Phosphor blend lamps which reduce the proportions of the costlier phosphors
Abstract
Abstract An improved luminescent combination wherein the emissions of distinct luminescent materials are blended to provide a predetermined spectral energy distribution for the combination. When one of the blend constituents is particularly expensive, the requisite amount of this material can be substantially reduced by providing a plurality of luminescent layers with the expensive material being disposed as the layer nearest the source of ultraviolet radiations. This increases the absorption of ultraviolet radiations by this expensive material and its corresponding emission. The desired spectral energy distribution for the combination can be provided with substantially less of the most expensive luminescent material.
Inventors
- 👤 William A Thornton
- 👤 Joseph W Sausville
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-30 | 1975-03-01 | 1975-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-30 | 1979-03-01 | 1979-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-30 | 1983-03-01 | 1983-08-31 | $7700.00 | Window Closed / Lapsed |