Michelson interferometer

This applet lets you study the Michelson interferometer and see the evolution of light rings as the parameters of the system are changed. The case of a point source, which corresponds to the Twyman interferometer, is also analyzed. The Michelson interferometer consists of an extended source located at the focal plane of a lens (so the emerging rays are parallel), a semireflecting plate that divides the beam into two, and two Mirrors. The beams, after reflection at the mirrors, are re-combined at the plate Exit and interfere. The interferences are observed at the focal plane of a collimator lens. As the vertical beam traverses the plate three times while the horizontal beam passes through it only once, a compensating plate of the same material and thickness as the semireflecting plate is added in the horizontal arm.