International Journal of Academic and Applied Research (IJAAR)   Year: 2021 | Volume: 5 | Issue: 12 | Page No.: 62-67 Optical Properties of Different Gum Arabic Thin Film Nada .Abbas. Ahmad, Sohad. Saad. Elwakeel , Abdelmoneim. M. Awadelgied, Al desogi. Omer Hamed, Abdalsakhi. S. Mohammed Abstract: Twelve samples of Gum Arabic thin film were synthesized by mechanical method. UV- spectrophotometer was used to determine some optical properties. The maximal absorbance value equal (0.995 a.u) at wavelengths (257 and 295) nm for Hashaba, but for Neem equal (0.876 a.u) at (230 and 287) nm and for Talha equal (1.0029 a.u) at (230 and 287) nm and the value of absorbance increase by thickness of each sample increase. The absorption coefficient (?) of the three groups samples of Gum Arabic (Hashaba, Neem and Talha) maximal value equal ( 1.6x108) for all types at different wavelengths (258)nm for Hashaba, (229.7) nm for Neem and 230.46nm for Talha , this means that the transition must corresponding to a indirect electronic transition.The value of the optical energy gap (Eg) of all samples were increased from (3.925 eV) to (4.049 eV),and this due to decreased in thickness of samples.