Lamp phosphors and color gamut in positive-column gas-discharge cells for TV displays

Phosphors suitable for a full-color TV display in recently reported new high-luminance (360-fL green) high-efficiency (3.4-lm/W) gas-discharge cells have been determined: blue Sr
5
Cl(PO
4
)
3
Eu
⁺²
, green Zn
2
SiO
4
:Mn
⁺²
, and red Y
2
O
3
Eu
⁺³
. A decrease in color gamut with increasing current density has been measured and related to gas-discharge effects rather than phosphor saturation, using experimental results and a simplified model calculation. Aging of the green phosphor was measured and its causes are discussed.