Polarized wavefront measurement using an electrically tunable focused plenoptic camera

Performing optical imaging of relatively small or weak targets in complicated background, as a primary approach used to explore the nature, is limited in performance by atmosphere-induced optical aberrations. Methods that characterize wavefront aberration have improved our understanding of how wavefront distortions degrade image quality. However, these approaches are unable to show the light-field and polarization information except for the wavefront aberration. The integrated imaging chip or microsystem that can acquire more dimensional information is crucial for researchers to see more clearly into the scene. To address this question, an electrically tunable focused plenoptic camera that is used to visualize objects directly in a snapshot with multi-dimension perception such as wavefront, polarization, and light-field information, is proposed and demonstrated. This prototyped camera, which is composed of a twist nematic liquid-crystal microlens array (TN-LCMLA) and a common CMOS sensor array, can directly sense two orthogonally polarized light-field images via switching the working stated of TN-LCMLA. This prototype records not only intensity and polarization information but also the direction and position of incident beams, so as to indicate that the localized wavefront slope of incident beams can be extracted directly. In this study, the theoretical analysis, reconstruction algorithm and experiment results show that a high performance and functional detection are obtained by this novel configuration. Then, with the proposed algorithm, the prototyped camera has a potential to be used in adaptive imaging application and many other optical systems.