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Updated: May 16, 2026

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
Published on: January 28, 2019
Detection of interference phase by digital computation of quadrature signals in homodyne laser interferometry
Simon Rerucha1, Zdenek Buchta, Martin Sarbort
1Institute of Scientific Instruments of the ASCR, Kralovopolska 147, 612 64 Brno, Czech Republic. res@isibrno.cz
Abstract:
We have proposed an approach to the interference phase extraction in the homodyne laser interferometry. The method employs a series of computational steps to reconstruct the signals for quadrature detection from an interference signal from a non-polarising interferometer sampled by a simple photodetector. The complexity trade-off is the use of laser beam with frequency modulation capability. It is analytically derived and its validity and performance is experimentally verified. The method has proven to be a feasible alternative for the traditional homodyne detection since it performs with comparable accuracy, especially where the optical setup complexity is principal issue and the modulation of laser beam is not a heavy burden (e.g., in multi-axis sensor or laser diode based systems).
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