Gauge-block calibration system:

The LM 20 laser-interferometric gauging probe is established as an upper gauging probe for the calibration of parallel gauge blocks. Easy to use software for data processing, data correction and data output in compliance with the existing standards is available.

  • Significant reduction of the required quantity of standard gauge blocks
  • Linearity errors, e. g. errors due to misalignments, angular misalignments of the gouging probe and thermal effects will be corrected.
  • Yields faster measurements, thanks to menu-driven metrological procedures
  • Calibrating of unusual nominal sizes and items is possible

Download datasheet here.


  • Calibration of plane-parallel gauge blocks with rectangular cross sections ranging from 0.5 mm to 100 mm, Measurement characteristic dimensional parameters in compliance with ISO 3650.
  • Using the LM 20 laser-interferometric gauging probe as upper gauging probe a high measurement accuracy and linearity over the measurement range of 20 mm is achieved.
  • According to a PTB recommendation (German national bureau of standards), the total number of reference-standard gauge blocks may be reduced to fifteen.

Technical Data:

  • Measuring range: 0.5 mm… 100 mm

SIOS Model LM 20 laser-interferometric gauging probe:

  • Measuring range: 20 mm
  • Resolution: 1 nm
  • Uncertainty: ≤ ±10 nm over 15 mm
  • Measuring force: 1 N