text: Figure 4 shows an experimental realization of the
  Gaspard–Rice system using a laser instead of a point particle.
  As anyone who's actually tried this knows, this is not a very effective
  method of testing the system—the laser beam gets scattered in every
  direction.  As shown by Sweet, Ott and Yorke,
  a more effective method is to direct coloured light through the gaps 
  between the discs (or in this case, tape coloured strips of paper across pairs of cylinders)
  and view the reflections through an open gap.
  The result is a complex pattern of stripes of alternating colour, as
  shown below, seen more clearly in the simulated version below that.
  Figures 5 and 6 show the basins of attraction for each
  impact parameter, b, that is, for a given value of b, through which gap
  does the particle exit?  The basin boundaries form a Cantor set and
  represent members of the stable manifold: trajectories that, once started, never
  exit the system.