Projection screen

Claim 2

A projection screen for displaying optical images projected thereonto by a projector comprising a multiplicity of optical cells, each of said cells comprising a spherical convex lightconverging lens having a predetermined radius of curvature, means disposed coaxially of an optical axis of said lens and adjacent the focal region thereof for selectively passing those light rays converged by said lens along lines passing through the focal region thereof, said light-passing means including a generally circular surface of light-passing medium disposed generally perpendicular to an optical axis of said lens, mask means including an opaque film of light-absorbing material adhered to predetermined ones of the surfaces of said cell for selectively absorbing those light rays converged by said lens along lines extending through points laterally offset from said focal region, said light-passing surface having a size and shape corresponding to the pattern traced by said first mentioned light rays as the projector is moved a predetermined distance along an axis parallel to and laterally offset from said focal region, and means optically aligned with said light-passing means for dispersing those light rays passed by said light passing means, said cells being secured together in juxtaposition in a position wherein said lenses define a surface.

Claim 3

The screen of claim 1 wherein each of said cells is secured in the screen in a position wherein the optical axes of all of said lenses pass through a common point.

Claim 4

The screen of claim 2 wherein said screen is formed to conform to the contour of a portion of a sphere.

Claim 5

The screen of claim 2 wherein said screen is formed to conform to the contour of a portion of a cylindeR.

Claim 6

A projection screen for displaying optical images projected thereonto by a projector comprising a multiplicity of optical cells, each of said cells comprising a cylindrical light-converging lens having a predetermined radius of curvature, means disposed coaxially of an optical axis of said lens and adjacent to the focal region thereof for selectively passing those light rays converged by said lens along lines passing through the focal region thereof, said light-passing means including a surface of light-passing medium disposed generally perpendicular to an optical axis of said lens, said light-passing surface having the shape of a line of finite width, mask means including an opaque film of light-absorbing material adhered to predetermined ones of the surfaces of said cell for selectively absorbing those light rays converged by said lens along lines extending through points laterally offset from said focal region, said light-passing surface having a size and shape corresponding to the pattern traced by said first mentioned light rays as the projector is moved a predetermined distance along an axis parallel to and laterally offset from said focal region, and means optically aligned with said light-passing means for dispersing those light rays passed by said light passing means, said cells being secured together in juxtaposition in a position wherein said lenses define a surface.

Claim 7

A projection screen for displaying optical images projected thereonto by a projector comprising a multiplicity of optical cells, each of said cells comprising a cylindrical light-converging lens having a predetermined radius of curvature, means disposed coaxially of an optical axis of said lens and adjacent to the focal region thereof for selectively passing those light rays converged by said lens along lines passing through the focal region thereof, said light-passing means including a surface of light-passing medium disposed generally perpendicular to an optical axis of said lens, said light-passing surface having the shape of a line of finite width, mask means including an opaque film of light-absorbing material adhered to predetermined ones of the surfaces of said cell for selectively absorbing those light rays converged by said lens along lines extending through points laterally offset from said focal region, said light-passing surface having a size and shape corresponding to the pattern traced by said first mentioned light rays as the projector is moved a predetermined distance along an axis parallel to and laterally offset from said focal region, and means optically aligned with said light-passing means for dispersing those light rays passed by said light passing means, said cells being secured together in juxtaposition in a position wherein said lenses define a surface.

Claim 8

The screen of claim 5 wherein said light-passing surface is a transparent, generally circular window, said screen further comprising a multiplicity of second optical cells optically overlying said first mentioned optical cells, each of said second cells including a convex, cylindrical lens having its focal line disposed in optically orthogonal relationship with respect to the focal lines of said first cells, said light-dispersing means including a plurality of discrete areas of light-scattering particles coincident with said transparent windows, said windows being disposed on those surfaces of said first mentioned optical cells oppositely disposed from the lens surfaces thereof and coaxially of lines extending perpendicular to the focal lines of said first and said second cells and through the point of intersection thereof.

