The three pairs of complex refractive indices and the direction of the opti
cal axis for metal insulator thin film composites in which the very small m
etal particles form narrow tilted columns I-which are arranged asymmetrical
ly have been found using a combination of ellipsometry and spectrophotometr
y. Results have been used to theoretically model transmittance which depend
s on the two angles defining incident direction in these films. Insights in
to the unusual optical response of the nano-size silver particles are also
given. (C) 1999 Acta Metallurgica Inc.