Phosphor layer containing transparent particles over blue LED
US8772814B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2013 |
| Grant date | Jul 8, 2014 |
| Priority date | — |
| Expiry date | May 31, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
LED dies are suspended in an ink and printed on a first support substrate to form a light emitting layer having a light emitting surface emitting primary light, such as blue light. A mixture of a transparent binder, phosphor powder, and transparent glass beads is formed as an ink and printed over the light emitting surface. The mixture forms a wavelength conversion layer when cured. The beads are preferably sized so that the tops of the beads protrude completely through the conversion layer. Some of the primary light passes through the beads with virtually no attenuation or backscattering, and some of the primary light is converted by the phosphor to secondary light. The combination of the secondary light and the primary light passing though the beads may form white light. The overall color is highly controllable by controlling the percentage weight of the beads.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.