A lens-free single-shot fluorescent imaging system using CMOS image sensors with dielectric multi-layer filter

This paper reports a lens-free single-shot fluorescent imaging system based on CMOS image sensors, for monitoring the shape of a single cell in the cluster during culture in parallel. By directly depositing a dielectric multi-layer filter to eliminate excitation light on a CMOS image sensor, the spatial resolution of smaller than 10 μm was achieved, which is small enough to distinguish fluorescent characteristics for single cell level. As one of the typical demonstrations, rat primary neurons and human colon cancer cells stained with Hoechst^® 33342 were observed and their individual nuclei were distinguished in the fluorescent image.