Patent ID: 6348997
Filing Date: 2002-02-19
Classification: F21V,G02B,G03B,H04N

Abstract:
A polarizing illumination device comprising:a polarization separating optical element having a first polarization separating film that separates light incident from a first direction into two types of polarized light beams, emits transmitted light in a third direction, and emits reflected light in a fourth direction, and a second polarization separation film that separates light incident from a second direction into two types of polarized light beams, emits reflected light in the fourth direction, and emits transmitted light in a fifth direction; a first light source section that allows light to enter the polarization separating optical element from the first direction; a second light source section that allows light to enter the polarization separating optical element from the second direction; a first condensing-and-reflecting optical element including a plurality of condensing-and-reflecting devices that approximately reverses the direction of travel of the light emitted in the third direction by the polarization separating optical element and forming a plurality of focal images; a second condensing-and-reflecting optical element including a plurality of condensing-and-reflecting devices that approximately reverses the direction of travel of the light emitted in the fifth direction by the polarization separating optical element and forming a plurality of focal images; a reflecting optical element for approximately reverses the direction of travel of the light emitted in the fourth direction by the polarization separating optical element; a first polarization-state conversion optical element disposed between the polarization separating optical element and the first condensing-and-reflecting optical element; a second polarization-state conversion optical element disposed between the polarization separating optical element and the second condensing-and-reflecting optical element; a third polarization-state conversion optical element disposed between the polarization separating optical element and the reflecting optical element; and a polarization conversion optical element that unifies the direction of polarization of the light emitted in a sixth direction from the polarization separating optical element, an approximately central axis of a luminous flux, which is reflected by the condensing-and-reflecting devices of the first condensing-and-reflecting optical element and enters the polarization conversion optical element, and an approximately central axis of a luminous flux, which is reflected by the condensing-and-reflecting devices of the second condensing-and-reflecting optical element and enters the polarization conversion optical element, not being parallel to each other and not overlapping each other.