Light emitting diode device having multilayer filter for improving color characteristic of light
US11417810B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2020 |
| Grant date | Aug 16, 2022 |
| Priority date | — |
| Expiry date | Jun 30, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/841
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An LED device includes: a first semiconductor layer of a first type; a second semiconductor layer of a second type; a light emitting layer formed between the first semiconductor layer and the second semiconductor layer and configured to emit light; and a filter formed on the second semiconductor layer and configured to transmit light in the second wavelength band within the first wavelength band. The filter includes a defect layer, first refractive layers, and second refractive layers having a refractive index greater than a refractive index of the first refractive layers, the first refractive layers and the second refractive layers are formed alternately on one side and other side of the defect layer. A thickness of the defect layer is determined based on a center wavelength of the first wavelength band, a peak wavelength of the second wavelength band and a refractive index of the defect layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.