Metrology is a key aspect of any measurement technique since the information about the error is the enabling factor for their utility and developments. Quantitative phase imaging (QPI) benefit from metrology in particular, as new approaches to system design, data processing and relevant feature extraction methods require constant validation and improvements. QPI in biomedical applications span a wide range of measurement challenges ranging from sub-µm features in monolayer of cells to cm2 cell cultures, free-floating and three-dimensional cell clusters or even whole organisms. In this work we show how to create phantoms that strive to mimic all kinds of said specimens and their interaction with light, ultimately providing tool for validation and benchmarking a variety of QPI systems. We exploit many degrees of freedom provided by the two-photon polymerization technique–most notably three-dimensional shape and size, refractive index modulation and adjustable scattering properties–in order to design and fabricate various phantoms that resemble real biological microobjects, recreate the challenges of the particular measurement scenario and finally provide invaluable data for metrological analysis.
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