Dopping Effect On Optical Constants of Polymethylmethacrylate (PMMA)

Abstract

The optical constants (refractive index (n) , extinction coefficient (k) , realand imaginary parts of dielectric constant(ε1&ε2)) of polymethyl methacrylate(PMMA) doped with methylene blue (mb) and methyl red (mr) withthickness in the range (0.1-0.2) mm were measured in the wavelength range(200-900) nm. Refractive index (n) and extinction coefficient (k) showedirregular changes with increasing (mb) dopant concentrations, while (n) and(k) of PMMA doped with (mr) declared a systematic increase with increasingdopant concentrations. The data showed that (n) values of PMMA doped with(mr) are lower than the values of samples doped with (mb) which isatteributed to the progressive increase of absorbance in the wavelength range(400-550) nm with increasing (mr) concentration .