The spectra of zinc silicates with varying concentrations of manganese were measured at several temperatures. It was found that these emission spectra could be separated into bands conforming to Gauss error curves and that the location of these bands is almost unaffected by temperature and composition changes. It is shown that the width of these bands increases linearly with temperature and that the bands become wider as the activator concentration departs from the optimum. The dielectric losses of these phosphors were also measured as a function of the temperature and the very close connection between luminescence and dielectric losses first reported by Szigeti and Nagy for a zinc silicate sample was found valid for any zinc silicate. The electrical and luminescent constants all show maxima for the best fluorescing substances. These data make it very doubtful that activation is confined to divalent manganese. Consequently, a close analogy between the emission spectra of these silicates and the absorption spectra of permanganate and manganate compounds is worth studying.
[1]
K. H. Butler.
Emission Spectra of Silicate Phosphors with Manganese Activation
,
1948
.
[2]
E. Makai,et al.
A Spectroscopic Evidence for Activation of Fluorescence by High Valency Manganese Ions
,
1947
.
[3]
G. Szigeti,et al.
Dielectric Losses and Fluorescence of Zinc Silicate
,
1947,
Nature.
[4]
M. P. Lord,et al.
The short-period time-variation of the luminescence of a zinc sulphide phosphor under ultra-violet excitation
,
1947
.
[5]
S. T. Henderson.
Band spectra of cathodo-luminescence
,
1939
.
[6]
G. R. Fonda.
Characteristics of Silicate Phosphors.
,
1939
.
[7]
J. Randall.
The Fluorescence of Compounds Containing Manganese
,
1939
.