SUMMARY
In this study, it has been investigated the effect of Gamma radiation on some optical characteristics of polymetheylacrelate (PMMA) polymer film specimens blended with 9% of phenolphthalein (phph), using casting technology and at room temperature conditions. The thickness of the prepared specimens were (20±2) µm. The absorbance and transmission spectrum have been recorded in addition to their coefficients at range (299-1100) nm. The study has been reported absorbance and transmittance properties of the prepared samples and their coefficients, in addition to the optical gap energy for allowed and forbidden electronic transition. The study concluded that both absorbance and extinction coefficients are increasing proportionally with time of irradiation. While increasing time of exposure of gamma ray on the film layer of the prepared samples resulted in reduction of the optical gap energy property for allowed and forbidden electronic transition value.