Instrument layout (a) showing the trapping beam (purple), illumination path for brightfield imaging (orange), fluorescence excitation beam (red), fluorescence emission (green), charge-coupled device (CCD) camera, electron-multiplying charge coupled device (EM-CCD) camera, dichroic mirrors (D1 and D2), mirrors (M1 and M2), and lenses (L1, L2, L3, L4). All other components of the trap-confocal microscope system are labeled in the figure. (b) Detailed schematic of a trapped pathogen (green) is shown. The laser light (purple) refracts through the pathogen, creating a momentum change (red, labeled Fa and Fb), pushing the pathogen up and into the focused trapping beam. As the pathogen is trapped, it can then be positioned next to a phagocytic cell (blue) where the cell surface proteins on the pathogen can engage in receptors on the phagocytic cell surface.