Abstract: An instrument is disclosed for dilating the pupil of an eye. The instrument includes a handle and a switch mounted on the handle for alternating between first and second states. A retractable dilator mechanism is attached to the switch and is extendible from the handle. The dilator mechanism selectively alternates between a retracted condition when the switch is in a first state and an expanded condition when the switch is in its second state. The dilator mechanism includes hooks, a nylon ribbon or an inflatable spiral tube for engaging a plurality of points along an inside edge of the pupil and urging the pupil into a dilated condition when the dilator mechanism is expanded.