Patent ID: 8657449
Filing Date: 2014-02-25
Classification: G03B

Abstract:
1. A projection type display apparatus comprising: a first and a second illumination light source devices; an image display element; an illumination optical system having a plurality of optical elements which illuminates the image display element with light from the first and the second illumination light source devices; and a projection lens which enlarges an optical image formed by the image display element and projects the enlarged image; wherein the illumination optical system has first array lens and second array lens each of which has a plurality of lens elements arranged in a matrix form, each lens having a rectangular shape opening and; wherein the first and the second illumination light source devices each has a pair of light source units configured by combining a light source of P polarized light having a polarization degree greater than 50% and a light source of S polarized light having a polarization degree greater than 50%, a polarizing prism which transmits one type polarized light and reflects other type polarized light, and a polarization conversion element; wherein the first and a second illumination light source devices are arranged such that the polarization directions of light fluxes having high polarization degrees becomes perpendicular to each other, light fluxes from the first light source unit of the first illumination light source device and from the second light source unit of the second illumination light source device are combined by the polarizing prism, among the combined light fluxes a polarization direction of the light flux from any one of the first light source unit or the second light source unit is changed such that a polarization direction of the light flux becomes perpendicular to a polarization direction of the light flux before changed by the polarization conversion element; and wherein the light flux from the first illumination light source device is P polarized light, the light flux from the second illumination light source device is S polarized light, the light fluxes are combined by the polarizer which transmits P polarized light and reflects S polarized light and provided in a subsequent stage of the first and second illumination light source devices, the light fluxes are condensed to a single region by a light-flux condensing means, and then directed toward the illumination optical system located in a subsequent stage.