Adjustable dispersion reduction in low-coherent techniques by a system of tilted metallic mirrors with dielectric coating

作者：Tomczewski S^*; Salbut L

来源：Optics and Lasers in Engineering, 2015, 68: 121-125.

DOI：10.1016/j.optlaseng.2014.12.017

• Low-coherence interferometry
• Optical coherence tomography
• Dispersion compensation

In this paper a new method for adjustable reduction of a dispersive drop in axial resolution during low-coherent measurements is presented. This method is based on multiple reflections of a light beam from dielectric coated metallic mirrors and is intended for reducing dispersion in full-field systems. The tilted metallic mirror with a dielectric coating works like an adjustable Gires-Toumois interferometer. The concept of adjustability is based on a polarization dependent phase shift upon reflection from metallic surfaces at incidence angles different from theta(1)=0 degrees. The dispersion compensation was simulated numerically with the use of Fresnel equations for a silver mirror based compensator. The possibility of dispersion reduction was then verified experimentally in a Twyman-Green interferometer showing over 40% improvement in the axial resolution.

• 出版日期2015-5