Pixel-super-resolved lens-free quantitative phase microscopy

Lens-free on-chip microscopy (LFOCM) has been widely utilized in digital pathology, drug screening, pointof- care testing (POCT), and quantitative phase imaging (QPI) due to its high throughput imaging capability and compactness. Initially, coherent laser sources were used in LFOCM to generate interference fringes to reconstruct the intensity and phase information of an object. The use of partially coherent light-emitting diodes (LEDs) in LFOCM offers a more portable and cost-effective alternative to conventional coherent illumination sources. However, the coherence-gating effect from a relatively low degree of coherence may cause a blur of high-frequency information in holograms, leading to an inaccurate object recovery. Thus, we present a partially coherent illumination based pixel-super resolved lens-free quantitative phase microscopy (PCIPSRLFQPM), which not only compensates for the impact of low coherence without increasing the volume of the system but also suppresses the theoretical Nyquist–Shannon sampling resolution limit imposed by the sensor pixel size (0.9μm).