Color-recombination glass prism

Abstract

This invention relates to combination prism integrated by different color, which comprises two right angle prism with one inclination coated with bias oscillator film and two right angle prism glued into end top in rectangle prism, wherein, one right angle prism surface is added with one quarter wavelet, band pass filter slice, one quarter wavelet; the above bias split film has reflection bias as S light and P bias light function; the band filter pass is coated by glass base board with one wave band to reflect other wave section light function.

Description

technical field [0001] The invention relates to a combination prism for synthesizing different color lights, which is used for synthesizing three different color polarized lights, and belongs to the field of optical technology. Background of the invention [0002] In liquid crystal (LCD) or liquid crystal on silicon (LCOS) projection systems, in order to achieve color display, it is necessary to combine the three primary color polarized lights from three optical paths into one optical path. [0003] In the prior art, the color combining prism adopts more X prisms, such as Chinese invention patent: the application number is 99104851.2 "light selection prism, projection display with the prism and method for manufacturing the prism". The X prism is usually made of four right-angle prisms glued along the right-angle surface, and the slope of the right-angle prism is used as the input surface and output surface of the light. The red, green and blue primary color polarized light ...

AI Technical Summary

Problems solved by technology

Its disadvantages are: (1) The design and gluing of the four right-angle prisms and the film system that make up the X prism have strict requirements, such as the angular tolerance of the prisms is often controlled within a few arc seconds; (2) For right-angle There are very high requirements for the processing of right-angled edges of prisms, and no damage is allowed during processing, let alone chamfering; (3) The four right-angled edges must be strictly aligned during gluing, and the gluing ridgeline should be well controlled Otherwise, the glued ridge line will appear in the image field of view and affect the image quality; (4) Another difficulty in the manufacture of X prisms is the coating of the color-combining film. For polarized light films, it is usually necessary to use the Brewster angle , at this angle, it is relatively easy to achieve the transmission of P-polarized light and the reflection of S-polarized light, but for the X prism, no matter how the incident position and polarization state of the three primary colors are arranged, it is inevitable that the transmission of S-polarized light will inevitably occur. Or the case of reflecting P polarized light, which increases the design and production requirements of the film, thereby increasing the cost

[0004] In addition, an L-shaped color combination prism is also used in the liquid crystal projector, such as the Chinese utility model patent: "New Combination Prism Color Light Decomposition and Synthesis Device" with application number 97201084.X, the L-type color combination prism consists of 3 This kind of dichroic prism eliminates the glue line of the X prism, but it has a large volume. For the dichromatic film, it also has the disadvantage of requiring reflection of P polarized light or transmission of S polarized light. In addition, this kind of dichroic prism The prism also has the disadvantage of requiring a long back focus of the projection lens

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