A laser rangefinder typically consists of a laser emitter, a receiver, and a microprocessor. The laser emitter sends out a pulse of laser light, which hits the target and bounces back towards the receiver, which detects the returning light. The time it takes or phase shift for the pulse to travel to the target and back is measured by the microprocessor, which then calculates the distance to the target using the speed of light in the time-of-flight method or using the speed of light, phase change, and modulation frequency in the phase shift method.