Fluorescent dye added to epoxy of light emitting diode lens
US5847507A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 1997 |
| Grant date | Dec 8, 1998 |
| Priority date | — |
| Expiry date | Jul 14, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/853
Abstract
A process and apparatus is described to produce efficient light emission over a broad portion of the visible spectrum. A lens containing a fluorescent dye is over molded to a short wavelength light emitter (e.g., a blue LED or laser diode) placed within a reflector cup. The fluorescent dye absorbs at least a portion of the light emitted by the diode and re-emits light of a second, longer wavelength. Concentration of the dye within the lens can be varied to control the extent of a region within the lens where most of the light is re-emitted so the remaining portion of the lens can focus the light. One can readily and consistently tailor the color of the light emitted from the lens through selection of the number and types of fluorescent dyes added to the lens, and through their relative concentrations. Inventory is reduced and there are no additional steps required when building varied color LEDs. One simply controls the color of the LED being made by selecting from one of several possible fluorescent dye-containing lens epoxies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.