Abstract
The 
phosphor has been investigated for its application to vacuum fluorescent displays (VFDs) utilizing low‐voltage cathodoluminescence. It is expected that this oxide phosphor does not cause damage to filaments in VFD's, while it is a serious problem for conventional sulfide phosphors. This phosphor shows blue luminescence with a spectral peak at 470 nm and a chromaticity at 
and 
. A luminous efficiency of 0.7 lm/W has been obtained, when the VFD with this phosphor is operated at 30 V dc. The results of high‐temperature operating life test have proven the excellent stability of VFDs utilizing this phosphor.