US Patent 9892311 Detecting unauthorized visitors

An unauthorized visitor system collects an image of a person detected in a room of a patient. The system identifies reference points on the person's face, for example, points along the cheeks, jowls, and/or brow. The system may compare the reference points to reference points of images associated with registered visitors. The system then determines, based on the comparison, if the person is a registered visitor. One or more designated recipients may be alerted if the person is not a registered visitor or if the person breaches a patient identification zone established around a particular patient. The system may also register the person in a database of visitors.