Wavelength switching light source
CA 2102270 C · Owner: Nec Corporation · Inventors: Shiozawa, Takahiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The output light of a variable-wavelength light source 101 is brought to incidence on an optical resonator 103 having a periodic transmitting characteristic and the, transmitted light is detected by an optical intensity detector 105 and, having the difference from a reference level as the error signal, fed back by an operational amplifier 106 to the variable-wavelength light source 101. Therefore the output light frequency of the variable-wavelength light source 101 is stabilized at the shoulder of the peak of the transmitting characteristic (the point where the transmittance varies) of the optical resonator 103. Wavelength switching is accomplished by selecting one out of two variable …
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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 November 2, 1993 and granted April 6, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 2, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 2, 2015.
- 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.