"Dictionary-based phase retrieval for space-time super resolution using lens-free on-chip holographic video"
Zihao Wang, Qiqin Dai, Donghun Ryu, Kuan He, Roarke Horstmeyer, Aggelos Katsaggelos, Oliver S Cossairt
OSA Imaging and Applied Congress, Computational Optical Sensing and Imaging (COSI), June 2017
"4D Tracking of Biological Samples using Lens-free On-chip In-line Holography"
Zihao Wang, Donghun Ryu, Kuan He, Oliver Cossairt, Aggelos K Katsaggelos
OSA Digital Holography and Three-Dimensional Imaging, May 2017
Setup and phase retrieval
The left panel of this image presents our lens-free on-chip imaging setup. On the right, 5 types of protozoa along with the phase retrieval results are presented.
Phase retrieval algorithm
Our "shrink-wrap" phase retrieval algorithm can iteratively recover phase information by gradually estimating the "support" (shape) of the object.
Training a bilevel holographic dictionary
By training a bilevel holographic dictionary, we are capable of recovering high resolution holograms from subsampled holograms. Results show that our subsampled holograms allow imaging at an enhanced frame rate.
Digital refocusing from a holographic snapshot of Paramecium.
By applying the aforementioned phase retrieval method, we are capable of recovering the phase information from the hologram captures.