PMID18204458 Highspeed, lowphotodamage nonlinear imaging using passive pulse splitters
 Core idea: take a single pulse and spread it out to $N= 2^k$ pulses using reflections and delay lines.
 Assume two optical processes, signal $S \propto I^{\alpha}$ and photobleaching/damage $D \propto I^{\beta}$ , $\beta \gt \alpha \gt 1$
 Then an $N$ pulse splitter requires $N^{11/\alpha}$ greater average power but reduces the damage by $N^{1\beta/\alpha}.$
 At constant signal, the same $N$ pulse splitter requires $\sqrt{N}$ more power, consistent with two photon excitation (proportional to the square of the intensity: N pulses of $\sqrt{N}/N$ intensity, 1/N per pulse fluorescence, $\Sigma \rightarrow 1$ overall fluorescence.)
 This allows for shorter dwell times, higher power at the sample, lower damage, slower photobleaching, and better SNR for fluorescently labeled slices.

 Examine the list of references too, e.g. "Multiphoton multifocal microscopy exploiting a diffractive optical element" (2003)
