Fig. 4

Control object used to reconstruct an unknown sample. a The system’s impulse response is measured from a series of known microspheres. When the known shape of the structure is deconvolved from the measured data, the difference contains the system point spread function (PSF). We combined the PSF measurement with the reconstruction step to avoid using two regularizers and recovered the reconstructed volume from subsequent measurements (see Eq. (4)). b Epi-GLIM image of a HeLa cell and 3 μm beads before the tomographic reconstruction (×40/0.75). c Same field of view after the 3D reconstruction showing the cell and bead with the expected spherical morphology. XZ slices are cut along the yellow dash line