Figure 1.

Molecules in the excited state as a function of repetition rate (RR). The number of molecules in the excited state at the instant that an excitation pulse arrives is calculated using a) Equation (2) for five pulses (n=5), and b) Equations (1) and (3) for infinite pulses. The blue lines represents calculations for a fluorophore with a 100 ns lifetime, the red lines for 10 ns, and the green lines for 4 ns, the last of which being the approximate lifetime for commonly-used organic dyes. Increasing the RR increases the excited state population at a rate which increases fro longer-lived dyes. Note that the vertical axes are logarithmic. The dotted, vertical line is drawn at RR = 80 MHz, a commonly avalable RR for pulsed diode lasers.