Approaching two-photon excitation microscopy from PCM2000 confocal to PRISM image scanning system. (Conference Presentation)

The advent of two-photon excitation (2PE) to produce microscopy images is the most important revolution in fluorescence microscopy. Since the recording of fluorescence by Sheppard within a non linear scanning microscopy scheme in 1978 to the effective application in 1990 by Denk and colleagues at the Webb labs at Cornell, 2PE microscopy changed the way of getting information from 3D biological systems in a way that is more powerful than confocal or super resolved fluorescence microscopy. The big jump, in terms of applications, took place with the advent of pulsed and mode-locked Titanium-Sapphire lasers. From the very first attempt to adapt confocal scanning heads like the ultracompact PCM2000 by Nikon to image scanning microscopy using PRISM by Genoa Instruments, a lot of solutions have been implemented. 2PE super resolved microscopy using an image scanning approach and the coupling with label-free Mueller matrix signature are the tip of an iceberg to be explored.