An optical projection system has a display cell that is configured to project a display image in response to light striking the display cell. The system has a light source that is configured to project a beam of light and a lens array that is positioned to intercept the beam and generate multiple beamlets...http://www.google.com.au/patents/US5924783?utm_source=gb-gplus-sharePatent US5924783 - System for controlling contrast in projection displays
