- A scanning system, such as that of computer monitors, in which the electron beam traces all lines sequentially from top to bottom. This contrasts with interlaced scanning, in which the electron beam traces all odd-numbered lines followed by the tracing of all even-numbered lines. Interlaced scanning may produce a fluttering effect when displaying certain graphics, a drawback not exhibited by a non-interlaced monitor. Also spelled noninterlaced scanning. Also called non-interlaced scan, non-interlacing, progressive scanning, or sequential scanning.