Single-shot multispectral quantitative phase imaging (QPI) using a diffractive optical processor

We present an all-optical diffractive processor that can perform snapshot multispectral quantitative phase imaging (QPI) of transparent, phase-only objects. By leveraging multiple layers of spatially-structured diffractive materials designed via deep learning, this all-optical processor can transform phase profiles of an input object at various spectral bands into desired spatial intensity variations measured by a monochrome focal plane array to rapidly obtain the multispectral QPI of the object. This framework provides a compact and power-efficient multispectral QPI solution that can operate at different parts of the electromagnetic spectrum by integrating these thin diffractive layers on top of existing image sensors.