Resolution-enhanced Fourier ptychographic microscopy based on high-numerical-aperture illuminations

• Published in: Scientific reports Vol. 7; no. 1; pp. 1187 - 11
• Main Authors: Sun, Jiasong, Zuo, Chao, Zhang, Liang, Chen, Qian
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 26-04-2017; Nature Publishing Group; Nature Portfolio
• Subjects: 639/624/1107/328/2238; 639/624/1107/510; High-throughput screening; Humanities and Social Sciences; Immersion; Microscopes; Microscopy; multidisciplinary; Science; Science (multidisciplinary); Spatial discrimination
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-01346-7

High-resolution and wide field-of-view (FOV) microscopic imaging plays a central role in diverse applications such as high-throughput screening and digital pathology. However, conventional microscopes face inherent trade-offs between the spatial resolution and FOV, which are fundamental limited by the space-bandwidth product (SBP) of the optical system. The resolution-FOV tradeoff can be effectively decoupled in Fourier ptychography microscopy (FPM), however, to date, the effective imaging NA achievable with a typical FPM system is still limited to the range of 0.4–0.7. Herein, we report, for the first time, a high-NA illumination based resolution-enhanced FPM (REFPM) platform, in which a LED-array-based digital oil-immersion condenser is used to create high-angle programmable plane-wave illuminations, endowing a 10×, 0.4 NA objective lens with final effective imaging performance of 1.6 NA. With REFPM, we present the highest-resolution results with a unprecedented half-pitch resolution of 154 nm at a wavelength of 435 nm across a wide FOV of 2.34 mm
2
, corresponding to an SBP of 98.5 megapixels (~50 times higher than that of the conventional incoherent microscope with the same resolution). Our work provides an important step of FPM towards high-resolution large-NA imaging applications, generating comparable resolution performance but significantly broadening the FOV of conventional oil-immersion microscopes.