Optical architectures for combining multiple lamps in light valve projectors

This invention relates to the field of display systems, more particularly to display systems using multiple light sources in combination with a spatial light modulator. An integrating rod () for combining light beams from two or more sources. A first light beam () enters the integrating rod through a first entrance face () to a first reflecting face (). The light is reflected by the first reflecting face () and travels along the major axis () of the integrating rod () to an exit face (). A second light beam () from a second light source enters the integrating rod () through a second entrance face (). The second light beam may be reflected by a second reflecting face () and travels along the major axis () to the exit face (). The two light beams experience multiple reflections as they travel along the integrating rod and leave the integrating rod () through the exit face () as a single homogenous light beam.