Multi-mode microscopy in real-time with LED array illumination

Brightfield, darkfield and phase contrast are three of the most popular imaging modalities in biological microscopy. Each provides visualization of different sample properties, without fluorescent labels or staining. We demonstrate here a single-camera imaging system that can simultaneously acquire brightfield, darkfield and phase contrast images in real-time. Our method uses a programmable LED array as the illumination source, which provides flexible patterning of illumination angles. We achieve a frame rate of 50 Hz with 2560 x 2160 pixels of lateral resolution, with speed being limited by the camera.