Patent ID: 6348996
Filing Date: 2002-02-19
Classification: F21V,G02B,G03B,H04N

Abstract:
A polarizing illumination device, comprising:a first light source section and a second light source section; a polarization-separating-and-synthesizing optical element comprising a first polarizing separation film for transmitting, of light emitted from the first light source section, a linear polarized light polarized in a direction parallel to an incident surface thereof and reflecting a linear polarized light polarized in a direction perpendicular to the incident surface, and a second polarizing separation film for transmitting, of light emitted from the second light source section, a linear polarized light polarized in a direction perpendicular to an incident surface thereof and reflecting a linear polarized light polarized in a direction parallel to the incident surface; a first condensing-and-reflecting optical element comprising a plurality of condensing-and-reflecting devices that approximately reverse the direction of travel of the linear polarized light transmitted by the first polarizing separation film and form focal images; a second condensing-and-reflecting optical element comprising a plurality of condensing-and-reflecting devices that approximately reverse the directions of travel of the linear polarized lights reflected by the first polarizing separation film and the second polarizing separation film and form focal images; a third condensing-and-reflecting optical element including a plurality condensing-and-reflecting optical devices that approximately reverse the direction of travel of the linear polarized light transmitted by the second polarizing separation film and form focal images; a first polarization-state conversion optical element disposed between the polarization-separating-and-synthesizing optical element and the first condensing-and-reflecting optical element; a second polarization-state conversion optical element disposed between the polarization-separating-and-synthesizing optical element and the second condensing-and-reflecting optical element; a third polarization-state conversion optical element disposed between the polarization-separating-and-synthesizing optical element and the third condensing-and-reflecting optical element; and a polarization conversion optical element that unifies the polarization directions of linear polarized lights synthesized by the polarization-separating-and-synthesizing 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 the third 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.