Projector

Abstract

The invention is to provide a projector capable of preventing formation of a ghost image resulting from multiple reflection caused by a synthesizing optical system. The projector 10 prevents the reflection characteristics of a pair of dichroic films 61 and 62 from being overlapped or superposed. Accordingly, the boundary light BL of blue light LB or green light LG entering a cross dichroic prism 60 is prevented from becoming return light made incident on a liquid crystal panel 51g or the like as a result of being double-reflected by both the dichroic films 61 and 62. Specifically, this prevents the problem that, as in the case where the dichroic films 61 and 62 have the reflection characteristics overlapping each other, return light is turned into an advancing light as a result from being reflected by a liquid crystal panel 51b or the like, and ends up forming a ghost image or the like on the screen SC with such advancing light.

Description

Technical field [0001] The present invention relates to a projector that projects an image using a light modulation device such as a liquid crystal panel. Background technique [0002] As a conventional projector, there is one in which image light of each color emitted from a liquid crystal panel of each color illuminated by blue, red, and green illuminating light passes through a pair of multi-layer films for blue and red reflection and arranged in an X shape. A projector in which a synthesis optical system performs color synthesis (see Patent Documents 1, 2, 3, 4, and 5). In the above projector, the blue image light is reflected by the multi-layer film for blue reflection, the red image light is reflected by the multi-layer film for red reflection, and the green image light is spread on the two multi-layer films. When the light is transmitted, the image light is superimposed, that is, color synthesis is performed (see Patent Documents 1, 2, 3, 4, and 5). [0003] Among them, in...

AI Technical Summary

Problems solved by technology

[0011] However, in the case of a projector using a synthetic optical system having a multilayer film for blue reflection and a multilayer film for red reflection, the lighting device for illuminating liquid crystal panels of each color is subject to a structure in which green light is branched at the center. limits

That is, in this synthetic optical system, it is limited by the configuration of the optical path that makes the green image light straight and combines the blue or red image light from both sides, so it is difficult to realize, for example, that the light that is opposed to the green optical path is arranged on the green optical path. Chengchang's relay optical system projector

[0012] In addition, in the projector with the relay optical system arranged on the green optical path, although the multilayer film for blue or red reflection and the multilayer film for green reflection constitute the dichroic prism as the synthetic optical system, but for example, the green The image light at the border wavelength of blue forms a double image on the screen due to multiple reflections on the two multilayer films

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