Abstract

Liquid crystal light valves¹ show a very rich spatiotemporal dynamics even when illuminated by a relatively low intensity laser light. This has transformed them into work horses for the study of pattern formation in nonlinear optics. An example of such applications in an experiment recently performed at the Institute of Optics in Florence.² The main differences between this experiment and others that have studied similar systems³ are that the fibre bundle (see Fig. 1) induces a π rotation in the feedback field and that it is possible to insert an attenuating filter in front of half of the light valve so as to break the rotational symmetry of this system. The dynamics observed is indeed extremely rich:² by changing the various experimental parameters, for example the light intensity or the absorption coefficient of the attenuating filter, it is possible to observe stationary or dynamical patterns of rolls and/or hexagons.

© 1994 IEEE