Faced with the choice of a projector for a large conference room, university lecture theatre, corporate auditorium,...
A standard white wall or a traditional matte-white projector screen is diffuse. This means it reflects light uniformly in every single direction. When your projector's beam hits ay of the two, the image bounces back to your eyes beautifully. However, if you open the blinds or turn on an overhead ceiling light, that ambient light also hits the white wall and bounces into your eyes. Because the wall treats all light equally, the ambient room light mixes with your projector's light. The result?...