High-accuracy absolute distance measurement by two-wavelength double heterodyne interferometry with variable synthetic wavelengths

Yoshiyuki Kuramoto; Hiroshi Okuda

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arXiv · 1402.5575

High-accuracy absolute distance measurement by two-wavelength double heterodyne interferometry with variable synthetic wavelengths

Yoshiyuki Kuramoto·Hiroshi Okuda

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Abstract

We present an absolute distance measurement interferometer based on a two wavelength interferometer and a variable synthetic wavelength technique. The wavelength scanning range was 12 GHz, realized with a phase accuracy of 1.0 m{\lambda} by heterodyne detection at each measurement wavelength. This small wavelength scanning range enabled the use of distributed feedback laser diodes as an interferometer light source and a fast 20 ms wavelength scanning time by injection current control. We demonstrated a measurement range of up to 1.5 m and an accuracy better than 1.2 nm in comparison with a displacement measurement interferometer, corresponding to a relative accuracy of 10-9. In addition, we also proposed expanding the range of maximum measurement and compensation of refractive index of air for linear colliders.

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Yoshiyuki Kuramoto, Hiroshi Okuda. 2014-02-23. High-accuracy absolute distance measurement by two-wavelength double heterodyne interferometry with variable synthetic wavelengths. https://arxiv.org/abs/1402.5575

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