The basic Michelson interferometer (CA-1300) is upgraded to a technicalinterferometer. Length measurement with this homodyne laser interferometer isbased on electronic fringe counting. The quadrature detection technique is usedto determine the direction and step numbers of movement of one interferometermirror. A comparator digitalizes the measured signals. An event counterregisters the fringe numbers which are converted into real length.

CA-1302 Motorized Extension

Educational Objectives

l Industrial Application

l Calibration of a Translation Stage

l Calibration Record

l Environmental Conditions

The Technical Interferometer (CA-1300 + CA-1301) is extended by amotorized translation stage and a controller to demonstrate the calibration ofan unknown length. Via a PC a travel range is set, encoded by the controllerand forwarded to the translation stage. The value measured by theinterferometer is compared to the travelling distance and hence to the setvalue. Corrected for environmental conditions the interferometer value buildsthe calibration standard.