In case of thin film of non-uniform thickness, when illuminated with white light, the film appears colored. This is due to change of what factor? (a) Conditions for path difference at different points of film
(b) Change in optical path difference at different points of film
(c) Thickness of film is different at different points of film
(d) All of above
(b) Change in optical path difference at different points of film
(c) Thickness of film is different at different points of film
(d) All of above