Patent ID: 7845802
Filing Date: 2010-12-07
Classification: G03B,H04N

Abstract:
1. An illumination apparatus provided with a first polarization conversion element configured to align polarization directions of first color component light, second color component light, third color component light and fourth color component light; a first light valve configured to modulate the first color component light; a second light valve configured to modulate at least the second color component light; a third light valve configured to modulate at least the third color component light; a fourth light valve configured to rotate a polarization direction of the fourth color component light; and a color combining unit configured to combine the first color component light outputted from the first light valve, output light including at least the second color component light outputted from the second light valve, and output light including at least the third color component light outputted from the third light valve, comprising: a first separation optical element of plate-like shape in which a first dichroic surface and a first polarization separation surface are formed, the first dichroic surface is configured to reflect the second color component light and to transmit the third color component light, and the first polarization separation surface is configured to transmit polarization component light of a certain polarization direction and to reflect polarization component light of a different polarization direction perpendicular to the certain polarization direction, wherein the second color component light and the third color component light, the polarization directions of which have been aligned by the first polarization conversion element, enter the first separation optical element from a certain direction, and the fourth color component light, the polarization direction of which has been rotated by the fourth light valve, enters the first separation optical element from a different direction, the first separation optical element combines the third color component light entering the first dichroic surface from the certain direction and transmitted through the first dichroic surface, with the fourth component light entering the first polarization separation surface from the different direction and reflected by the first polarization separation surface, and leads a combined light towards the third light valve, and the first separation optical element combines the second color component light entering the first dichroic surface from the certain direction and reflected by the first dichroic surface with the fourth color component light entering the first polarization separation surface from the different direction and transmitted through the first polarization separation surface, and leads a combined light towards the second light valve.