High performance projection display with two light valves
First Claim
1. Apparatus for selectively directing a plurality of color components of light from a light source into a plurality of different directions, comprising:
- means for separating light from the light source into the plurality of color components and also into different polarization states; and
means for directing each of the different polarization states and plurality of color components into said plurality of different directions.
3 Assignments
0 Petitions
Accused Products
Abstract
A simplified two-light valve configuration for high performance projection displays which eliminates much complexity and the costs associated with three-light valve projection displays, such as a crossed dichroic beam splitter cube, a long retrofocus projections lens, and the additional cost and complexity of a third light valve. Two reflective liquid crystal light valves are positioned and aligned relative to each other on two adjacent surfaces of a polarizing beam splitter cube. Illumination is introduced through a third face of the cube, and a projection lens images the two light valves through a fourth surface of the polarizing beam splitter cube. Color-sequential and alternating polarization states are provided by a color filter wheel or cage containing individual facets of dichroic or color glass filters, such that as the wheel or cage rotates, the filters change and produce sequential red, green and blue outputs. In addition, the polarization of adjacent colors is alternated by adding a polarizing film onto each color filter.
143 Citations
20 Claims
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1. Apparatus for selectively directing a plurality of color components of light from a light source into a plurality of different directions, comprising:
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means for separating light from the light source into the plurality of color components and also into different polarization states; and means for directing each of the different polarization states and plurality of color components into said plurality of different directions. - View Dependent Claims (2)
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- 3. A projection display system having first and second light valves, a polarizing beam splitter wherein the polarizing beam splitter transmits a portion of a light beam to operate one light valve only in transmission and reflects a portion of the light beam to operate the other light valve only in reflection, a projection lens, and means for projecting a color and polarization sequence of illumination of three colors, wherein any two sequential colors have perpendicular polarization states.
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18. A time sequential projection system to project rapid-rate video images, comprising:
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a) first and second light valves, and beam splitting and combining optics to deliver light from either of said first and second light valves to a projection lens; b) an illumination subsystem for sequentially projecting beams of different primary colors onto the first and second light valves, with each light valve alternately projecting a single color component of a frame while the other light valve is being reset for the next color component. - View Dependent Claims (19, 20)
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Specification