Light-emitting diode with diagonal faces
US5087949A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1991 |
| Grant date | Feb 11, 1992 |
| Priority date | — |
| Expiry date | Mar 5, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/82
Abstract
A transparent light-emitting diode has front and back parallel faces and a plurality of side faces perpendicular to the back face. Diagonal faces interconnect each side face with the front face to form a truncated polygonal pyramid surmounting a polygonal base of the light-emitting diode. Because some of the light impinges on the diagonal faces at an angle less than the critical angle for total internal reflection, from 1.5 to 2 times as much light is extracted from the LED as a conventional rectangular LED without the diagonal faces. The diagonal faces on the LEDs are readily made by sawing V-shaped grooves in the front face of a wafer on which the LEDs are fabricated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.