Claim 9

A projection screen for displaying optical images projected thereonto by a projector comprising a multiplicity of optical cells, each of said cells comprising a light-converging lens having a predetermined radius of curvature, means disposed coaxially of an optical axis of the said lens and adjacent to the focal region thereof for selectively passing those light rays converged by said lens along lines passing through the focal region thereof, said light-passing means including a concave reflecting surface disposed generally perpendicular to an optical axis of said lens, mask means including an opaque film of light-absorbing material adhered to predetermined ones of the surfaces of said cell for selectively absorbing those light rays converged by said lens along lines extending through points laterally offset from said focal region, and means optically aligned with said light-passing means for dispersing those light rays passed by said light-passing means, said cells being secured together in juxtaposition in a position wherein said lenses define a surface.

Claim 10

A projection screen for displaying optical images projected thereonto by a projector comprising a multiplicity of optical cells, each of said cells comprising a light-converging lens having a predetermined radius of curvature, means disposed coaxially of an optical axis of the said lens and adjacent to the focal region thereof for selectively passing those light rays converged by said lens along lines passing through the focal region thereof, said light-passing means including a concave reflecting surface disposed generally perpendicular to an optical axis of said lens, mask means including an opaque film of light-absorbing material adhered to predetermined ones of the surfaces of said cell for selectively absorbing those light rays converged by said lens along lines extending through points laterally offset from said focal region, and means optically aligned with said light-passing means for dispersing those light rays passed by said light-passing means, said cells being secured together in juxtaposition in a position wherein said lenses define a surface.

Claim 11

The screen of claim 7 wherein said lens is spherical and said concave reflecting surface is a spherical mirror, said mirror being positioned coaxially of the optical axis of said lens and optically behind said focal region by a dimension equal to the focal length of said spherical mirror, said passed light rays being rendered parallel by said mirror.

Claim 12

The screen of claim 7 wherein said lens is cylindrical and said concave reflecting surface is a cylindrical mirror, said mirror being positioned with its focal region coincident with the focal region of said cylindrical lens, said passed light rays being rendered parallel thereby.

Claim 13

A projection screen for displaying optical images projected thereonto bY a projector comprising a multiplicity of optical cells, each of said cells comprising a light-converging lens having a predetermined radius of curvature, means disposed coaxially of an optical axis of the said lens and adjacent to the focal region thereof for selectively passing those light rays converged by said lens along lines passing through the focal region thereof, said light-passing means including a surface of light-passing medium disposed generally perpendicular to an optical axis of said lens, mask means including an opaque film of light-absorbing material adhered to predetermined ones of the surfaces of said cell for selectively absorbing those light rays converged by said lens along lines extending through points laterally offset from said focal region, and means optically aligned with said light-passing means for dispersing those light rays passed by said light-passing means, said light-dispersing means including a film of translucent light-scattering particles disposed coaxially of an optical axis of said lens, said film having an area substantially smaller than the surface area of said lens, said cells being secured together in juxtaposition in a position wherein said lenses define a surface.

Claim 14

A projection screen for displaying optical images projected thereonto bY a projector comprising a multiplicity of optical cells, each of said cells comprising a light-converging lens having a predetermined radius of curvature, means disposed coaxially of an optical axis of the said lens and adjacent to the focal region thereof for selectively passing those light rays converged by said lens along lines passing through the focal region thereof, said light-passing means including a surface of light-passing medium disposed generally perpendicular to an optical axis of said lens, mask means including an opaque film of light-absorbing material adhered to predetermined ones of the surfaces of said cell for selectively absorbing those light rays converged by said lens along lines extending through points laterally offset from said focal region, and means optically aligned with said light-passing means for dispersing those light rays passed by said light-passing means, said light-dispersing means including a film of translucent light-scattering particles disposed coaxially of an optical axis of said lens, said film having an area substantially smaller than the surface area of said lens, said cells being secured together in juxtaposition in a position wherein said lenses define a surface.

Claim 15

The screen of claim 10 wherein said light-dispersing means has a size and shape of generally the same shape of said light-passing surface.

Claim 16

The screen of claim 10 wherein said light-dispersing film has a size and shape corresponding to the pattern traced by the cross-section of said passed light rays in the plane including said light-dispersing film as the projector is moved along an axis parallel to and laterally offset from an optical axis of said lens.

Claim 17

The screen of claim 7 wherein said light-dispersing means includes a film of translucent light-scattering particles disposed coaxially of an optical axis of said lens and on the surface thereof.

