Phosphor materials find wide applications ranging from fluorescent
display to luminescence immunoassay. These materials essentially convert
one type of energy in to visible radiation and hence, phosphor materials are
called optical transducer. They are generally crystalline in nature. Phosphors
with high quantum efficiency, effective excitation and absorption, colour
parity, longer lifetime and lower cost, as well as better morphology are
required. Surface properties have important function for phosphors.
Spherical phosphors are optimum morphology in application. The spherical
particles are easy to be packed density so that the screen and display can
obtain high definition. In addition the dense packed small particles can
prevent phosphors from aging.