Multi-color flow cytometer with PIC-based structured illumination

We demonstrate a flow cytometer in which structured light illumination is used to attribute fluorescent and scattering signals to their excitation wavelength. A suitable multi-color light source emitting structured illumination patterns at 405, 488, 561 and 640 nm is developed based on a silicon nitride photonic integrated circuit and cytometry experiments are conducted with calibration beads. Performance metrics of the novel cytometer are compared with those of a mature, commercial device. While the experimental device still features a slightly higher sensitivity floor than the commercial one, all but the most weakly stained beads can be categorized. These promising results validate the feasibility of the proposed concept.