High-contrast front projection video display system

Claim 2

A front-projection video display system for obtaining high contrast in a viewing room without darkened ambient conditions comprising: a front-projection video projector, which projects an image in components, said projected image having an intensity and said components having substantially the same direction of polarization, wherein said front projection video projector produces a projected image comprising three components, a first and a second component having the same polarization and a third component being orthogonally polarized to said first and second components, and wherein said projector comprises a first half-wave plate for rotating said third component into agreement with said first and second components; a polarization maintaining projection screen for receiving said projected image from said video projector; and a polarizing filter located between said video projector and said projection screen, said filter being polarized in the same direction as said components of said projected image, wherein said polarization maintaining screen substantially preserves the intensity of said projected image on roundtrip between said polarizing filter and said screen.

Claim 3

The front-projection video display system of claim 1 wherein said components of said projected image and said polarizing filter are substantially polarized in the horizontal direction.

Claim 4

The front-projection video display system of claim 1 wherein the polarizing filter is tilted forward away from said projection screen to prevent bright reflections from being observed by viewers.

Claim 5

The front-projection video display system of claim 3 wherein the polarizing filter is anti-reflective.

Claim 6

The front-projection video display system of claim 1 wherein said polarizing filter follows the surface of the screen such that the surface reflections from said polarizing filter also form an image which is marginally displaced from the image formed by the surface of said screen, thereby suppressing undesirable effects of specular reflection from said polarizing filter.

Claim 7

The front-projection video display system of claim 1 further comprising polarizing lenses for covering light fixtures within a viewing room, said lenses being polarized orthogonal to said polarizing filter and said components of said projected image such that ambient light radiated from said light fixtures and polarized parallel to said polarized image is substantially blocked at said polarizing lenses and ambient light polarized orthogonal to said projected image is blocked at said polarizing filter for high contrast.

Claim 8

A front-projection video display system for obtaining high contrast in a viewing room without darkened ambient conditions comprising: a front-projection video projector which projects an image in components, said projected image having an intensity and said components having substantially the same direction of polarization, wherein said front projection video projector produces a projected image comprising three components, a first and a second component having the same polarization and a third component being orthogonally polarized to said first and second components, and wherein said projector comprises a first half-wave plate for rotating said third component into agreement with said first and second components; a polarization maintaining projection screen for receiving said projected image from said video projector; a polarizing filter located between said video projector and said projection screen, said filter being polarized in the same direction as said components of said projected image, wherein said polarization maintaining screen substantially preserves the intensity of said projected image on roundtrip between said polarizing filter and said screen; and polarizing lenses for covering light fixtures within the viewing room, said lenses being polarized orthogonal to said polarizing filter and said components of said projected image such that ambient light from the light fixtures and polarized parallel to said polarized image is substantially blocked at said polarizing lenses and ambient light polarized orthogonal to said projected image is blocked at said polarizing filter for high contrast.

Claim 9

A front-projection video display system for obtaining high contrast in a viewing room without darkened ambient conditions comprising: a front-projection video projector which projects an image in components, said projected image having an intensity and said components having substantially the same direction of polarization, wherein said front projection video projector produces a projected image comprising three components, a first and a second component having the same polarization and a third component being orthogonally polarized to said first and second components, and wherein said projector comprises a first half-wave plate for rotating said third component into agreement with said first and second components; a polarization maintaining projection screen for receiving said projected image from said video projector; a polarizing filter located between said video projector and said projection screen, said filter being polarized in the same direction as said components of said projected image, wherein said polarization maintaining screen substantially preserves the intensity of said projected image on roundtrip between said polarizing filter and said screen; and polarizing lenses for covering light fixtures within the viewing room, said lenses being polarized orthogonal to said polarizing filter and said components of said projected image such that ambient light from the light fixtures and polarized parallel to said polarized image is substantially blocked at said polarizing lenses and ambient light polarized orthogonal to said projected image is blocked at said polarizing filter for high contrast.

Claim 10

The front-projection video display system of claim 7 wherein said projector further comprises a second half-wave plate for rotating said first, second, and third components to a particular polarization.

Claim 11

The front-projection video display system of claim 7 wherein said components comprise three different color sub-images.