The spectral changes arising due to interference between two partially
correlated beams are investigated experimentally in a Mach-Zehnder in
terferometer. Two different schemes are used to produce two partially
correlated beams. Experimental results obtained from these schemes are
compared with the theory. It is shown that the spectral changes in th
e form of modulations in the superposed spectrum are dependent on the
optical path difference of the two beams in the interferometer and can
be utilized for determining linear displacements of a few microns.