A high-precision telecentric lens, an air-cushioned rotary axis with an air-cushioned counter tip and a new correction method are intended to achieve minimal measurement deviations in the range of 200 nm for the process-reliable detection of roundness tolerances of up to 2 µm.

To measure the roundness, the image is recorded with RotaryScan HD during the movement of the rotary axis. Measuring points are determined from the images of the various rotational positions, which are then calculated to form a circle. With up to 400 measuring points per second and measuring deviations in the range of 200 nanometers, the accuracy of form measuring devices can be achieved with significantly less measuring time.