A rangefinding device wherein a series of movable lines are created electronically via the use of a liquid crystal display and associated circuitry. When a target of a known size, such as a deer, is "bracketed" exactly between two of these lines, the correct yardage is indicated on another portion of...http://www.google.ca/patents/US4617741?utm_source=gb-gplus-sharePatent US4617741 - Electronic rangefinder for archery
