The AA-M provides two simultaneous measurement points: one at the focal plane of the microscope and the other being the point where the optical head of the device is placed, i.e. somewhere before the microscope input. The comparison of the pulse duration value obtained in these two measurements determines the pulse broadening introduced due the dispersion of the microscope's optical elements. In most cases of application of ultra-short pulses in microscopy it is essential to characterize the temporal and spatial profile of the beam in the focal spot of the microscope. These measurements are vital for any experiment as the shorter is the pulse the higher is the efficiency of the nonlinear imaging process (2-photon excitation) and less excitation energy is needed for successful experiment. Such beam characterization is also necessary when determining exposition of the sample. It ensures image optimization and correct intensity level estimation, as incorrect values may even lead to sample damage.
