Luminescent coating for low-pressure mercury vapour discharge lamp
US3937998A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 25, 1974 |
| Grant date | Feb 10, 1976 |
| Priority date | — |
| Expiry date | Sep 25, 1994 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K11/7787
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A low-pressure mercury vapour discharge lamp provided with a luminescent coating comprising three luminescent materials each emitting in a narrow spectral range. The first material has an emission band with a maximum between 430 and 490 nm; the second material has its emission in the range 520-565 nm; the third material emits in the range 590-630 nm. The second material is defined by one of the formulas: PA1 A. Ce.sub.1-x-y La.sub.x Tb.sub.y MgAl.sub.11 O.sub.19 PA1 b. (Ce.sub.1-x-y La.sub.x Tb.sub.y).sub.2 O.sub.3.nAl.sub.2 O.sub.3 The first material is preferably chosen from PA1 C. A.sub.1-p Eu.sub.p Mg.sub.2-q Mn.sub.q Al.sub.16 O.sub.27 PA1 d. B.sub.5.5-x Eu.sub.x Mg.sub.6-y Mn.sub.y Al.sub.55 O.sub.94 (a and B are barium and/or strontium).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.