In 4Pi fluorescence microscopy the point-spread function is composed of a strong central lobe accompanied by interference sidelobes that produce artifacts in the image. We propose to combine two-color two-photon fluorescence microscopy and 4Pi fluorescence microscopy to overcome this sidelobe problem. Simulation results show that a single sharp fluorescence spot can be produced by use of two excitation wavelengths of 400 and 800 nm and detected at 350-nm emission wavelength.
© 2004 Optical Society of America
Jianfang Chen and Katsumi Midorikawa, "Two-color two-photon 4Pi fluorescence microscopy," Opt. Lett. 29, 1354-1356 (2004)