A new synthetic cathodoluminophor with long Persistence

Dy

3+

activated SrAl

2

O

4

is presented in this Paper. The CL spectrum consists of three groups of discrete sharp lines which is characteristic of Dy

3+

ion 4f-4f transfer appearing yellow-white in color. The CL brightness is comparable to commercial MgF

2

:Mn

2+

(P33)

or about 60% that of Zn

2

SiO

4

:Mn

2+

As(P39).The SrAl

2

O

4

:Dy

3+

phosphor shows a decay time of more than 200ms to decrease to an intensity of 1/10 of its initial value after the removal of CR excitation of 10kV

1μA/cm

2

and the luminescence decay is nonexponential. Thermoluminescence of CR excitation shows the existence of deep traps which are responsible for the slow decay.Finally the model of luminescence decay in this phosphor is proposed according to experimental results.