A new fringe subdivision method that employs a large synthetic wavelength to subdivide fringes formed by a small single wavelength is proposed. Based on this subdivision method, we demonstrate a novel dual-wavelength interferometric technique with subnanometric resolution, whose potential fringe subdivision factor derived from an evaluation of the interferometer can reach up to 1/440,000. Theoretical analysis and experimental results with a resolution of 0.05 nm are presented to show the feasibility of the interferometric technique.
展开▼
