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arXiv · 1405.0226

Wide-field, high-resolution Fourier ptychographic microscopy

Guoan Zheng·Roarke Horstmeyer·Changhuei Yang
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Abstract

In this article, we report an imaging method, termed Fourier ptychographic microscopy (FPM), which iteratively stitches together a number of variably illuminated, low-resolution intensity images in Fourier space to produce a wide-field, high-resolution complex sample image. By adopting a wavefront correction strategy, the FPM method can also correct for aberrations and digitally extend a microscope's depth-of-focus beyond the physical limitations of its optics. As a demonstration, we built a microscope prototype with a resolution of 0.78 um, a field-of-view of ~120 mm2, and a resolution-invariant depth-of-focus of 0.3 mm (characterized at 632 nm). Gigapixel colour images of histology slides verify FPM's successful operation. The reported imaging procedure transforms the general challenge of high-throughput, high-resolution microscopy from one that is coupled to the physical limitations of the system's optics to one that is solvable through computation.

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Guoan Zheng, Roarke Horstmeyer, Changhuei Yang. 2014-05-01. Wide-field, high-resolution Fourier ptychographic microscopy. https://doi.org/10.1038/nphoton.2013.187

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