Patent ID: 6132047
Filing Date: 2000-10-17
Classification: G02B,H04N

Abstract:
A polarized light illumination apparatus comprising:a polarized light separating optical element including: a) a first polarization separating film that separates light incident from a first direction into two types of polarized light, transmits one of the two types of polarized light and directs the transmitted one type of polarized light in a third direction, and reflects another of the two types of polarized light and directs the reflected other type of polarized light in a fourth direction, and b) a second polarization separating film that separates light incident from a second direction into two types of polarized lights, reflects one of the two types of polarized lights and directs the reflected one type of polarized light in said fourth direction, and transmits another of the two types of polarized lights and directs the transmitted other type of polarized light in a fifth direction;a first light source that emits the light incident on said polarized light separating optical element from said first direction;a second light source that emits the light incident on said polarized light separating optical element from said second direction;a first condensing and reflecting optical element including a plurality of small condensing and reflecting elements, that substantially reverses a traveling direction of the light emerging in said third direction form said polarized light separating optical element and forms a plurality of condensed light images;a second condensing and reflecting optical element including a plurality of small condensing and reflecting elements that substantially reverses a traveling direction of the light emerging in said fifth direction from said polarized light separating optical element and forms a plurality of condensed light images;a reflecting optical element that substantially reverses a traveling direction of the light emerging in said fourth direction form said polarized light separating optical element;a first polarization-state conversion optical element disposed between said polarized light separating optical element and said first condensing and reflecting optical element;a second polarization-state conversion optical element disposed between said polarized light separating optical element and said second condensing and reflecting optical element;a third polarization-state conversion optical elements disposed between said polarized light separating optical element and said reflecting optical elements; anda polarization conversion optical elements that makes uniform direction of polarization of the light emerging from said polarized light separating optical element in a sixth direction,a center axis of the light which is incident on said polarization conversion optical elements after being reflected by said small condensing and reflecting elements of said first condensing and reflecting optical element and a center axis of the light which is incident on said polarization conversion optical element after being reflected by said small condensing and reflecting elements of said second condensing and reflecting optical element being substantially parallel to each other and not overlapping each other,said reflecting optical element being disposed such that the light emitted from said first light source and then reflected by said first polarization separating film is incident on said second light source and the light emitted from said second light source and then reflected by said second polarization separating film is incident on said first light source.