We describe a new dynamic Light scattering technique for measuring dif
fusion in sheared suspensions. It involves a scattering geometry with
two crossing laser beams. A detailed analysis of the correlation funct
ion of scattered Light is given. The viability of our method is demons
trated in an experiment where the effect of Taylor diffusion on the sc
attered light correlation function is measured. (C) 1998 American Inst
itute of Physics.