A thermally-stable setup and calibration technique for 2D sensors

A novel thermally stable calibration setup for 2D sensors is presented. It uses laser encoders with compensation for environmental conditions as reference sensors. The metrology frame of the setup has been manufactured in a near-zero thermal expansion material (Zerodur) and an adequate metrological design has been applied. These features allow the system to be stable in different thermal conditions. The system has been used to characterize a 2D measuring system, a cross grid encoder, at different temperatures. Although most of the geometrical errors and the thermal influence have been minimized, other sources of uncertainty remain. Their influence on the final uncertainty is presented.