Fig. 5: ∅CAO restores optimal resolution in 3D structured illumination microscopy (SIM).

a Selected regions of the frequency distribution used to measure modulation amplitudes are shown at the top displayed with a gamma value of 0.4. A plot of image quality metrics derived from these measurements is shown below. The pseudo wide-field microscopy (WFM) method evaluates intensity variance, whereas the SIM method uses modulation amplitude. b Original and ∅CAO-corrected reconstructed images of yellow-green 100-nm beads using Seidel aberration correction. Middle panel show side views as maximum intensity projections along the Y-axis; bottom panel show corresponding frequency distributions at zero frequency along the Y-axis, displayed with a gamma value of 0.4. c Box plots showing full width at half maximum (FWHM) (µm) of 100-nm beads (n = 13) before and after correction. d Intensity profiles along the Y- and Z-axes of the beads indicated by the circle in (b). e Regions used for aberration measurement in a fixed HeLa cell stained for microtubules. Maximum intensity projections along the Z- and Y-axes are shown. f 3D-SIM reconstruction of microtubules in a HeLa cell before and after ∅CAO correction using Seidel aberrations. Boundaries between subregions (numbered 0, 2, and 3) to apply correction are indicated by gray lines in the uncorrected image. Corresponding wavefronts used for correction are shown in the corrected image. g Maximum intensity projection along the Z- and Y-axes of DAPI-stained chromosomes in meiotic prophase of fixed C. elegans embryos. Subregions used for aberration measurement are indicated by blue boxes. h Multicolor optical section of 3D-SIM with or without ∅CAO correction using Seidel aberrations. White lines in the merged image indicate boundaries between subregions (numbered 0, 1, and 2) corrected using distinct wavefronts. Corresponding wavefronts are shown in the corrected images. Pseudo-color was applied to the merged image. i Reconstructed 3D-SIM images in unoptimized blue (435 nm) and red (609 nm) channels. Representative images from three subregions (indicated in h) are shown. Wavefronts used for correction are displayed on the right. j Line profiles along the lateral or axial directions of the blue line in the merged images in h, comparing images with or without ∅CAO correction.