Illumination system employing an array of microprisms
US5428468A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 1994 |
| Grant date | Jun 27, 1995 |
| Priority date | — |
| Expiry date | May 13, 2014 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21Y2103/00
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
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 face of the waveguide is an array of microprisms, with each microprism having an light input surface parallel to a light output surface and at least two sidewalls 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. 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.