Fig. 5. Comparing reconstruction algorithms for COIL applications.
Reconstructions of various objects using experimental or simulated data and either an established ghost imaging algorithm (Eq. 5 in [Sun18]) (middle row) or SARA–COIL (bottom row). a 125 × 125 pixel reconstructions of an off-centre cross for Np = 121 using experimental data. b 377 × 377 pixel reconstructions of an offset cross for Np = 1089 using experimental data. c, d 511 × 511 pixel reconstructions of the A549 cells (c) and the USAF target (d) for Np = 2000 using simulated patterns and overlap data. Note that regions with no available information are treated differently by the two algorithms. As seen in the corners of all images, the ghost imaging algorithm assigns a mid-scale value, whereas SARA–COIL assigns a value of 0. In images reconstructed from experimental data, 1 represents the regions of highest transmission, and in those based on simulated data 1 represents regions of highest intensity. The field of view of all reconstructions using experimental data is 0.9 mm × 0.9 mm in the object plane. We thank Eckhardt Optics for allowing us to use their image of the USAF 1951 resolution test chart presented at the top of column d.