1. The problem statement, all variables and given/known data Hi guys, I have this exercise and I m confused. Incident (white light) light ray is perpendicular to glass surface , glass plate is 0,4microm thick. Which wavelengths in reflected ray becomes more intense? 2. Relevant equations 3. The attempt at a solution So i know that light is refracted on the surface of 2 different mediums, different wavelengths are refracted in different angles. But i do not know nothing about wavelength and/or intensity dependence from reflection. And its seems weird that intensity of some wavelengths increases after reflection. Could someone,please, help? Maybe some tips about which physical phenomenon I should study?