VIDEO PROJECTOR ILLUMINATION SYSTEM USING TWO LAMPS HAVING COMPLEMENTARY BEAMS PATTERNS

摘要

An apparatus for providing uniform high efficiency illumination in a projection display system comprising two lamp sources each having a different geometric aligning means. By combining a first light source having an annular cross-sectioned beam and a second light source having a circular cross-sectioned beam sized to be identical to said annulus, a light beam is created that provides more light and greater beam uniformity than has heretofore been available using low cost components. The annular beam is produced by a first lamp apparatus having a rear spherical reflector and a front parabolic reflector oriented along an optical axis. The circular beam is produced by a second lamp apparatus having a front spherical reflector and a rear parabolic reflector and having an orientation orthogonal to said optical axis. When the two beams are combined at an oval-shaped flat reflector positioned at a 45° angle to the optical axis, a complementary beam is formed which provides a highly efficient and uniformly distributed light source.