A range finder is a dead reckoning instrument used to measure the distance to a target and perform trajectory calculations. Range finders come in various forms, often designed as a long cylindrical tube composed of an objective lens, an eyepiece, and a ranging knob, which are used to determine the distance to a target. Range finders are instruments designed based on the principles of optics, acoustics, and electromagnetics for the purpose of distance measurement. Laser Range Finder A laser range finder is an instrument that uses laser beams to accurately measure the distance to a target. During operation, the laser range finder emits a very narrow laser beam toward the target. The beam reflected by the target is received by a photoelectric component, and a timer measures the interval between emission and reception. The distance from the observer to the target is then calculated based on this time measurement.