flicker

Definition: Rapidly changing, irregular effects seen on computer monitor screens. (1) Apparent variations of shape or position seen with change of display: the change e.g. scrolling or change of viewpoint is faster than the display refresh can keep up. * Frequently seen when LCD screens of digital cameras are used as the viewfinder. (2) Rapid variation of density most visible in even, light areas on a monitor with interlacing, due mainly to low refresh rates. * The maximum rate of variation is roughly the reciprocal of the period of persistence in vision. Flickering hell Flicker in monitors is defect that can cause considerable eye-strain, even when barely noticeable. It is usually cured by using monitors with high refresh rates i.e. at least 70Hz. Note: some LCD screens use flicker to simulate greys: pixels are switched rapidly between black and white. The ratio between the time spent as black and as white determines the shade of grey. It is not very smart way to dither a grey-scale, ergonimically speaking.

Related Terms: interlace

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