, 2025.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.