Portable lensfree single-frame imaging sensor using random phase modulation

We report on what we believe to be a novel portable lens-free imaging sensor that enables high-quality complex-valued image recovery for various application scenes. In the prototype, a bare CMOS sensor chip and a binary phase mask are integrated as a coded sensor to capture a single-frame coded intensity image of a sample, and then an iterative filtering coded phase retrieval (IFCPR) is designed to achieve wavefield reconstruction of the sample. In the experiment, we validate the imaging performance of our platform by imaging a stained pathological slide, a microlens array, and a reflective sample. Compared to traditional lens-free single-frame imaging methods, our platform shows high-fidelity and background-enhanced image recovery for different forms of sample types. In addition, the reported platform can be implemented as an embedded module to realize wavefield recovery in a wide-field microscope or imaging through a scatter medium. Our platform contributes a miniaturized and data-efficient solution to design a resource-limited multi-function microscope.