Turning film having multiple slopes
US7957082B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 2007 |
| Grant date | Jun 7, 2011 |
| Priority date | — |
| Expiry date | Nov 15, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/045
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention provides a light redirecting article for redirecting light toward a target angle, the light redirecting article comprising: an input surface comprising a plurality of light redirecting structures each light redirecting structure having a near surface having two slopes, sloping away from normal in one direction as defined by a first inclination base angle β1, a second inclination angle β2, and a first half apex angle α2, for accepting incident illumination over a range of incident angles and a far surface sloping away from normal, in the opposite direction relative to the input surface, as defined by a second base angle γ1 and a second half apex angle α1. The invention further provides an output surface opposing to the input surface wherein the near and far surfaces are opposed to each other at an angle (α1+α2) that is in the range from 60 to 70 degrees, and the base angle β1 is in the range from 82 to 87 degrees.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.