Patent Yard Sign in
Expired Canadian patentCanada

Optically transparent yttrium oxide

CA 1303825 C · Owner: Greenberg, Michael · Inventors: Hartnett, Tom; Greenberg, Michael; Gentilman, Richard L.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

A transparent yttrium oxide ceramic is made by densifying a yttrium oxide powder without addition of dopants. The yttrium oxide powder is consolidated into a body of a predetermined shape and sintered to a density such that any remaining porosity is sealed from the surrounding atmosphere. The closed porosity body is then subjected to an elevated pressure and temperature to provide the body with substantially 100% of theoretical density. The resulting body has substantial transparency over the wavelength range of .6 µm to 7 µm.

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

  • Granted June 23, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 23, 2009.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJanuary 25, 1988
GrantedJune 23, 1992
Term endedJune 23, 2009
Patent numberCA 1303825 C
Classification (IPC)C04B35/50 +2 more

Timeline

Timeline From CIPO dates

1989199219951998200120042007Application filedJan 25, 1988Patent grantedJune 23, 1992Term endedJune 23, 2009

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.