Screen Corner Convergence Correction
Original Publication Date: 1984-Dec-01
Included in the Prior Art Database: 2005-Feb-06
In-line color CRTs used in display systems require only low precision convergence correction. Parabolic convergence would be required for accurate correction over a whole screen but here a straight line approximation can be used to give correction only at the corners of the screen. The circuits disclosed may be added during manufacture without disturbing components such as neck hardware and without impact on yoke parameters such as purity and sensitivity. This disclosure makes use of the fact that precision yokes from suppliers give the required precision over most of the screen area, needing extra convergence (for certain applications) only in the screen corners. For example, a worst-case convergence error of less than 0.