| abstract |
This disclosure features fluorescent lamps that include a phosphor layer including at least one phosphor, which in the past has not been commercially usable in lamps or in some cases suffers from performance problems such as poor brightness. These problems of the phosphors were caused, for example, by mercury ion bombardment or exposure to 185 nm radiation from the discharge. These problems are expected to be avoided by coating particles of one or more of the phosphors, such as using atomic layer deposition in which the coating is not more than 500 nm in thickness. Examples of phosphors that can be coated are yttrium vanadate activated with europium or yttrium vanadate phosphate activated with europium. The coating can be selected from the group consisting of alumina, yttria, lanthanum oxide, magnesium aluminate spinel, magnesium oxide and combinations thereof. |