Igor Kudzej Vihorlat Observatory, Humenne, Slovakia
This paper discusses the fine effects in photoelectric light curves
of eclipsing binary stars, and shows the classification of fine effects and their
deformational influence on a light curve if they are present in the binary system. More
detailed analysis is given for one of them--the effect of refraction electromagnetic
radiation in the atmospheres of close binary stars. This effect deforms the light curve
during the total eclipse. On the light curve it is manifested by the small hump in the
constant part of the minimum. This effect is registered in seventeen systems.