21.4. Polarization http://www.ck12.org
2 d=mλ,m= 0 , 1 , 2 ,...
6b. Destructive interference for thin films when there is no effective phase change is
2 d=
(
m+^12)
λ,m= 0 , 1 , 2 ,...7a. When a beam of light is reflected from a medium with a greater index of refraction than the medium in which
it travels, it undergoes a phase change of 180◦upon reflection. The condition for a constructive interference when a
phase change of 180◦occurs is given by the equation
2 d=
(
m+^12)
λ,m= 0 , 1 , 2 ,...7b. The condition for a destructive interference when a phase change of 180◦occurs is given by the equation
2 d=mλ,m= 0 , 1 , 2 ,...
- Polarization is a property associated with transverse waves –most typically, electromagnetic waves. Light that is
polarized has electric field vibrations in only one plane. A “polarizer” filters out all of the vibrations in a transverse
wave that are not in a particular plane. A polarizer that permits vertical vibrations to pass has vertical axis of
polarization. A polarizer that permits horizontal vibrations to pass has horizontal axis of polarization. Light can be
polarized by transmission or reflection.