projection perimeter

pro·jec·tion pe·rim·e·ter

a perimeter that uses as target a spot of light that can be adjusted rapidly as to size, brightness, and color, and moves silently at any desired speed.
References in periodicals archive ?
SMU, EDAC; EASYJET; Prayer Room: System maintenance video projection perimeter CDGE:: - Maintenance,: - Modification work, but with increased volume.