Compensation system for CRT deflection errors - uses sensor output to adjust field strength of correction magnets within beam deflection system

摘要

The compensation system uses correction magnets (KM) with differing field strengths integrated in the CRT deflection system (A). The image obtained on the CRT screen is detected via a one-dimensional or 2-dimensional measuring sensor (SLS, EPS) respectively positioned along the lines of symmetry or at the corners of a mask corresponding to the image screen geometry. The measured values obtained are used to control the field strength of the correction magnets (KM) via a setting device. Pref. the field strength of each correction magnet (KM) is reduced by use of an opposite polarity magnetic field obtained via a capacitor battery with a variable storage energy. USE - For automatic correction of CRT deflection errors.