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A method of displaying a video image by tracing out alternate scan-lines in successive fields. (A field is a single complete scanning of the screen.) When alternate lines have been traced out, the scanning spot flies back to the top of the screen to trace out the remaining lines in the spaces between those of the first descent. This allows a lower refresh rate (and lower bandwidth requirements for lower frame rate) to produce an image that appears flicker-free. While this is true of most pictorial content and interlacing is still an essential feature of television, it is seldom now used in computer displays since a single horizontal line can appear to flicker at half the frame frequency. Higher speed graphics cards and monitors have generally replaced interlacing to produce high-quality displays.

Subjects: Computing.

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