Also found in: Medical.
helical scanning[′hel·ə·kəl ′skan·iŋ]
A method of facsimile scanning in which a single-turn helix rotates against a stationary bar to give horizontal movement of an elemental area.
A method of recording on videotape and digital audio tape in which the tracks are recorded diagonally from top to bottom by wrapping the tape around the rotating-head drum in a helical path.
A method of radar scanning in which the antenna beam rotates continuously about the vertical axis while the elevation angle changes slowly from horizontal to vertical, so that a point on the radar beam describes a distorted helix.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.