Optimization of single-beam multiple-intensity reconstruction technique: Select an appropriate diffraction distance

The multi-distance phase retrieval technique is widely used in phase imaging due to its high accuracy, simple implementation, and strong robustness. However, the artificial selection of the diffraction distance for capturing images has been a limitation. This limitation has sparked the desire to improve the accuracy of multi-distance phase retrieval by either capturing more images at different diffraction distances or iterating more times in the algorithm. Unfortunately, these approaches significantly reduce the efficiency of the technique. In this study, we implemented detailed simulations of the single-beam multiple-intensity reconstruction (SBMIR) technique to investigate the relationship between the diffraction distance and phase retrieval accuracy. We conducted experiments using an USAF-1951 sample generated by LCOS-SLM, a circular steps sample, and a biological sample. The results verified that SBMIR achieves higher phase retrieval accuracy and faster efficiency at an optimal diffraction distance. This research provides valuable support for selecting the appropriate diffraction distance in SBMIR, thereby enhancing its accuracy and efficiency.