Next Generation of Nonlinear Laser Microscopy Based on High Energy Fs-Pulses: Widefield Mode Up to 2.2 Microns

State of the art nonlinear microscopes are based on non-regeneratively amplified fs-laser having a typical repetition rate of $v\approx 80$ MHz and a maximum energy per pulse of $\mathrm{E}_{\mathrm{p}}\approx 100\ \text{nJ}$ . In this work the use of a different type of laser technology, the one of regeneratively amplified laser, is explored. These systems can deliver pulse energies up to $\mathrm{E}_{\mathrm{p}}\approx 1\ \text{mJ}$ with a repetition rate up to $\approx 1$ MHz. This choice was already proven to be beneficial to improve the imaging depth [1] but it brings other unexplored advantages, which are the heart of the recently conceived Tunable hIGh EneRgy (TIGER) microscope [2].