Ptycho-cam: a ptychographic phase imaging add-on for optical microscopy

Near field ptychography uses diffraction data collected at large Fresnel numbers, together with iterative reconstruction algorithms, to realize quantitative phase imaging of transmissive samples. It delivers excellent phase sensitivity with a wide field of view from a simple optical system using a relatively small number of measured diffraction patterns. In this paper, we develop an add-on to a standard optical microscope that implements near-field ptychography. The add-on is self-contained and attaches to the microscope camera port, requiring no modification to the microscope itself. Unlike conventional ptychography, it does not involve sample translation, making it more suitable for delicate samples or samples in liquid.