Patent ID: 6183090
Filing Date: 2001-02-06
Classification: G02B,H04N

Abstract:
A projection type image display apparatus, comprising:a light source;a first polarization selective reflection element having a function of reflecting or transmitting a light beam from the light source in accordance with a polarization direction thereof;a first element for modulating a polarization plane of an incident light beam in accordance with an image to be displayed;a projection lens for projecting the modulated light beam; anda polarizing filter for transmitting only a linearly polarized component of a light beam having one direction, said polarizing filter being located between at least one of the light source and the first polarization selective reflection element, and the first polarization selective reflection element and the protection lens,wherein the first polarization selective reflection element is film-like and has an optical transmission axis and an optical reflection axis,the first polarization selective reflection element transmits a first linearly polarized light beam, and reflects a second linearly polarized light beam having a polarization plane orthogonal to a polarization plane of the first linearly polarized light beam, regardless of a direction of incidence of a light beam with respect to the first polarization selective reflection element,the first polarization selective reflection element has a structure in which a polarization selective reflection film having a polarization selective reflection function is stacked on a polarizing filter for transmitting only a linearly polarized component of a light beam having one direction, the polarization selective reflection film being closer to the first element.