These instruments feature accurate and absolute measurements of prisms angles from 0° to 360° either in reflection or in transmission. It incorporates an ultra-accurate air bearing rotary table and a high precision rotary encoder with accuracy in the subarcsec range. The system also includes an electronic autocollimator mounted on a tiltable base. The rotary and the electronic autocollimator provide absolute angle indication of any angle between 0°and 360°.

This instrumentation line is an absolute angle measuring instrument as well equipped with a precision mechanical rotary table. Dimensions of the rotary table and of the autocollimators are smaller, the accuracy of the angular encoder is in the arcsec range. The applications are related to the measurement of small optical components, micro-prisms, etc. Otherwise, the features and measuring principle are similar with the Absolute Line.

The Comparison Line includes precision angle measurement instruments - also known as Comparison Goniometers - primarily used to measure prisms and other plano optical components in production environment. These instruments can measure any angles, however, using a reference prism with a known angle. The first reference measurement is done using the master prism. Further measurements are made relatively to the angle of the master prisms. The results are given as difference to the master prism or as absolute value of the measured angle. An exception are the 90° - prisms angles which can be measured absolutely without the need of a master prism.