Transparent thin films of polyepoxypropylcarbazole polymer were produced using spin-coating technique. Optical materials constants such as refractive index of thin films and thickness were determined by optical spectroscopy. It was shown the possibility of variation of film thickness by polymer concentration in solution. It was shown that film thickness dependence on the concentration of solution is linear. Therefore this linear dependence can be used to predict the film thickness of spin-coated polymers if the solvent is known. The thickness can be varied from 170 nm up to 940 nm for the solution with concentration from 2.5% up to 12.5%. To confirm the validity of our method, we also carried out the interferometric thickness measurements and analysis with a thin film of polyepoxypropylcarbazole. The difference of obtained results of two methods averaged not more than 5%.The measured film thickness by transmission spectra of the polymer film was found to be well correlated to the results of interferometric thickness measurement. The refractive index of the polyepoxypropylcarbazole was 1.62, which was well above the refractive index of 1.49 for polymethylmethacrylate. It was found that the inclusion of even a small amount of a photosensitizer, such as CHI 3 , was effective in producing of high refractive index material with refractive index 1.64.

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The transmission spectra of bulk and thin films of (As 2 S 1.5 Se 1.5 ) 1-x :Sn x in the visible and near infrared (IR) regions were investigated. Doping of As 2 S 1.5 Se 1.5 chalcogenide glass with tin impurities essentially reduce the absorption bands of S-H (Se-H) and H 2 O located at ν = 5190 cm -1 and ν = 3617 cm -1 , respectively. The amorphous As 2 Se 3 :Sn x and (As 2 S 1.5 Se 1.5 ) 1-x :Sn x thin films exhibit photoinduced effects under the light irradiation with photon energy above the optical band gap (hν≥E g ), that make its perspective materials for registration of optical and holographic information. The modification of optical parameters (optical band gap E g , absorption coefficient α, refractive index n) under light irradiation and heat treatment of the amorphous thin films with different amount of Sn was studied. The shift of the absorption edge after light exposure to lower energy region was observed, i.e. the effect of photodarkening take place. The dispersions curves n=f(λ) show a modification of the refractive index n under light exposure. For the glass composition (As 2 S 1.5 Se 1.5 ) 0.96 :Sn 0.04 the change of the optical band gap Eg opt under light exposure was determined from 1.92±0.02 eV to 1.86±0.02 eV. The similar calculations of the optical constants were done for the amorphous films of glass compositions x=0.03 and x=0.05. The relaxation of photodarkening in amorphous As 2 Se 3 :Sn x and (As 2 S 1.5 Se 1.5 ) 1-x :Sn x thin films, which is described by the stretch exponential function T(t)/T(0) = A 0 +Aexp[-(t-t 0 )/τ] (1-α) also was investigated. The experimental results are interpreted in framework of the model of molecular structure of chalcogenide glasses doped with tin impurities.