Abstract: A protective cover for medical imaging devices of the type having a probe with an optical system at a distal end includes a sheath of plastic material formed to enclose at least a portion of the probe and a transparent head secured to the sheath at a distal end of the cover. The transparent head provides a transparent window at the distal end of the probe to allow light to enter the probe and be imaged in a normal manner. Indicia are formed on the transparent head and are imaged by the medical imaging device. The image is then analyzed to determine if the indicia as shown in the image correspond to a preselected pattern, which may be one of a group of patterns which provide indications concerning the nature of the cover. If a pattern is recognized, the information corresponding to that pattern can be provided to an operator; if no pattern is recognized or if the pattern corresponds to an improper cover for the particular imaging device, a warning can be provided to the operator or the device disabled.