Laser measuring systems which operate according to the shadow method are normally used for the diameter range up to about 300 mm.
Special OPTImess sensors have been developed for larger diameters. An OPTImess with two integrated receivers allows diameter measurement of steel floors with a radius difference of 2 m.
The accuracy of the measurement can be doubled by using two receivers. A measurement up to a diameter of 8 m is possible using four OPTImess sensors installed in a cooled housing. Three sensors measure the distance from the tube — starting from a fixed base. The distance values are picked up by OPTIcontrol and the diameter is determined. The measurement is also possible on red hot surfaces.