Compact and accurate concept of laser wavemeters based on ellipsometry

K Ouedraogo; S Topsu; L Chassagne; P Ruaux; B Cagneau; Y Alayli

doi:10.1063/1.3585975

Compact and accurate concept of laser wavemeters based on ellipsometry

Rev Sci Instrum. 2011 May;82(5):055102. doi: 10.1063/1.3585975.

Authors

K Ouedraogo¹, S Topsu, L Chassagne, P Ruaux, B Cagneau, Y Alayli

Affiliation

¹ LISV/University of Versailles, 78035 Versailles, France.

PMID: 21639533
DOI: 10.1063/1.3585975

Abstract

Common laser wavemeters are based on a scanning Michelson interferometer. Displacements of the moving mirror as long as tens of centimeters are needed to reach a relative accuracy of 1 × 10(-6) (1σ) on the unknown laser wavelengths. Such a long displacement range makes the system very sensitive to mechanical vibrations and to misalignments of the laser beams. The purpose of this paper is to demonstrate a new concept of laser wavemeter based on the measurements of the ellipsometric parameters ψ and Δ of the laser beams. Experimental results show that a 10(-6) (1σ) accuracy level could be reach with a displacement range of only 4 μm. Implementations of the device are described. Comparisons between our polarimetric wavemeter and a calibrated wavemeter are presented for two lasers, an extended cavity laser diode at 656 nm and a 532 nm green line Nd:YAG laser.