Detector-warning unit for correct computer monitor to user distance

摘要

Display (1), such as a computer monitor has a combined detector-warning unit (2) for measurement of the distance between the screen (1) and a user. The detector (2) emits an optical (e.g. LED) or audible alarm (loudspeaker) when the user is too close to the screen. The detector (2) is integrated with a monitor (1) or supplied as a separate unit (5). The power supply to the detector is by mains or battery and is separate or integral to the monitor's supply. The distance measurement process typically uses a passive infrared detector.