Patent ID: 6185047
Filing Date: 2001-02-06
Classification: G02B,H04N

Abstract:
In an image display system that includes a light source from which a first light beam characterized by a first principal ray propagates in a first direction and a reflective light modulator which responds to a control signal to selectively change an optical property of incident light derived from the first light beam and thereby provide an information-carrying light beam for display on a display screen, the improvement comprising:an angle-dependent beam separator comprised of multiple optical elements, the beam separator positioned to receive the first light beam and constructed so that an incident light beam derived from the first light beam propagates along a first travel path within the beam separator and strikes the reflective light modulator at an angle of incidence, the reflective light modulator responding to the control signal to selectively reflect the incident light beam at a controlled angle of reflection that differs from the angle of incidence of the incident light beam to provide an on-state reflected light beam that propagates along a second travel path within the beam separator and exits the beam separator to form a second light beam characterized by a second principal ray that propagates in a second direction, the optical elements having shapes and surface angles that cause the first and second travel paths and the first and second principal rays of the respective first and second light beams not to lie in a common plane.