FLAT INDEX TYPE COLOR IMAGE REPRODUCING DEVICE

摘要

PURPOSE:To uniformly improve the color purity over the entire picture while using chroma scanning by controlling the amplitude of a chroma signal corresponding to the difference in horizontal deflection snsitivity on the positions of vertical scanning. CONSTITUTION:In a chroma scan circuit 6, an index signal from an index signal processing circuit 3 is processed, and a color signal current whose frequency is equal to the repeating frequency (triplet frequency) of RGB fluorescent body arrays which flows through a flat index tube 1 and a chroma scanning signal having a specific phase relation, are formed. The circuit 6, further, controls the amplitudes of said signals based on a vertical saw-tooth signal form a high-voltage deflection circuit 5, then applying the chroma scan signal to a sub-deflection yoke 10 in order, the horizontal scan speed is modulated. The chroma scanning can be executed by making the chroma scanning amplitude smaller in the initial part of the vertical scan and larger in the ending part of the same. In such a way, the purity of color can be improved by means of the chroma scan in every part of the vertical scanning.