active infrared detection system

active infrared detection system

[′ak·tiv ′in·frə‚red di′tek·shən ‚sis·təm]
(engineering)
An infrared detection system in which a beam of infrared rays is transmitted toward possible targets, and rays reflected from a target are detected.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.