Method for calibrating a measured value of detecting means

A calibration method for a detecting device in which a physical value, measured by the detecting device incorporated into an apparatus, is calibrated, comprising the steps of:

• prior to installation of the detecting device in the apparatus, inputting a plurality of previously-known physical values into the detecting device;
• outputting measured values of the previously-known physical values from the detecting device;
• storing in a memory data of differences between the previously-known physical values and the measured values of the previously-known physical values in correspondence with said measured values of the previously-known physical values, wherein the number of sets of the data stored is such that non-linear approximation can be conducted between the previously-known physical values and the measured values thereof;
• and
• after installation of the detecting device in the apparatus, calibrating a physical value measured by the detecting device by adding thereto a value estimated from the differences stored in the data retrieved based on the physical value to be calibrated.