Phosphor particle with antireflection coating
US5910333A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 1998 |
| Grant date | Jun 8, 1999 |
| Priority date | — |
| Expiry date | Jun 4, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K11/025
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Improved luminous efficiency in plasma displays has been achieved by coating phosphor particles with a dielectric layer having a refractive index, for the ultraviolet light emitted by the plasma, that is intermediate between that of the phosphor and vacuum. When deposited in a thickness range between 0.5 and 5 microns, the layer causes the particle's reflectivity to be reduced because of reduced reflection at the vacuum-coating interface as well as internal reflection at the coating-vacuum interface. For coating thicknesses in the range of 0.1 to 0.5 microns, reflectivity is reduced because of interference between rays reflected at the vacuum-coating interface and the coating-phosphor interface. Several methods for forming these antireflection coatings are described. These include CVD, PVD, and suspension in molten dielectric followed by decanting onto either sticky or non-stick surfaces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.