I am getting interference fringes in transmittance spectra of CdS thin films. Could anyone please show me their effect on the quality or uniformity of the films ?
You need to look up the basic theory on thin film interference (undergraduate physics) - the fringes depend on the optical thickness (nd) but their finesse will depend on uniformity etc.
Non-uniformity or roughness of the film is scale dependent.
If the films are non-uniform over a large scale, then that cannot be detected or will not affect your transmission curve.
But if the films are non-uniform over a smaller scale, you will have more scattering and less transparency. This will be shown as noise riding on top of your transmission curve.
V.N. Ravi is correct. Just to qualify, nonuniformity (in thickness or refractive index) of the order of a few wavelengths will result in Mie scattering, loss of definition of the fringes (finesse of a cavity) and is usually manifest as a broad background to your spectra.