Claim 18

The screen of claim 13 wherein the focal lines of all of the optical cells extend radially outwardly from the axis of projection of the screen.

Claim 19

A projection screen for displaying optical images projected thereonto by a projector comprising a generally planar body of homogeneous, light-absorbing material having a lens surface and a parallel, spaced-apart back surface, said lens surface including a multiplicity of juxtaposed convex lens portions, said back surface having thereon a multiplicity of upstanding protrusions, each said protrusion having at least one side surface and a distal end surface, there being one of said protrusions for each convex lens portion, each said protrusion being disposed generally coaxially of the focal region of the corresponding one of said lens portions, means coincident with the distal end surfaces of said protrusions for selectively passing those light rays incident on said lens surfaces in a direction essentially parallel to the optical axes thereof, mask means including a film of light-absorbing material adhered to said back surface and said side surfaces of absorbing those light rays incident on said lens surface at oblique angles to the optical axes of said lens portions, and means optically aligned with said light passing means for dispersing those light rays passed by said light passing means.

Claim 20

A projection screen for displaying optical images projected thereonto by a projector comprising a generally planar body of homogeneous, light-absorbing material having a lens surface and a parallel, spaced-apart back surface, said lens surface including a multiplicity of juxtaposed convex lens portions, said back surface having thereon a multiplicity of upstanding protrusions, each said protrusion having at least one side surface and a distal end surface, there being one of said protrusions for each convex lens portion, each said protrusion being disposed generally coaxially of the focal region of the corresponding one of said lens portions, means coincident with the distal end surfaces of said protrusions for selectively passing those light rays incident on said lens surfaces in a direction essentially parallel to the optical axes thereof, mask means including a film of light-absorbing material adhered to said back surface and said side surfaces of absorbing those light rays incident on said lens surface at oblique angles to the optical axes of said lens portions, and means optically aligned with said light passing means for dispersing those light rays passed by said light passing means.

Claim 21

The screen of claim 15 wherein said lens portions are generally spherical and said protrusions are cylindrical.

Claim 22

The screen of claim 15 wherein said lens portions are generally cylindrical and said protrusions are elongated ridges of rectangular cross-sections.

Claim 23

For use in a projection screen for displaying optical images projected thereonto by a projector, an optical cell comprising a generally rectangular block of optically transparent material having a convex lens surface and an oppositely disposed back mask surface, said back mask surface being generally parallel to and spaced apart from said lens surface by a predetermined dimension, the focal length of said lens surface being equal to or shorter than said predetermined dimension, said back mask surface having a film of opaque, light-absorbing material adhered thereto, a surface of light-passing material disposed coaxially of an optical axis of said lens and extending in a direction generally perpendicular thereto, the size and shape of said light-passing surface corresponding to the cross-section of those light rays converged by said lens surface along lines passing through the focal region thereof, whereby said light-passing surface selectively passes only those light rays incident upon said lens surface in a direction generally parallel to the line of projection thereof and said mask surface selectively absorbs those light rays incident upon said lens surface at oblique angles to said line of projection, and light-dispersing means disposed in optical alignment with and optically behind said light-passing surface for receiving and scattering light rays passed thereby.

Claim 24

For use in a projection screen for displaying optical images projected thereonto by a projector, an optical cell comprising a generally rectangular block of optically transparent material having a convex lens surface and an oppositely disposed back mask surface, said back mask surface being generally parallel to and spaced apart from said lens surface by a predetermined dimension, the focal length of said lens surface being equal to or shorter than said predetermined dimension, said back mask surface having a film of opaque, light-absorbing material adhered thereto, a surface of light-passing material disposed coaxially of an optical axis of said lens and extending in a direction generally perpendicular thereto, the size and shape of said light-passing surface corresponding to the cross-section of those light rays converged by said lens surface along lines passing through the focal region thereof, whereby said light-passing surface selectively passes only those light rays incident upon said lens surface in a direction generally parallel to the line of projection thereof and said mask surface selectively absorbs those light rays incident upon said lens surface at oblique angles to said line of projection, and light-dispersing means disposed in optical alignment with and optically behind said light-passing surface for receiving and scattering light rays passed thereby.