Projector

Abstract

A projector, which has a light source, an optical modulator which modulates a light beam irradiated from the light source in accordance with image information to form an optical image and a projection optical system which projects the formed optical image, includes: an integrator illuminating optical system which equalizes the light beam irradiated from the light source and uniformly illuminates an image formation area of the optical modulator. The integrator illuminating optical system includes: a first lens array having a plurality of first lenses in a plane substantially orthogonal to an optical axis of the light beam irradiated from the light source and divides the light beam into a plurality of partial light beams by the plurality of first lenses, a second lens array having a plurality of second lenses corresponding to the plurality of first lenses of the first lens array, and a polarization converter which is disposed on a light beam emitting-side of the first lens array and aligns a polarization direction of the light beam irradiated from the first lens array into a substantially uniform type. The polarization converter includes: at least one polarization separating layer of which lengthwise direction in a plane substantially orthogonal to the optical axis of the light beam irradiated from the light source is defined as a first direction, the polarization separating layer transmitting polarized light having one polarization direction of an incident light beam and reflects polarized light having another polarization direction, at least one reflection layer which is disposed in a second direction substantially orthogonal to the optical axis of the light beam irradiated from the light source and the first direction such that the polarization separating layer and the reflection layer are alternately arranged in the second direction, the reflection layer reflecting the polarized light reflected by the polarization separating layer into a common direction to that of the polarized light passed through the polarization separating layer, and a phase layer which is disposed at a position corresponding to the polarization separating layer or the reflection layer and converts the polarization direction of the incident polarized light into another polarization direction. A focal position in the first direction of the first lens is set in the vicinity of the second lens array in the optical direction of the light beam irradiated from the first lens. A focal position in the second direction of the first lens is set in the vicinity of the polarization converter in the optical direction of the light beam irradiated from the first lens.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.

FIG. 1 is a schematic illustration briefly showing a structure of a projector of a first exemplary embodiment of the invention;

FIG. 2 is a schematic illustration showing a focal position in a second direction of a first lens of the first exemplary embodiment;

FIG. 3 is a schematic illustration showing a focal position in a first direction of the first lens of the first exemplary embodiment;

FIG. 4 is a schematic illustration showing a structure of a polarization converter of the first exemplary embodiment;

FIG. 5 is an illustration showing an optical path of a light beam in a second direction of a first comparison to the first exemplary embodiment;

FIG. 6 is an illustration showing a portion of FIG. 5 in an enlarged manner;

FIG. 7 is a graph showing a relation between a movement amount in the second direction of a light emitting portion and luminance distribution on a liquid crystal panel of the first comparison to the first exemplary embodiment;

FIG. 8 is an illustration showing an optical path of a light beam in the second direction of the first exemplary embodiment;

FIG. 9 is an illustration showing a portion of FIG. 8 in an enlarged manner;

FIG. 10 is a graph showing a relation between a movement amount in the second direction of a light emitting portion and luminance distribution on a liquid crystal panel of the first exemplary embodiment;

FIG. 11 is a schematic illustration showing a focal position in a second direction of a first lens of a second exemplary embodiment of the invention; and

FIG. 12 is a schematic illustration showing a focal position in a first direction of the first lens of the second exemplary embodiment.

Claims

1. A projector comprising: a light source;an optical modulator that modulates a light beam irradiated from the light source in accordance with image information to form an optical image;a projection optical system that projects the formed optical image; andan integrator illuminating optical system that equalizes the light beam irradiated from the light source and uniformly illuminates an image formation area of the optical modulator, the integrator illuminating optical system including a first lens array having a plurality of first lenses in a plane substantially orthogonal to an optical axis of the light beam irradiated from the light source and dividing the light beam into a plurality of partial light beams by the plurality of first lenses, a second lens array having a plurality of second lenses corresponding to the plurality of first lenses of the first lens array, and a polarization converter disposed on a light beam emitting-side of the first lens array and aligning a polarization direction of the light beam irradiated from the first lens array into a substantially uniform type, the polarization converter includes: at least one polarization separating layer, at least one reflection layer and a phase layer disposed at a position corresponding to either the polarization separating layer or the reflection layer, the lengthwise direction of the polarization separating layer in a plane substantially orthogonal to the optical axis of the light beam irradiated from the light source being defined as a first direction, the polarization separating layer transmitting light having one polarization direction of an incident light beam and reflecting light having another polarization direction, the polarization separating layer and the reflection layer being alternately arranged in a second direction, the second direction being orthogonal to the optical axis of the light beam irradiated from the light source and the first direction, the reflection layer reflecting the polarized light reflected by the polarization separating layer into a common direction to that of the polarized light passed through the polarization separating layer, the phase layer converting the polarization direction of the incident polarized light into another polarization direction, a focal position in the first direction of the first lens being set in the vicinity of the second lens array in the optical axis direction of the light beam irradiated from the first lens, and a focal position in the second direction of the first lens being set in the vicinity of the polarization converter in the optical axis direction of the light beam irradiated from the first lens.

2. The projector according to claim 1, further comprising: a color-separating optical system that separates the light beam irradiated from the integrator illumination optical system into a plurality of color light beams, the optical modulator being provided for each of the plurality of color light beams, and the optical modulators being disposed on each optical path of the plurality of color light beams; andat least one color-combining optical device that combines the plurality of color light beams irradiated from the optical modulators, the color-combining optical device being provided on the downstream of the optical path of the modulator.

3. The projector according to claim 1, the first lens being a toric lens.

4. The projector according to claim 2, the first lens being a toric lens.