The rangefinding telemeter (or simply telemeter or rangefinder, depending on the context), is a device used to measure distances to remote objects, that is, a type of rangefinder. The name is derived from the Ancient Greek: τῆλε tēle "far away" and μέτρον métron "something used to measure". Originally optical devices used in surveying, they soon found applications in other fields, such as photography and in the military. They were specially useful for finding the range of a target, such as in naval gunnery and anti-aircraft artillery.
