Multi-modality non-linear microscopy

Summary form only given. Two-photon fluorescence microscopy (TPFM) meets wide applications in biology with high axial resolution without using a confocal aperture. In TPFM, strong fluorescence emission is restricted to the vicinity of the focal point with the advantage of minimum out-of-focus absorption, photo-bleaching and damage. The use of near infrared (NIR, generally around 800 nm) leads to deeper penetration in most biological specimens than conventional light sources, providing an opportunity for tissue imaging.