Music video by Justin Bieber performing Never Let You Go. (C) 2010 The Island Def Jam Music Group. #VEVOCertified on November 9, 2010. http://www.youtube.com/vevocertified.
Lumens are a unit of measurement of the total brightness that comes from a light source, in this case, a projector. One may also see the term ANSI Lumens. ANSI is an acronym for the American National Standards Institute. In general, the more lumens a projector has, the brighter the image on the screen.
A projector or image projector is an optical device that projects an image (or moving images) onto a surface, commonly a projection screen. Most projectors create an image by shining a light through a small transparent lens, but some newer types of projectors can project the image directly, by using lasers.