Method and apparatus for horizontal raster correction for triangular or sinusoidal deflection

摘要

In known cathode-ray picture tubes with triangular or sinusoidal deflection, phase shifts occur between the video signals and the deflection current. It is proposed to fade into the centre of the last forward and return line in each case of each field a reference marker, the position of which on the screen is detected with the aid of sensors, for example of photoelements. The output signals of the sensors are supplied to a reference marker evaluation circuit which emits a correction signal which is proportional to the deviation from the nominal position of the reference markers. This correction signal is used for driving either the read control for a line store or the horizontal output stage. IMAGE