Patent Yard Sign in
Expired Canadian patentCanada

Compound modulation transfer function for laser surgery and other optical applications

CA 2575202 C · Owner: Dai, Guangming · Inventors: Dai, Guangming; Yee, Kingman

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

Methods, devices, and systems establish an optical surface shape that mitigates or treats a vision condition in a patient. An optical surface shape for a particular patient can be determined using a set of patient parameters for the specific patient by using a compound modulation transfer function (CMTF). The compound modulation transfer function can include a combination of modulation transfer functions (MTF's) at a plurality of distinct frequencies.

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 27, 2005 and granted September 3, 2013. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 27, 2025.
  • Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJuly 27, 2005
GrantedSeptember 3, 2013
Term endedJuly 27, 2025
Patent numberCA 2575202 C
Classification (IPC)A61B3/00 +1 more

Timeline

Timeline From CIPO dates

2006200820102012201420162018202020222024Application filedJuly 27, 2005Patent grantedSep 3, 2013Term endedJuly 27, 2025

Sources & verification

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