Illumination systems employing laminated sheet-form optical structures with embedded TIR channels
An illumination system comprising a lighting module with a plurality of LEDs, a flexible optically transmissive sheet disposed in an energy-receiving relationship with the lighting module, and broad-area reflective surface configured to reflectively scatter light. The flexible optically transmissive sheet has a laminated structure with a generally rectangular shape and a thickness between 200 micrometers and 1 millimeter. The laminated structure comprises a first layer of an optically transmissive material, a second layer of an optically transmissive material, a first regular array of linear channels formed in the first layer extending parallel to one another between two edges of the flexible optically transmissive sheet, and a second regular array of linear channels formed in the second layer extending at an angle with respect to the first regular array of linear channels. The linear channels define side walls configured to reflect light using total internal reflection.
1 . An illumination system, comprising:
a lighting module comprising a plurality of LEDs;
a flexible optically transmissive sheet disposed in an energy receiving relationship with respect to the lighting module, the flexible optically transmissive sheet having a laminated structure with a generally rectangular shape and a thickness between 200 micrometers and 1 millimeter, the laminated structure comprising:
a first layer of an optically transmissive material,
a second layer of an optically transmissive material,
a first regular array of linear channels formed in the first layer and extending parallel to one another between two edges of the flexible optically transmissive sheet, and
a second regular array of linear channels formed in the second layer and extending at an angle with respect to the first regular array of linear channels between two edges of the flexible optically transmissive sheet; and
a broad-area reflective surface configured to reflectively scatter light,
wherein each of the linear channels in the first and second regular arrays defines a pair of side walls configured to reflect light using total internal reflection.
2 . An illumination system as recited in claim 1 , wherein the angle is approximately 90 degrees.
3 . An illumination system as recited in claim 1 , wherein the laminated structure further comprises a surface having a light diffusing texture.
4 . An illumination system as recited in claim 1 , further comprising a light diffusing film.
5 . An illumination system as recited in claim 1 , further comprising a collimating lens positioned on a light path between the lighting module and the flexible optically transmissive sheet.
6 . An illumination system as recited in claim 1 , further comprising a beam shaping lens positioned on a light path between the lighting module and the flexible optically transmissive sheet.
7 . An illumination system as recited in claim 1 , wherein at least some of the linear channels of the first regular array are separated from one another by surface portions of the first layer which are generally parallel to the first layer, and wherein at least some of the surface portions are disposed in contact with the second layer.
8 . An illumination system as recited in claim 1 , wherein each of the linear channels of the first regular array is formed in a surface of the first layer which is facing the second layer, wherein the first regular array of linear channels defines a parallel array of linear structures protruding away from the first layer, and wherein at least some of the linear structures are bonded to the second layer using an optically transmissive adhesive material.
9 . An illumination system as recited in claim 1 , comprising a surface having a microlens pattern.
10 . An illumination system as recited in claim 1 , wherein at least one dimension of the laminated structure is greater than 1 meter.
11 . An illumination system as recited in claim 1 , wherein a largest dimension of the laminated structure is at least 0.5 meters.
12 . An illumination system as recited in claim 1 , wherein a largest dimension of the laminated structure is at least 0.2 meters.
13 . An illumination system as recited in claim 1 , wherein the flexible optically transmissive sheet is retained in a curved shape.
14 . An illumination system as recited in claim 1 , wherein the first regular array of linear channels is configured with variable spacing.
15 . An illumination system as recited in claim 1 , comprising a material configured to alter color of transmitted light.
16 . An illumination system as recited in claim 1 , comprising a layer configured to filter specific wavelengths of light.
17 . An illumination system as recited in claim 1 , comprising a sheet of glass disposed in energy receiving relationship with respect to the flexible optically transmissive sheet.
18 . An illumination system, comprising:
a light source comprising a plurality of LEDs;
a first layer of an optically transmissive material;
a second layer of an optically transmissive material superimposed on and bonded to the first layer using an optically transmissive adhesive;
a first linear array of parallel channels formed in the first layer;
a second linear array of parallel channels formed in the second layer;
an optical sheet comprising a two-dimensional pattern of light diffusing surface microstructures; and
a broad-area reflective surface configured to reflectively scatter light,
wherein the second linear array of parallel channels extends at an angle with respect to the first linear array of parallel channels,
wherein the first linear array of parallel channels defines a plurality of linear prismatic surface structures protruding away from the first layer and longitudinally extending along straight parallel lines from a first edge of the first layer to a different second edge of the first layer,
wherein each of the plurality of linear prismatic surface structures has a first wall and a second wall contiguous with the first wall and disposed at a right angle with respect to the first wall,
wherein the first wall is configured to reflect light using total internal reflection, and
wherein the first layer and the second layer form a flexible laminated sheet-form structure having a generally rectangular shape and a thickness between 200 micrometers and 1 millimeter.
