Light emitting diode with light conversion using scattering optical media
US6614170B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 2001 |
| Grant date | Sep 2, 2003 |
| Priority date | — |
| Expiry date | Aug 11, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention provides a light emitting diode (LED) or other light emitting means such as a laser diode (LD) comprising a light emitting component and scattering optical media such as dielectric phosphor powder (DPP) which absorb a part of light emitted by the light emitting component and emits light of a wavelength that is different from that of the absorbed light. In a preferred embodiment according to the invention, the LED includes a crystalline semiconductor chip serving as the light emitting component. The scattering optical media such as dielectric phosphor powder (DPP) is made of a mixture of phosphor particles and microscopic, nearly spherical dielectric particles with a band gap larger than 3 eV (which do not absorb blue light in the spectrum). The scattering optical media such as DPP can also include phosphor particles, and bubbles (or voids) instead of the dielectric particles. The bubbles of the DPP have a band gap larger than 3 eV which do not absorb blue light in the spectrum. The bubbles can be air bubbles, N2 bubbles, noble gas bubbles. Furthermore, the scattering optical media such as DPP can also be a mixture of the bubbles, dielectric particles, and the phosphor…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.