In this article we discuss two aspects of nonlinear optical patterns. The f
irst concerns the possibility of a future application to information proces
sing, based on the realization of arrays of spatial soliton pixels in broad
area semiconductor microcavities. We outline the concepts, the control and
the perspectives. The second aspect concerns the quantum features of nonli
near optical patterns. We discuss the concept of quantum image in the frame
work of parametric down-conversion processes. Numerical simulations show th
e transition from a quantum image to a classical image across the threshold
region of a degenerate optical parametric oscillator. An experiment with l
ithium triborate shows strikingly similar results in both the near and the
far field, displaying qualitatively the classical features of quantum image
s. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.