We present a quantitative experimental comparison of fiber-based, sing
le- and few-mode dynamic light scattering with the classical pinhole-d
etection optics. The recently presented theory of mode-selective dynam
ic light scattering [Appl. Opt. 32, 2860 (1993)] predicts a collection
efficiency and a signal-to-baseline ratio superior to that of a class
ical pinhole setup. These predictions are confirmed by our experiments
. Using single-mode optical fibers with different cutoff wavelengths a
nd commercially available mechanical components, we have constructed a
mode-selective detection optics in a simple and compact dynamic light
-scattering spectrometer that permits an optimal compromise between si
gnal intensity and dynamical resolution.