19 . An illumination system, comprising:
a light source comprising a plurality of LEDs;
a first layer of an optically transmissive material;
a second layer of an optically transmissive material superimposed on and bonded to the first layer using an optically transmissive adhesive;
a first linear array of parallel channels formed in the first layer and longitudinally extending along straight parallel lines from a first edge of the first layer to a different second edge of the first layer;
a second linear array of parallel channels formed in the second layer and longitudinally extending along straight parallel lines at an angle with respect to the parallel channels of the first linear array;
an optical sheet comprising a two-dimensional pattern of light diffusing surface microstructures; and
a broad-area reflective surface configured to reflectively scatter light,
wherein at least some of the parallel channels formed in the first layer are separated from one another by surface portions which are generally parallel to a plane of the first layer,
wherein each of the parallel channels of the first linear array has a surface which is disposed at an angle with respect to a plane of the first layer and is configured to reflect light using total internal reflection, and
wherein the first layer and the second layer form a flexible laminated sheet-form structure having a generally rectangular shape and a thickness between 200 micrometers and 1 millimeter.
20 . An illumination system as recited in claim 18 , wherein the angle is approximately 90 degrees.
21 . An illumination system as recited in claim 18 , wherein the first linear array of parallel channels is configured with variable spacing.
22 . An illumination system as recited in claim 18 , wherein a largest dimension of the flexible laminated sheet-form structure is at least 0.5 meters.
23 . An illumination system as recited in claim 18 , wherein at least some of the parallel channels of the first linear array are separated from one another by surface portions of the first layer which are generally parallel to a plane of the first layer, and wherein at least some of the surface portions are disposed in contact with the second layer.
24 . An illumination system as recited in claim 18 , wherein a largest dimension of the flexible laminated sheet-form structure is at least 0.5 meters, and wherein the flexible laminated sheet-form structure is retained in a curved shape.
25 . An illumination system as recited in claim 18 , further comprising a beam shaping lens positioned on a light path between the light source and the flexible laminated sheet-form structure.
26 . An illumination system as recited in claim 18 , further comprising a sheet of glass disposed in energy receiving relationship with respect to the flexible laminated sheet-form structure.
27 . An illumination system as recited in claim 18 , further comprising a material configured to alter color of transmitted light.
28 . An illumination system as recited in claim 18 , further comprising a layer configured to filter specific wavelengths of light.
29 . An illumination system as recited in claim 18 , further comprising a surface having a lens pattern.
30 . An illumination system as recited in claim 18 , further comprising a sheet of glass disposed in energy receiving relationship with respect to the flexible laminated sheet-form structure, wherein a largest dimension of the flexible laminated sheet-form structure is at least 0.5 meters, and wherein the flexible laminated sheet-form structure is retained in a curved shape.
31 . An illumination system as recited in claim 18 , wherein the first linear array of parallel channels is configured with variable spacing, wherein at least some of the parallel channels of the first linear array are separated from one another by surface portions of the first layer which are generally parallel to a plane of the first layer, and wherein at least some of the surface portions are disposed in contact with the second layer.
32 . An illumination system as recited in claim 19 , wherein the angle is approximately 90 degrees.
33 . An illumination system as recited in claim 19 , wherein the first linear array of parallel channels is configured with variable spacing, and wherein at least some of the surface portions are disposed in contact with and bonded to the second layer using the optically transmissive adhesive.
34 . An illumination system as recited in claim 19 , further comprising a sheet of glass disposed in energy receiving relationship with respect to the flexible laminated sheet-form structure, wherein a largest dimension of the flexible laminated sheet-form structure is at least 0.5 meters.
35 . An illumination system as recited in claim 19 , wherein at least some of the surface portions are disposed in contact with and bonded to the second layer using the optically transmissive adhesive.
36 . An illumination system as recited in claim 19 , further comprising a sheet of glass disposed in energy receiving relationship with respect to the flexible laminated sheet-form structure, wherein a largest dimension of the flexible laminated sheet-form structure is at least 0.5 meters, and wherein the flexible laminated sheet-form structure is retained in a curved shape.
37 . An illumination system as recited in claim 19 , further comprising a beam shaping lens positioned on a light path between the light source and the flexible laminated sheet-form structure.
38 . An illumination system as recited in claim 19 , further comprising a surface having a lens pattern.
39 . An illumination system as recited in claim 19 , further comprising a material configured to alter color of transmitted light.