Modeling and verifying non-linearities in heterodyne displacement interferometry

S.J.A.G. Cosijns, H. Haitjema, P.H.J. Schellekens

Research output: Contribution to journalArticleAcademicpeer-review

141 Citations (Scopus)


The non-linearities in a heterodyne laser interferometer system occurring from the phase measurement system of the interferometer andfrom non-ideal polarization effects of the optics are modeled into one analytical expression which includes the initial polarization state ofthe laser source, the rotational alignment of the beam splitter along with different transmission coefficients for polarization states and therotational misalignment of the receiving polarizer. The model is verified using a Babinet Soleil Compensator allowing a common path forboth polarization states and thereby reducing the influence of the refractive index of air. The verification shows an agreement of the modelwith measurements with a standard deviation of 0.2 nm. With the use of the model it is confirmed that the mean of two polarizer receiverscan reduce the effect of non-linearity. However, depending on the accuracy of the polarizer angles, a second-order non-linearity remains.Also the effect of rotational misalignment of the beam splitter can not be reduced in this way.
Original languageEnglish
Pages (from-to)448-455
JournalPrecision Engineering
Issue number4
Publication statusPublished - 2002


Dive into the research topics of 'Modeling and verifying non-linearities in heterodyne displacement interferometry'. Together they form a unique fingerprint.

Cite this