Development of Phase-Shifting Point Diffraction Interferometry with Fiber Point Sources
Development of Phase-Shifting Point Diffraction Interferometry with Fiber Point Sources
复制标题
光纤点源相移点衍射干涉测量技术的发展
DOI：
10.2493/jjspe.69.678
复制
发表时间：
2003
影响因子：
--
通讯作者：
M. Nakano
中科院分区：
文献类型：
--
作者：
Y. Oshikane;T. Kataoka;K. Endo;Akihiro Noguchi;H. Inoue;M. Nakano
本文介绍了一种新型的相移点衍射干涉仪（PS-PDI），采用2个光纤点光源，作为一种工具，用于测量表面的SOR和EUV反射镜的亚纳米精度使用可见光光学。在传统的干涉测量中，参考表面的形状精度决定了测量精度。因此，我们需要一个亚纳米精度的绝对参考表面。其中一个合格的表面是来自点光源的球面波阵面。所提出的PS-PDI系统使用2个单模光纤作为点光源。该系统应用于曲率半径为500 mm、直径为30 mm的商用球面凹面镜的测量。在波长为632.8nm的He-Ne激光器中，该反射镜的测量重复性约为3 nm。
This paper describes a novel phase-shifting point diffraction interferometer (PS-PDI) that employs 2 fiber-optic point sources, as a tool for measuring surfaces for SOR and EUV mirrors with sub-nanometer accuracy using visible light optics. In conventional interferometry, the figure accuracy of the reference surface determines the measurement accuracy. We therefore need an absolute reference surface with sub-nanometer accuracy. One of the qualified surfraces is a spherical wavefront which comes from point light source. The proposed PS-PDI system uses 2 single-mode optical fibers as point light sources. The system is applied to the measurement of a commercial spherical concave mirror with 500 mm in radius of curvature and 30 mm in diameter. The repeatability of measurement for the mirror is estimated to be about 3 nm in peak-to-valley value at the wavelength of 632.8 nm in He-Ne laser.