In order to improve the afterglow properties testing standardization of the long afterglow materials,the afterglow properties of the long afterglow SrAl_2O_4: Eu~(2+),Dy~(3+) were measured by using ST-86LA brightness meter.

SrAl_2O_4:Eu~(2+),Dy~(3+) system long afterglow materials have been accepted as one of the most important luminescent materials, due to the advantages of its wide excitation spectrum, visible emission range, high luminescent intensity, non-poisonous, non-radioactivity, long afterglow and high stability.

The Sr_2MgSi_2O_7∶Eu~(2+),Dy~(3+) is an excellent blue long afterglow phosphor.

As novel functional materials, long afterglow phosphors are drawing more and more attention in recent years because of a constantly growing market for their applications in traffic signs, emergency signage, watches and clocks, textile printing, among others.

Afterglow property of long afterglow phosphor Sr_2MgSi_2O_7∶Eu~(2+),Dy~(3+) and the influence of Dy~(3+) on its afterglow time;

This dissertation deals nonlinear transmission property for new type of one-dimensional photonic crystals containing composite defects consisting of negative-index material, subwavelength material and Kerr-type nonlinear materials.