High-Accuracy autocollimator calibration by interferometric 2D angle generator

V. Heikkinen, V. Byman, M. Shpak, R. Geckeler, A. Just, M. Krause, M. Schumann, A. Lassila

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review


Autocollimators are excellent measuring tools for many applications, such as adjustments or characterizations of precision mechanics, optics and instruments. Autocollimators have several characteristic error sources due to misalignment or nonideality of the collimator lens, the light source and the sensor. To fully characterize errors related to simultaneous engagement of both measurement axes of the autocollimator a two directional angle generator is necessary. In this paper, VTT MIKES interferometric 2-directional small angle generator (I2D-SAG) with updated model for calibration of autocollimators is described. It generates angles around 2 orthogonal axes with high accuracy. The maximum range of the I2D-SAG is ±1000" for both axes. In calibration of a high quality autocollimator a standard uncertainty below 0.01" can be reached. In addition, preliminary results of a comparison of I2D-SAG and PTB Spatial Angle Autocollimator Calibrator (SAAC) instrument are presented. This is the first comparison between 2D autocollimator calibration systems. In this comparison, a good agreement was reached in characterization of an electronic autocollimator over 900"×900" range.

Original languageEnglish
Title of host publicationAdvances in Metrology for X-Ray and EUV Optics VIII
EditorsLahsen Assoufid, Haruhiko Ohashi, Anand Krishna Asundi
PublisherInternational Society for Optics and Photonics SPIE
ISBN (Print)978-1-5106-2911-0
Publication statusPublished - 9 Sep 2019
MoE publication typeA4 Article in a conference publication
EventAdvances in Metrology for X-Ray and EUV Optics VIII 2019 - San Diego, United States
Duration: 11 Aug 201912 Aug 2019

Publication series

SeriesProceedings of SPIE


ConferenceAdvances in Metrology for X-Ray and EUV Optics VIII 2019
CountryUnited States
CitySan Diego



  • Autocollimator
  • Calibration
  • Comparison
  • Interferometric
  • Small angle generator

Cite this

Heikkinen, V., Byman, V., Shpak, M., Geckeler, R., Just, A., Krause, M., Schumann, M., & Lassila, A. (2019). High-Accuracy autocollimator calibration by interferometric 2D angle generator. In L. Assoufid, H. Ohashi, & A. K. Asundi (Eds.), Advances in Metrology for X-Ray and EUV Optics VIII [1110903] International Society for Optics and Photonics SPIE. Proceedings of SPIE, Vol.. 11109 https://doi.org/10.1117/12.2531023