An improved illuminator with an adjustable beam pattern to be worn by medical and dental professionals includes a housing, a light-emitting diode disposed in the housing outputting light through a distal opening in the housing, an achromatic doublet lens mounted in the opening in the housing, and a singlet lens disposed between the LED and the achromatic lens. The system permits the isolation of a suspected faulty HDD to allow diagnostics to be performed without impacting operation of the rest of the system. The feeding hopper includes a feeding hole and a feeding passage connected to the housing.