Rear projection viewing screen for close viewing

Claim 2

A rear projection viewing screen, comprising the combination of: a composite Fresnel lens structure including a plastic convex spherical Fresnel lens and a plastic convex cylindrical Fresnel lens arranged in superposed contacting relation; a light-transmitting plastic sheet member having a lenticulated face and a plane face, said lenticulated face comprising a plurality of convex lenticular elements and arranged in superposed spaced relation to said composite Fresnel lens structure; and means securing said lenses and said sheet member in said relations.

Claim 3

The rear projection viewing screen according to claim 1, wherein said spherical Fresnel lens comprises: A second plastic convex cylindrical Fresnel lens; a third plastic convex cylindrical Fresnel lens of the same focal length as said second cylindrical Fresnel lens, said second and third cylindrical Fresnel lenses fixedly arranged in crossed relatIon.

Claim 4

The rear projection viewing screen according to claim 1, wherein the three of said cylindrical Fresnel lenses are of the same focal length.

Claim 5

The rear projection viewing screen according to claim 1, wherein said spherical Fresnel lens comprises: a second light-transmitting plastic sheet member having first and second faces, said first face describing a convex cylindrical Fresnel lens pattern, said second face describing a convex cylindrical Fresnel lens pattern having the same focal length as the Fresnel lens pattern of said first face, said cylindrical Fresnel lens patterns of said first and second faces being in crossed relation.

Claim 6

The rear projection viewing screen according to claim 1, wherein said cylindrical Fresnel lens includes a longitudinal axis, and said lenticulated face comprises a plurality of convex cylindrically lenticular elements arranged substantially parallel to said longitudinal axis.

Claim 7

The rear projection viewing screen according to claim 1, wherein said cylindrical Fresnel lens includes a longitudinal axis, said lenticulated face comprises a plurality of convex cylindrically lenticular elements arranged substantially parallel to said longitudinal axis, and said sheet member further includes masking means on said plane face, said masking means having light-transmitting areas therein corresponding to and coextensive with said cylindrically lenticular elements and positioned to intercept focused light rays emanating from the screen.

Claim 8

The rear projection viewing screen according to claim 1, wherein said lenticulated face comprises a plurality of convex spherically lenticular elements.

Claim 9

The rear projection viewing screen according to claim 1, wherein said lenticular face comprises a plurality of convex spherically lenticular elements, and said sheet member further includes masking means on said plane face, said masking means having light-transmitting areas therein corresponding to said spherically lenticular elements and positioned to intercept focused light rays emanating from the screen.

Claim 10

A rear projection viewing screen, comprising the combination of: a first light-transmitting plastic sheet member having first and second faces, said first face describing a cylindrical Fresnel lens pattern having a first longitudinal axis and said second face describing a cylindrical Fresnel lens pattern having a second longitudinal axis substantially perpendicular to said first longitudinal axis, said Fresnel lens patterns having the same focal length; a second light-transmitting plastic sheet member having a face describing a convex cylindrical Fresnel lens pattern including a third longitudinal axis, said second sheet member arranged in superimposed contacting relation to said first sheet member; a third light-transmitting plastic sheet member having a lenticulated face and a plane face, said lenticulated face comprising a plurality of convex lenticular elements arranged in superposed spaced relation to said second sheet member, said third sheet member including masking means on said plane face, said masking means having light-transmitting areas therein corresponding to said lenticular elements and positioned to intercept focused light rays emanating from the screen; and, means securing said sheet members in said relations.

Claim 11

A rear projection viewing screen, comprising the combination of: a first light-transmitting plastic sheet member having first and second faces, said first face describing a cylindrical Fresnel lens pattern having a first longitudinal axis and said second face describing a cylindrical Fresnel lens pattern having a second longitudinal axis substantially perpendicular to said first longitudinal axis, said Fresnel lens patterns having the same focal length; a second light-transmitting plastic sheet member having a face describing a convex cylindrical Fresnel lens pattern including a third longitudinal axis, said second sheet member arranged in superimposed contacting relation to said first sheet member; a third light-transmitting plastic sheet member having a lenticulated face and a plane face, said lenticulated face comprising a plurality of convex lenticular elements arranged in superposed spaced relation to said second sheet member, said third sheet member including masking means on said plane face, said masking means having light-transmitting areas therein corresponding to said lenticular elements and positioned to intercept focused light rays emanating from the screen; and, means securing said sheet members in said relations.

Claim 12

The rear projection viewing screen according to claim 9, wherein all of said cylindrical Fresnel lens patterns are of the same focal length.

Claim 13

The rear projections viewing screen according to claim 9, wherein said lenticulated face comprises a plurality of convex cylindrically lenticular element substantially arranged parallel to said third longitudinal axis.

Claim 14

The rear projection viewing screen according to claim 9, wherein said lenticulated face comprises a plurality of convex spherically lenticular elements.

Claim 15

The rear projection viewing screen according to claim 9, wherein said second longitudinal axis is perpendicular tO said third longitudinal axis.

Claim 16

The rear projection viewing screen according to claim 9, wherein said second longitudinal axis is perpendicular to said third longitudinal axis, and said second longitudinal axis is acentric on said second sheet member.

Claim 17

A rear projection viewing screen, comprising the combination of: a composite Fresnel lens structure including a first plastic convex cylindrical Fresnel lens and a second plastic convex cylindrical Fresnel lens arranged in crossed relation; a light-transmitting plastic sheet member having a lenticulated face and a plane face, said lenticulated face comprising a plurality of convex lenticular elements and arranged in superposed spaced relation to said composite Fresnel lens structure; and means securing said lenses and said sheet member in said relations.

Claim 18

A rear projection viewing screen, comprising the combination of: a composite Fresnel lens structure including a first plastic convex cylindrical Fresnel lens and a second plastic convex cylindrical Fresnel lens arranged in crossed relation; a light-transmitting plastic sheet member having a lenticulated face and a plane face, said lenticulated face comprising a plurality of convex lenticular elements and arranged in superposed spaced relation to said composite Fresnel lens structure; and means securing said lenses and said sheet member in said relations.

Claim 19

The rear projection viewing screen according to claim 15, wherein said first and second cylindrical Fresnel lenses have respectively different focal lengths.

Claim 20

The rear projection viewing screen according to claim 15, wherein said first and second cylindrical Fresnel lenses have the same focal length, said composite Fresnel lens structure further including a third plastic convex cylindrical Fresnel lens arranged in superposed contacting relation with said second cylindrical Fresnel lens.

Claim 21

In a rear projection viewing screen, a composite Fresnel lens structure comprising the combination of: three plastic convex cylindrical Fresnel lenses in superposed successively contacting relation and having respective longitudinal axes, the longitudinal axes of two of said lenses being substantially perpendicular to the longitudinal axis of the third of said lenses but rotationally displaced therefrom by equal amounts and in opposite directions.

Claim 22

In a rear projection viewing screen, a composite Fresnel lens structure comprising the combination of: three plastic convex cylindrical Fresnel lenses in superposed successively contacting relation and having respective longitudinal axes, the longitudinal axes of two of said lenses being substantially perpendicular to the longitudinal axis of the third of said lenses but rotationally displaced therefrom by equal amounts and in opposite directions.