Ultralow-loss silica glass and optical fibers using the same
CA 2260988 C · Owner: Toyota Jidosha Kabushiki Kaisha · Inventors: Saitoh, Kazuya; Ikushima, Akira
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This ultralow-loss glass is characterized in that high purity silica glass contains 1 to 500 wt.ppm of at least one network modifying oxide. It is assumed that the network modifying oxide appropriately loosens the tetrahedral network structure of silica and hence Rayleigh scattering is decreased. Examples of the network modifying oxide include Na 2 O, K 2 O, Li 2 O MgO, CaO, and PbO. Since, Rayleigh scattering losses are minimal in comparison with these of high purity silica glass, this impurity-added silica glass is excellent as a base material of a glass fiber for a long-distance transmission.
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 July 14, 1997 and granted October 29, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 14, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 14, 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.