- #1
dekoi
This is not a textbook question. It is strictly some concepts which I am confused about.
Suppose we have thin film situation.
|||||||||||||||||||AIR|||||||||||||||||||
-----------------------------------------
|||||||||||||||||||FILM|||||||||||||||||
-----------------------------------------
|||||||||||||||||||AIR|||||||||||||||||||
The ray enters the air from the top. Part of it will be reflected from the surface of the film (it has a higher index of refraction). The ray will reflect 180 degrees and thus be 180 degrees out of phase, assuming that the incident ray was normal to surface.
Part of it will also pass through the air/film barrier. According to my professor, the ray will reflect of the film/air barrier, and then be 0 degrees out of phase. This is beyond me! How come the ray reflects of the boundary between film and air? Should it not pass through it without reflection? Also, why would the phase be 0?
In another situation:
|||||||||||||||||||AIR|||||||||||||||||||
-----------------------------------------
|||||||||||||||||||FILM|||||||||||||||||
-----------------------------------------
||||||||||DIAMOND (highest n)|||||||||||
The second reflected ray is said to be 180 degrees out of phase. Once again, why?!
Suppose we have thin film situation.
|||||||||||||||||||AIR|||||||||||||||||||
-----------------------------------------
|||||||||||||||||||FILM|||||||||||||||||
-----------------------------------------
|||||||||||||||||||AIR|||||||||||||||||||
The ray enters the air from the top. Part of it will be reflected from the surface of the film (it has a higher index of refraction). The ray will reflect 180 degrees and thus be 180 degrees out of phase, assuming that the incident ray was normal to surface.
Part of it will also pass through the air/film barrier. According to my professor, the ray will reflect of the film/air barrier, and then be 0 degrees out of phase. This is beyond me! How come the ray reflects of the boundary between film and air? Should it not pass through it without reflection? Also, why would the phase be 0?
In another situation:
|||||||||||||||||||AIR|||||||||||||||||||
-----------------------------------------
|||||||||||||||||||FILM|||||||||||||||||
-----------------------------------------
||||||||||DIAMOND (highest n)|||||||||||
The second reflected ray is said to be 180 degrees out of phase. Once again, why?!