Corner-cube retroreflectors for displays
First Claim
1. A system for enhancing a contrast ratio of flat panel displays that utilize selectively controlled frustrated total internal reflection to turn pixels on and off, comprising:
- a plurality of movable elements, operable for frustration of total internal reflection by way of suitable matching of refractive index between the plurality of movable elements and a waveguide in which total internal reflected light is trapped; and
a plurality of corner-cube retroreflector structures added to a surface of each of the plurality of movable elements comprising a pixel, such that a vertex of each of the plurality of corner-cube retroreflector structures is oriented to face the waveguide in which total internal reflected light is trapped and available for selectively controllable frustration, entailing optical coupling and subsequent emission toward an observer'"'"'s eye, wherein facets forming each of the plurality of corner-cube retroreflectors are at right angles to one another, and wherein each vertex of the plurality of corner-cube retroreflector structures is truncated and flattened so as to form a flat planar surface, nominally in a shape of an equilateral triangle, parallel to a surface of the waveguide, such that each said flat planar surface is in spaced-apart relation to the waveguide when the pixel is in its quiescent state at a distance sufficiently large to prevent frustration of total internal reflected light within the waveguide, and is propelled in tandem with a main body of the movable element into contact or near-contact in an active state of the pixel, thus frustrating total internal reflection and causing the pixel to emit optical energy heretofore trapped in the waveguide by selectively controllable means.
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Accused Products
Abstract
Enhancement of the contrast ratio of optical flat panel displays by integrating an array of corner-cube retroreflectors into the front face of the optical display, said integration involving mutual adaptation of both the display and the corner-cube retroreflector geometry to unite the two disparate optical systems. The light emission from the display passes through the truncated vertex of the corner-cubes to the observer. The display directs its emitted light through the vertex apertures (either as a natural behavior, or by interposing a registered array of light concentrators between the display and the corner-cube array). The improvement in contrast ratio arises due to the corner-cube retroreflectors'"'"' ability to direct incident ambient light directly back to its source, rather than the viewer'"'"'s eyes. Ambient light reflections are not attenuated but maximized; this maximization is directed away from the viewer, causing the array to appear dark even in direct sunlight.
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Citations
21 Claims
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1. A system for enhancing a contrast ratio of flat panel displays that utilize selectively controlled frustrated total internal reflection to turn pixels on and off, comprising:
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a plurality of movable elements, operable for frustration of total internal reflection by way of suitable matching of refractive index between the plurality of movable elements and a waveguide in which total internal reflected light is trapped; and a plurality of corner-cube retroreflector structures added to a surface of each of the plurality of movable elements comprising a pixel, such that a vertex of each of the plurality of corner-cube retroreflector structures is oriented to face the waveguide in which total internal reflected light is trapped and available for selectively controllable frustration, entailing optical coupling and subsequent emission toward an observer'"'"'s eye, wherein facets forming each of the plurality of corner-cube retroreflectors are at right angles to one another, and wherein each vertex of the plurality of corner-cube retroreflector structures is truncated and flattened so as to form a flat planar surface, nominally in a shape of an equilateral triangle, parallel to a surface of the waveguide, such that each said flat planar surface is in spaced-apart relation to the waveguide when the pixel is in its quiescent state at a distance sufficiently large to prevent frustration of total internal reflected light within the waveguide, and is propelled in tandem with a main body of the movable element into contact or near-contact in an active state of the pixel, thus frustrating total internal reflection and causing the pixel to emit optical energy heretofore trapped in the waveguide by selectively controllable means. - View Dependent Claims (2, 3, 4, 5, 6)
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7. A system for enhancing a contrast ratio of flat panel displays that utilize conventional transmissive or emissive approaches to image generation, comprising:
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a plurality of non-imaging transparent light concentrator structures to collect light emitted or transmitted from a display surface and funnel it, by way of concentration, into small apertures at a focusing tip of said concentrator structure; and a plurality of corner-cube retroreflector structures on a surface of the display, such that vertices of the corner-cube retroreflector structures are oriented to face the display, wherein facets forming each of the plurality of corner-cube retroreflector structures are at right angles to one another, and wherein vertices of each of the plurality of corner-cube retroreflector structures are truncated so as to form a flat planar surface, nominally in a shape of an equilateral triangle, each of which is parallel to a surface of the display, such that focusing tips of the plurality of non-imaging transparent light concentrator structures are mated to the vertices. - View Dependent Claims (8, 9, 10, 11, 12)
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- 13. A system for enhancing a contrast ratio of a display that utilizes conventional transmissive or emissive approaches to image generation comprising a plurality of coplanar corner-cube retroreflector structures added to a surface of the display, such that vertices of the plurality of coplanar corner-cube retroreflector structures are oriented to face the display, wherein facets forming the corner-cube retroreflector structures of corner-cube retroreflector structures are truncated so as to form a flat planar surface, nominally in a shape of an equilateral triangle, each of which is parallel to the surface of the display, such that a plane defined by the equilateral triangle truncated surfaces is in contact, or in near contact, with the display.
Specification