Theory of Michelson Interferometer Experiment
Monochromatic light beam from a laser source is splitted into two beams. the two beams are reflected back from two mirrors to a screen, where interference pattern is observed. By moving one of the two mirrors or both, the phase difference between the two beams changes and the fringes crossing the field of vision changes in number accordingly.
Michelson Interferometer Principle
In michelson interferometer experiment, The number of fringes crossing the field of vision is counted as one (or both) of the two mirrors is moved or by rotating the glass plate stage through angle . hence the wavelength of laser and the refractive index of the glass plate could be determined.