Low distortion hydrophone
CA 2176162 C · Owner: Syntron, Inc. · Inventors: Erath, Louis W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system and method provide a low distortion hydrophone. A first known piezoelectric element is mounted so as to receive a pressure signal. A second piezoelectric element is provided with a means of receiving and enhancing the same pressure signal. Since a piezoelectric element is a capacitor another capacitor is coupled, in parallel with the second element to serve as a divider. The output voltage of the combination of the two elements is taken as the difference between the positive terminals of the two elements. Thus the effect of the pressure enhancer and capacitance divider is to provide a difference in potential between the fundamentals from the two elements, while rendering the …
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 May 9, 1996 and granted October 27, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 9, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 9, 2018.
- 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.