Method for centring and dimensioning an image on a cathode-ray tube

摘要

The steps of the process comprise: (a) measuring (50) the durations (T1HAV, T2HAV) of the vertical black edges of the image and modifying step by step the adjustment (HPOS) for horizontal centering to obtain equal lateral vertical edges; (b) measuring (52) the durations (T1HAV and T2HAV) of the vertical black edges of the image to calculate the adjustment (HSIZE) of the horizontal dimension of the image so as to cause the vertical black edges to disappear; (c) measuring (54) the durations (T1VAV and T2VAV) of the horizontal black edges of the image to calculate the adjustment of the vertical dimension of the image (VSIZE') and the adjustment of the vertical centering of the image (VPOS') so as to cause the horizontal black edges to disappear and to center the image vertically, and (d) recording (56) the adjustment values obtained (HPOS, HSIZE, VSIZE' and VPOS') in a memory of the display calculator.