Flicker : Light that alternately brightens and dims. Flicker on a VDU occurs at between about 50 and 80 times a second and is visible only under certain conditions
Ministry of Business, Innovation and Employment, Glossary of terms and acronyms, Wellington, New Zealand 2010. http://wwwsosh.govt.nz/resources/glossary-u.shtml, (Occupn Hlth and Sfty - Brit) {530}