SP 15000 NG homodyne interferometer

The 1 beam flat mirror interferometer (SP-NG series), developed by SIOS GmbH, is a homodyne interferometer (1 wavelength only) powered by a frequency-stabilized Helium Neon laser. The SIOS single-beam interferometer measures the distance between the object (plane mirror) and the interferometer with very high resolution. An optical fiber carries the source to the interferometer, enabling it to be positioned “as close as possible” to the mirror to be measured. The laser wavelength is corrected for environmental conditions (temperature, pressure and humidity). Mirror displacement is converted into two sinusoidal quadrature signals directly proportional to displacement. By fringe counting and interpolation, it is thus possible to achieve sub-nanometer resolutions. Specific software is used for data processing, display and storage.