Horizontal shift clock pulse selection circuit use of driving color LCD screen

Abstract

An influence of a switching noise caused by a horizontal shift clock to an oscillation frequency of a voltage controlled oscillator should be eliminated, to prevent an image shift in a PAL skip period. For this purpose, an odd number line horizontal shift clock from an odd number line horizontal shift clock generator and an even number line horizontal shift clock from an even number line horizontal shift clock generator are switched by a horizontal shift clock switching circuit, to be input to a color LCD panel. The horizontal shift clock switching circuit selects and outputs either the odd number line horizontal shift clock or the even number line horizontal shift clock according to a line identifying signal, in a normal period. By contrast, in a PAL skip period a selecting state of the shift clock is inverted immediately upon start of a PAL skip period, from a selecting state right before the start of the skip period, and the selecting state is again inverted in half a cycle of a horizontal scanning period.

Description

technical field [0001] The present invention relates to a color liquid crystal panel driving horizontal shift clock pulse selection circuit for driving video signals of a color liquid crystal panel. In particular, it relates to a horizontal shift clock selection circuit for driving a color liquid crystal panel for necessary skip driving in the PAL system. Background technique [0002] In terms of the pixel arrangement of the color LCD panel, some pixel arrangements are staggered by 0.5 pixels in each row, such as figure 2 The shown triangular-arranged color liquid crystal panels and pixel arrays are color liquid crystal panels arranged vertically in linear stripes. The invention is a circuit for driving triangularly arranged color liquid crystal panels in a PAL system. [0003] In order to drive a color liquid crystal panel in a triangular arrangement, a pulse for selecting a pixel must set a horizontal shift clock according to the pixel arrangement. exist image 3 The o...

AI Technical Summary

Problems solved by technology

Therefore, in the image display of the triangular-arranged color liquid crystal panel, the following phenomenon occurs: the image misalignment occurs in the next line after jumping, and even if a signal that should be displayed as a vertical straight line is input to the color liquid crystal panel, the display is not displayed. in a straight line

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