Probability distributions of the peak output power from planar microca
vity dye lasers with pulsed excitation have been studied experimentall
y. Two microcavities were used, one operating possibly with a single m
ode and the other possibly with a number of modes. These expectations
are based on the relative magnitude of the mode radius and the pump be
am radius. In the former cavity an exponential-like distribution was o
bserved below threshold, which indicates single-mode operation. In the
latter cavity a single-peaked distribution appeared even below thresh
old indicating multiple-mode operation. These results are, respectivel
y, in qualitative agreement with theoretical distributions for steady
state. That the observed pulse width is large enough to apply steady s
tate distribution equation is shown by calculating the characteristic
transient time for the intensity distribution. (C) 1996 American Insti
tute of Physics.