Wan Xiaoke, Wang Ji, Ge Jian
Department of Astronomy, Bryant Space Science Center, University of Florida, Gainesville, Florida 32611, USA.
Appl Opt. 2009 Sep 10;48(26):4909-16. doi: 10.1364/AO.48.004909.
An actively stabilized interferometer with a constant optical path difference is a key element in long-term astronomical observation, and resolving interference fringe ambiguities is important to produce high-precision results for the long term. We report a simple and reliable method of resolving fringe ambiguities of a wide-field Michelson interferometer by measuring the interference visibility of a noncollimated single-frequency laser beam. Theoretical analysis shows that the interference visibility is sensitive to a subfringe phase shift, and a wide range of beam arrangements is suitable for real implementation. In an experimental demonstration, a Michelson interferometer has an optical path difference of 7 mm and a converging monitoring beam has a numerical aperture of 0.045 with an incidental angle of 17 degrees. The resolution of visibility measurements corresponds to approximately 1/16 fringe in the interferometer phase shift. The fringe ambiguity-free region is extended over a range of approximately 100 fringes.
具有恒定光程差的主动稳定干涉仪是长期天文观测中的关键元件，解决干涉条纹模糊性对于长期产生高精度结果很重要。我们报告了一种通过测量非准直单频激光束的干涉可见度来解决宽视场迈克尔逊干涉仪条纹模糊性的简单可靠方法。理论分析表明，干涉可见度对亚条纹相移敏感，并且广泛的光束布置适合实际应用。在一个实验演示中，迈克尔逊干涉仪的光程差为7毫米，会聚监测光束的数值孔径为0.045，入射角为17度。可见度测量的分辨率对应于干涉仪相移中约1/16条纹。无条纹模糊区域扩展到约100个条纹的范围。
