Angle Measurement of 90°-Prisms
The 90° and 45° error of 90° prisms is measured in two steps. In the first step, the error of the 90° angle is measured. In the second step, the deviation of the 45° angle is determined. Like the wedge error measurement with double cross, this application is based on multiple cross evaluation and is therefore subject to the limitation that this requires a separation of the autocollimation images in the order of the minimum detectable angle difference. These can be taken from the technical data of the ELCOMAT® direct product line. This results in a lower limit for the measurability of the deviation of the 90° and 45° angles.