Table 1 Radial and axial Point Spread Functions of the system can be directly estimated, in single- and two-photon excitation regimes, measuring the Full Width at Half Maximum (FWHM) of the radial and axial profiles shown in Fig. 2.

From: 4D (x-y-z-t) imaging of thick biological samples by means of Two-Photon inverted Selective Plane Illumination Microscopy (2PE-iSPIM)

Excitation regime Wavelength nm Objective Radial (FWHM) μm Axial (FWHM) μm
Single Photon excitation (1PE) 405 10X, 0.3 NA 1.78 ± 0.05 2.6 ± 0.1
Two Photon excitation (2PE) 740 10X, 0.3 NA 1.82 ± 0.04 2.5 ± 0.1
  1. The average value of the FWHM of the radial profile in single photon excitation, statistically calculated over 20 measurements, was found to be 1.78 ± 0.05 μm while in Two-Photon Excitation was found to be 1.82 ± 0.04 μm. Similarly, the axial profiles of the intensity distribution for single and two-photon excitation have been calculated, showing average values of FWHM of 2.6 ± 0.1 and 2.5 ± 0.1 μm, respectively.