Diffractive optical elements can be realized as ultra-thin plates that offer significantly reduced footprint and weight compared to refractive elements. However, such elements introduce severe chromatic aberrations and are not variable, unless used in combination with other elements in a larger, reconfigurable optical system. We introduce numerically optimized encoded phase masks in which different optical parameters such as focus or zoom can be accessed through changes in the mechanical alignment of a ultra-thin stack of two or more masks. Our encoded diffractive designs are combined with a new computational approach for self-calibrating imaging (blind deconvolution) that can restore high-quality images several orders of magnitude faster than the state of the art without pre-calibration of the optical system. This co-design of optics and computation enables tunable, full-spectrum imaging using thin diffractive optics.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This work was in part supported by King Abdullah University of Science and Technology (KAUST) baseline funding and the KAUST Advanced Nanofabrication Imaging and Characterization Core Lab. We thank Stefan Bernet for sharing reference designs and prototypes for their system16,17. We also thank Gordon Wetzstein, Robin Swanson, and Shuochen Su for helpful discussions.