Patent · US Expired

Method for determining an optimum gain response in a spatial frequency response correction for a projection system

US7224849B2 · kind B2 · utility

4Cited by
6References
51Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 7, 2003
Grant dateMay 29, 2007
Priority date
Expiry dateOct 29, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/3194
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method for determining an optimum gain response in a spatial frequency correction for a projection system comprises the steps of setting a code value (100) to a first code value; projecting a flat field image at the code value; capturing the flat field image (540) with a camera; creating a defect map (70) of defects in the flat field image; applying the defect map to the flat field image to form a corrected image; setting a gain table (80) to a first gain for the corrected image; applying the gain table to the corrected image; registering the corrected image; filtering the registered image; measuring the filtered image for a standard deviation (570); determining whether all gains for producing an under corrected image (60) and an over corrected image have been exhausted for the code value; if all gains have not been exhausted for the code value, set the gain table to the first gain plus n and go to the step of applying the gain table to the corrected image, if all gains have been exhausted go to determining an optimum gain for the code value.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.