Center convergence optimization in a projection display apparatus

Abstract

Progressive rounding error and convergence error encountered due to multiple use of a center correction adjustment (820) of an image of a video projection display is reduced by calculating a 3 x 3 matrix (770) for a moved color signal where the non center matrix values represent the difference between the initially measured sensor values (Si1,...,Si8) stored at initial alignment (720), and stored most recently measured sensor values (Sp1,...,Sp8). The matrix center value (860) is the sum of the averaged values calculated from the edge center errors, the stored sum of previous moves (MS) and the current move (CP). Rerun of the sensor finding routine (745) resets the stored move sum to zero.

Description

[0001] This application claims priority under U.S.C. Section 35 119(e) to U.S. Provisional Application No. 60 / 399,865, filed July 31, 2002, entitled "Centre Convergence Optimization in Projection Display Devices." technical field [0002] This invention relates to the field of video projection displays and, in particular, to the correction of minor convergence errors at the center of the projected image following automatic convergence correction. Background technique [0003] In video projection displays, geometric raster distortion is due to the physical location of the cathode ray display tube. This raster distortion is exacerbated by the use of display surfaces with concave curvature and the inherent magnification in the light projection channel. The projected image consists of three scanned rasters that need to be aligned with each other on the display. Precise superposition of the three projected images requires adjustment of multiple wavelengths to compensate for geom...

AI Technical Summary

Problems solved by technology

If multiple such centering adjustments are made without re-running the sensor, which finds a routine that eras

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