Patent ID: 7379124
Filing Date: 2008-05-27
Classification: H04N

Abstract:
1. A video display apparatus, comprising: a controllable source of a plurality of beams for producing an image on a display screen; a photo sensor responsive to a light produced by said image for generating a light sensing output signal; a source of a centering signal; and a processor responsive to said fight sensing output signal for performing, when selected, an automatic image distortion correction operation to store a first plurality of correction values in a memory, said processor being further responsive to said centering signal and to correction values stored in said memory for producing a second plurality of correction values that are applied to said controllable source of said plurality of beams to provide an image centering change of said image, in accordance with said centering signal, such that, for any possible sequence of image centering operations, a worst case change to a difference between a center of one of a plurality of color bands forming an image on said display screen and a center of one of the other color bands is less than one half of a millimeter.