Fig. 1. Schematic plot of the experimental setup and the concept of the noniterative diffractive imaging method. (a) A PAM is placed between the object and the camera. The PAM is specially designed such that we can retrieve the correlation function of the incident light by inverse Fourier transform of the measured diffraction pattern. (b) The PAM consists of a reference pinhole at the origin (gray square) and a periodic array of the measurement pinholes with certain offset (white squares). (c) In the inverse Fourier transform of the diffraction pattern, the autocorrelation terms (gray squares) and the two interference terms (red and blue squares) are separated by the offset. Each interference term directly contains the correlation between the fields at the reference pinhole and at the measurement pinholes.
Fig. 2. The experimental setup for generating the GSM beam and for diffractive imaging. BE, beam expander; RGGD, rotating ground-glass disk; GAF, Gaussian amplitude filter; BS, beam splitter; SLM, spatial light modulator; PAM, pinhole array mask; L1, L2, and L3, thin lenses; and CCD, charge-coupled device.
Fig. 3. The unperturbed and the perturbed object transmission function and the experimental results using GSM beam illumination with various degrees of spatial coherence. The phase of (a) the unperturbed and (b) the perturbed objects. The perturbation is at the head of the panda. (c1)–(c3) The amplitude and (d1)–(d3) the phase of the reconstructed product of the object’s transmission and the illumination’s correlation using GSM beam for illumination with various degrees of spatial coherence.
Fig. 4. The experimental results under GSM beam illumination with low degree of spatial coherence (
Fig. 5. The experimental results using LGSM beam illumination: (a) the reconstructed product of the object’s transmission and the illumination’s correlation; (b) the calibration results of the illumination’s correlation using an empty window as object; and (c) the object’s transmission obtained by dividing the results in (a) by the results in (b).