Solid state light sheet for general illumination
US8338199B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2010 |
| Grant date | Dec 25, 2012 |
| Priority date | — |
| Expiry date | Aug 27, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/857
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A solid state light sheet and method of fabricating the sheet are disclosed. In one embodiment, bare blue-light LED chips have top and bottom electrodes, where the bottom electrode is a large reflective electrode. The bottom electrodes of an array of LEDs (e.g., 500 LEDs) are bonded to an array of electrodes formed on a flexible bottom substrate. Conductive traces are formed on the bottom substrate connected to the electrodes. In one embodiment, an intermediate sheet having holes is then affixed to the bottom substrate, with the LEDs passing through the holes. A transparent top substrate having conductors is then laminated over the intermediate sheet. In another embodiment, no intermediate sheet is used. Various ways to connect the LEDs in series are described along with many embodiments. The light sheet provides a practical substitute for a standard 2×4 foot fluorescent ceiling fixture. A phosphor is used to generate white light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.