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Expired Canadian patentCanada

Calculating zernike coefficients from fourier coefficients

CA 2620895 C · Owner: Visx Incorporated · Inventors: Dai, Guangming

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Abstract From the Canadian patent

Systems, methods, and devices for determining an optical surface model for an optical tissue system of an eye are provided. Techniques include inputting a Fourier transform of optical data from the optical tissue system inputting a , conjugate Fourier transform of a basis function surface determining a Fourier , domain sum of the Fourier transform and the conjugate Fourier transform calculating an estimated basis function coefficient based on the Fourier domain sum, and determining the optical surface model based on the estimated basis function coefficient. The approach is well suited for employing Fourier transform in wavefront reconstruction using Zernike representation.

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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 August 28, 2006 and granted April 22, 2014. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 28, 2026.
  • 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.
FiledAugust 28, 2006
GrantedApril 22, 2014
Term endedAugust 28, 2026
Patent numberCA 2620895 C
Classification (IPC)A61B3/00

Timeline

Timeline From CIPO dates

2007200920112013201520172019202120232025Application filedAug 28, 2006Patent grantedApril 22, 2014Term endedAug 28, 2026

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