Resolution in potential three-photon fluorescence scanning microscopy is discussed in terms of the threedimensional optical transfer function. Images of layers and sharp edges are presented for a comparison of the resolution with that in two-photon fluorescence microscopic imaging. For the same fluorescence wavelength the resolution is almost the same in both cases. However, for a given illumination wavelength the resolution for imaging a thick object in the case of three-photon fluorescence imaging can be improved by as much as 40–50% relative to that in two-photon imaging.
© 1996 Optical Society of America
Min Gu, "Resolution in three-photon fluorescence scanning microscopy," Opt. Lett. 21, 988-990 (1996)