Light Wave Instruments

These instruments rely on propagation of modulated light waves. First this type of instrument was developed in Sweden and named as Geodimeter its range is up to 2.5 km during night while in day its range is up to 3 km. Accuracy of these instruments varies in range 0.5 mm to 5 mm/km distance. For civil engineering projects these instruments are also very useful.

The advantage of using EDM instruments is the accuracy and speed in measurement. Numerous obstacles to chaining are overcome automatically when these instruments are used.