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In Situ Measurement of Vacuum Window Birefringence using 25Mg+ Fluorescence
Published on: June 13, 2020
High-accuracy interferometer with a prism pair for measurement of the absolute refractive index of glass
Yasuaki Hori1, Akiko Hirai, Kaoru Minoshima
1National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8563, Japan. y-hori@aist.go.jp
Abstract:
We propose a variable-path interferometric technique for the measurement of the absolute refractive index of optical glasses. We use two interferometers to decide the ratio between changes in the optical path in a prism-shaped sample glass and in air resulting from displacement of the sample. The method allows precise measurements to be made without prior knowledge of the properties of the sample. The combined standard uncertainty of the proposed method is 1.6x10(-6).
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