Direct visualization of vibration modes of microobjects using an LCoS SLM in a Twyman-Green interferometer


  • Jacek Kacperski Warsaw University of Technology
  • Malgorzata Kujawinska Warasw University of Technology



The modification of a classical Twyman-Green interferometer by implementation of Liquid Crystal on a Silicon (LCoS) Spatial Light Modulator (SLM) as a reference mirror allows introducing an arbitrary phase in the reference wavefront. This special capability is applied to facilitate the measurements of mechanically active microelements (MEMS). Thanks to compensation of the initial shape of an element under test, it is possible to directly visualize vibration mode shapes even for non-flat objects and determine resonance frequencies of microelements. The description of the measurement system, methodology of the visualization and selected results obtained for a silicon micromembrane are presented.

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Author Biography

Malgorzata Kujawinska, Warasw University of Technology

SPIE Fellow, Professor of applied optics at Warsaw University of Technology, head of Optical Engineering Division at Institute of Micromechanics and Photonics, recognized expert on full-field optical metrology, image processing and hybrid experimental-numerical methods in experimental mechanics, material engineering, reverse engineering and multimedia. Author of more than 200 papers and leader of 6 European Projects and numerous of national projects for the Ministry of Science and Higher Education as well as for industry




How to Cite

J. Kacperski and M. Kujawinska, “Direct visualization of vibration modes of microobjects using an LCoS SLM in a Twyman-Green interferometer”, Photonics Lett. Pol., vol. 2, no. 1, pp. pp. 49–51, Mar. 2010.