Patent ID: 7570258
Filing Date: 2009-08-04
Classification: G09G,H04N

Abstract:
1. A method for adjusting at least one of a scanning frequency and a scanning phase of an analog/digital converter of an image-reproducing device, wherein the image-reproducing device has a digitally controlled display for displaying an image of a predefined number of lines and a predefined number of pixels per line; wherein the digitally controlled display receives digital image data from the analog/digital converter; wherein the analog/digital converter generates the digital image data by scanning with a scanning signal having the scanning frequency and the scanning phase of a predefined analog video signal; and wherein the digital image data is buffered in an image memory; the method comprising: applying the predefined analog video signal to the image-reproducing device; comparing the digital image data buffered in the image memory with predefined data that corresponds to the predefined analog video signal; changing the scanning frequency until the comparison of the digital image data with the predefined data results in a predetermined match; detecting a respective brightness value in a pixel by means of the scanning signal; measuring the respective brightness value; increasing the scanning phase of the scanning signal until the brightness value of the pixel changes so as to determine a first boundary value; resetting an original phase; subsequently decreasing the original phase until the brightness value of the pixel changes again so as to determine a second boundary value; and adjusting the scanning phase of the scanning signal so as to correspond to an average value of the first and second boundary values, wherein a predetermined number of consecutive pixels of a line of the test image is checked for a match with the predefined data.