An infusion pump has an optical cassette detection system for determining whether or not a cassette of an administration tubing set is properly loaded in the pump. Operation of the pump may be enabled or disabled based on a determination of the cassette detection system. The cassette detection system includes a light emitter and a corresponding photosensitive detector, and a window carried by the cassette that includes a fluorophore. When the cassette is properly loaded in the pump, an excitation light beam from the emitter enters the window and excites the fluorophore, causing emission light in a wavelength band distinct from that of the excitation beam to be transmitted out of the window for receipt by the detector. The detector signal is evaluated by signal evaluation electronics to determine if the signal level is above a predetermined threshold, indicating the cassette is loaded.
