A novel neural-network architecture that combines image data reduction
with focus of attention to achieve reduced training cost, improved no
ise tolerance, and better generalization performance than comparable c
onventional networks for image-recognition tasks is presented. The dua
l-scale architecture is amenable to optical implementation, and an exa
mple optical system is demonstrated. For one example problem, the best
-case improvements of the dual-scale network over its conventional cou
nterpart were found through simulation to he a factor of 6.7 in traini
ng cost, 67.3% in noise tolerance, and 61.6% in generalization to dist
ortions. The dual-scale network is also applied to one instance of a h
uman face recognition problem.