Interlaced scanning

Interlaced scanning: In raster-scanned video displays, a scanning technique in which all odd-numbered scanning lines are first traced in succession, followed by the tracing of the even-numbered scanning lines in succession, each of which is traced between a pair of odd-numbered scanning lines.

Note 1: The pattern created by tracing the odd-numbered scanning lines is called the "odd field" , and the pattern created by tracing the even-numbered scanning lines is called the "even field" . Each field contains half the information content, i.e., pixels, of the complete video frame.

Note 2: Image flicker is less apparent in an interlaced display than in a noninterlaced display, because the rate at which successive fields occur in an interlaced display is twice that at which successive frames would occur in a noninterlaced display containing the same number of scanning lines and having the same frame refresh[?] rate. Synonym interlacing.

Source: from Federal Standard 1037C