Spectroscopic Properties Study of Coumarine -47 Dye doped Poly Methyl Methacrylate


A thin film of Coumarine -47 has been prepared in a chloroform solvent mixed with the same ratio of Poly Methyl Meth Acrylate ( PMMA ) at different concentrations (1x10-4 , 5x10-4 and 1x10-3 ) M . This film has been prepared by using thermal oven with temperature about (333 K) and pressure at 10-2 torr for 1 hour. The prepared thin film thickness measured using Michelson interferometer is around 0.2mm.The quantum efficiency decreased as follows (80%, 74% and 59% ) respectively. The radiative life time and fluorescent life time has been investigated as a function of dye concentration and it can be shown that they both decreased (8.57, 3.35 and 2.5) ns and (6.85, 1.97 and 1.85) ns respectively. It has been determined that the resulting overlap between the absorption spectrum and fluorescence spectrum for thin film is less than that shown for the solution, therefore stock shift will be more . From the morphological studying of the thin film it has been shown that with the increasing the concentration the defects and inhomogenity of the film increase.