Parabolic waveform generating apparatus.

摘要

Horizontal or vertical parabolic waveforms corresponding to arbitrary aspect ratios are generated with a relatively small number of memory devices for storing data values which are used for generating parabolic waveforms to compensate horizontal or vertical deflection distortion in television receivers. A first and second memory device which each store data values for generating parabolic waveforms necessary for the images of a specific aspect ratio (for example, (4:3) and (16:9) are provided. When a desired aspect ratio is given to a logic circuit, two coefficients are calculated in a coefficient arithmetic logic unit and the outputs of the first and the second ROM memory device are allocated proportionally in a logic circuit. The output data values of the logic circuit are then converted to a desired parabolic waveform. <IMAGE>