Illumination system employing an array of microprisms
First Claim
1. An illumination assembly for providing a spatially-directed light source comprising:
- (a) a light transmitting means having a first light accepting surface in close proximity to a first diffuse light source, wherein said light transmitting means transports light emanating from said first diffuse light source;
(b) an array of microprisms wherein each microprism comprises;
(i) a light input surface optically coupled to said light transmitting means;
(ii) a first pair of oppositely disposed sidewalls wherein at least one of said sidewalls forms a first tilt angle with respect to the normal of the surface of said light transmitting means; and
(iii) a second pair of oppositely disposed tilted sidewalls wherein at least one of said sidewalls forms a second tilt angle with respect to the normal of the surface of said light transmitting means; and
(c) a low index of refraction layer disposed between said light transmitting means and said light input surfaces;
wherein, a first portion of said light reflecting through said light transmitting means enters said array of microprisms through said light input surfaces, is redirected by said sidewalls and emerges from said microprisms as a spatially-directed light source and a second portion of said light reflecting through said light transmitting means is prevented from entering said light input surfaces by said low index of refraction layer.
3 Assignments
0 Petitions
Accused Products
Abstract
An optical illumination system comprising a waveguide that accepts light generated by a diffuse light source and transmits the light via total internal reflection. Attached on one surface of the waveguide is a low index of refraction layer and an array of microprisms, with each microprism having an light input surface and at least one sidewall tilted at an angle from the direction normal to the surface of the waveguide such that light escapes from the waveguide, reflects off the tilted sidewalls and emerges from the microprism as a spatially-directed light source. The low index of refraction layer prevents low angle light from entering the microprisms. An array of microlenses may be positioned to accept the output of the microprisms so that the light exiting from the microlenses is a substantially collimated light source. The optical illumination system is advantageous for any application that requires a non diffuse or substantially collimated that is both energy efficient and contained in a low profile assembly.
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Citations
23 Claims
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1. An illumination assembly for providing a spatially-directed light source comprising:
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(a) a light transmitting means having a first light accepting surface in close proximity to a first diffuse light source, wherein said light transmitting means transports light emanating from said first diffuse light source; (b) an array of microprisms wherein each microprism comprises; (i) a light input surface optically coupled to said light transmitting means; (ii) a first pair of oppositely disposed sidewalls wherein at least one of said sidewalls forms a first tilt angle with respect to the normal of the surface of said light transmitting means; and (iii) a second pair of oppositely disposed tilted sidewalls wherein at least one of said sidewalls forms a second tilt angle with respect to the normal of the surface of said light transmitting means; and (c) a low index of refraction layer disposed between said light transmitting means and said light input surfaces; wherein, a first portion of said light reflecting through said light transmitting means enters said array of microprisms through said light input surfaces, is redirected by said sidewalls and emerges from said microprisms as a spatially-directed light source and a second portion of said light reflecting through said light transmitting means is prevented from entering said light input surfaces by said low index of refraction layer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. An illumination assembly for providing a spatially-directed light source comprising:
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(a) a light transmitting means having a first light accepting surface in close proximity to a first diffuse light source, and a second light accepting surface in close proximity to a reflecting means for reflecting light generated by said first diffuse light source wherein said light transmitting means transports light emanating from said first diffuse light source; (b) an array of microprisms wherein each microprism comprises; (i) a light input surface optically coupled to said light transmitting means; (ii) a light output surface having a surface area greater than the surface area of said light input surface; (iii) first pair of oppositely disposed sidewalls wherein each of said sidewalls forms a first tilt angle to the normal of the surface of said light transmitting means; (iv) a second pair of oppositely disposed tired sidewalls wherein each of said sidewalls forms a second tilt angle to the normal of the surface of said light transmitting means; and (c) a low index of refraction layer disposed between said light transmitting means and said light input surface; wherein, a first portion of said light reflecting through said light transmitting means enters said array of microprisms through said light input surfaces, is redirected by said sidewalls and emerges from said microprisms as a spatially-directed light source and a second portion of said light reflecting through said light transmitting means is prevented from entering said light input surfaces by said low index of refraction layer and is recycled within said waveguide by said reflecting means and enters said array of microprisms through said light input surfaces, is redirected by said sidewalls and emerges from said microprisms as a spatially-directed light source. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22, 23)
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Specification