Patent ID: 6382798
Filing Date: 2002-05-07
Classification: G02B,H04N

Abstract:
An optical device for projection display system comprising:a display image forming means (3) for forming a display image to be projected on a screen(2), a luminescent spot projector (1) for forming a luminescent spot on the screen(2), a luminescent spot extracting means (4) for extracting light from the luminescent spot out of a reflected light from the screen, a luminescent spot detecting means (5) for detecting a reflected luminescent spot upon receiving the light from the luminescent spot extracting means, a luminescent control means (7) responsive to a detection signal representing the luminescent spot detected by the luminescent spot detecting means, for controlling a display image forming operation of the display image forming means based on the detection signal characterised in that the luminescent spot extracting means (4) is an holographic mirror optically processed at, at least one wavelength of the luminescent spot projector.