Recent activities at PTB nanometer comparator

The PTB in cooperation with the Dr. Johannes Heidenhain GmbH built up a new length comparator with a measurement range of 610 mm for 1D length measurements on line scales, linear encoders and interferometers. The PTB nanometer comparator was retrofitted and now allows a stable operation of the interferometer. To investigate the actual measurement performance a few line scales and a linear encoder were measured and compared with results from other comparators. The results are discussed and recent developments at the nanometer comparator are described.