Lightweight low-loss refractive light diffusion system

Claim 2

A light system comprising: a light source adapted to illuminate an area; and at least two refracting substantially transparent and coextensive films juxtaposed with one another and interposed between said source and said area, said films having mutually confronting patterns of refracting rises formed on respective surfaces of said films, said rises being separated by intervening recesses and the rises and recesses being so oriented as to form diversely distributed light-refraction paths across said films, said patterns being selected so that gaps are provided between said films and to effect diffusion of light from said source cast upon said area, said patterns being tessellations of substantially planar polygons having groups of concentric striations parallel to sides of the polygons and said striations are of substantially trapezoidal, triangular or curved cross section.

Claim 3

The light system defined in claim 1 wherein said source is elongated and said rises of at least one film are in the form of longitudinal striations.

Claim 4

A light system comprising: a light source adapted to illuminate an area; and at least two refracting substantially transparent and coextensive films juxtaposed with one another and interposed between said source and said area, said films having mutually confronting patterns of refracting rises formed on respective surfaces of said films, said rises being separated by intervening recesses and the rises and recesses being so oriented as to form diversely distributed light-refraction paths across said films, said patterns being selected so that gaps are provided between said films and to effect diffusion of light from said source cast upon said area, said patterns being tessellations of polyhedra with planar or curved facets or tessellations of substantially planar polygons having groups of concentric striations parallel to sides of the polygons, said films being peripherally interconnected to form a diffusion screen.

Claim 5

A light system comprising: a light source adapted to illuminate an area; and at least two refracting substantially transparent and coextensive films juxtaposed with one another and interposed between said source and said area, said films having mutually confronting patterns of refracting rises formed on respective surfaces of said films, said rises being separated by intervening recesses and the rises and recesses being so oriented as to form diversely distributed light-refraction paths across said films, said patterns being selected so that gaps are provided between said films and to effect diffusion of light from said source cast upon said area, said patterns being tessellations of polyhedra with planar or curved facets or tessellations of substantially planar polygons having groups of concentric striations parallel to sides of the polygons, said films being peripherally interconnected to form a diffusion screen.

Claim 6

The light system defined in claim 3 wherein said patterns are embossed in only one surface of each of said films and said films have smooth planar surfaces turned away from one another.

Claim 7

The light system defined in claim 3 wherein said films have gas-filled spaces between them.

Claim 8

The light system defined in claim 5 wherein said films are flexible, said screen being expandable by gas pressurization of said gas-filled spaces.

Claim 9

The light system defined in claim 3 wherein said films have evacuated spaces between them.

Claim 10

The light system defined in claim 3 wherein said rises of said films bear upon one another to hold said films in position in said screen.

Claim 11

The light system defined in claim 3 wherein at least one of said films is formed with projections independent of the respective rises, projecting beyond the respective rises and engaging the other of said films to hold said films in position in said screen.

Claim 12

The light system defined in claim 3 wherein said patterns on said surfaces are identical but laterally offset from one another.

Claim 13

The light system defined in claim 3 wherein said patterns on said surfaces are complementary but laterally offset from one another.

Claim 14

The light system defined in claim 3 wherein rises of one of said films fit into recesses of the other of said films.

Claim 15

The light system defined in claim 3 wherein said patterns are tessellations of four-sided or six-sided regular polyhedra with planar or curved facets.

Claim 16

The light system defined in claim 13 wherein said polyhedra have projections formed on apexes of said polyhedra.

Claim 17

The light system defined in claim 3, further comprising a planar array of spacers interposed between said surface of said films and holding them apart.

Claim 18

The light system defined in claim 3 wherein said rises are convexly curved.

Claim 19

The light system defined in claim 3 wherein said rises are concavely curved.

Claim 20

The light system defined in claim 3 wherein said patterns have the same or different polygons or polyhedra or, in each pattern, the same or different polygons or polyhedra which can include circular arcs.

Claim 21

The light system defined in claim 3 wherein one of said patterns is a tessellation of faceted polyhedra while the other of said patterns is a tessellation of striated polygons, both of said tessellations having the same period.

Claim 22

The light system defined in claim 3 wherein both of said patterns have the same periodicity.

Claim 23

A light system comprising: a light source adapted to illuminate an area; and at least two refracting substantially transparent and coextensive films juxtaposed with one another and interposed between said source and said area, said films having mutually confronting patterns of refracting rises formed on respective surfaces of said films, said rises being separated by intervening recesses and the rises and recesses being so oriented as to form diversely distributed light-refraction paths across said films, said patterns being selected so that gaps are provided between said films and to effect diffusion of light from said source cast upon said area, said patterns being tessellations of polyhedra with planar or curved facets or tessellations of substantially planar polygons said source being elongated, and said polyhedra or said polygons being elongated in a direction parallel to a direction of elongation of said source.

Claim 24

A light system comprising: a light source adapted to illuminate an area; and at least two refracting substantially transparent and coextensive films juxtaposed with one another and interposed between said source and said area, said films having mutually confronting patterns of refracting rises formed on respective surfaces of said films, said rises being separated by intervening recesses and the rises and recesses being so oriented as to form diversely distributed light-refraction paths across said films, said patterns being selected so that gaps are provided between said films and to effect diffusion of light from said source cast upon said area, said patterns being tessellations of polyhedra with planar or curved facets or tessellations of substantially planar polygons said source being elongated, and said polyhedra or said polygons being elongated in a direction parallel to a direction of elongation of said source.

Claim 25

The light system defined in claim 21 wherein said source is a row of lights, and said polyhedra or said polygons being elongated in a direction parallel to said row.