Photoreflectance spectra from superlattices and quantum wells exhibit a
variety of pecularities which may be used in order to derive electronic
structure data, provided experimental lines shapes are properly understood.
This problem is addressed in the present paper. The electric field effect on
optical constants is expressed in terms of the Franz-Keldysh as well as Stark
effect of mini- and subbands. Theoretical line shapes are given and compared