The visibility V of the fringes observed in a Michelson interferometer is defined asWhere Imax and Imin are the intensities at the maxima and minima of the fringe pattern. In observations of the sodium D-lines, V varies from a maximum of 1.00 to a minimum of 0.33 over a range of approximately 500 fringes. Explain these observations and deduce values for the fractional wavelength difference between the sodium D-lines and for their relative intensities.

Transcribed Image Text:

Imin Imax Imax + Imin