3D Displacement Measurement with Pico-Meter Resolution Using Single Heterodyne Grating Interferometry
The precision positioning device becomes significant requirement in scientific instruments used for the applications of nanotechnology for a few decades. To achieve the high resolution positioning, the sensing methods of displacement sensor become more important in positioning device. In this paper, a novel method is presented for measuring both in-plane/out-plane displacements with the single heterodyne grating interferometry (HGI). We demonstrated the 1D, 2D, and 3D measurement results respectively and the smallest displacement can be detected was better than 6 pm. Furthermore, the nanometer resolution can be ensured within 20 µm displacement. Hence, the in-plane/out-plane measurements with single apparatus can be realized by our method and might be a displacement sensor using in the motorized stage with suitable opto-mechanics structure minimization.
Wei Gao, Yasuhiro Takaya, Yongsheng Gao and Michael Krystek
C. C. Hsu et al., "3D Displacement Measurement with Pico-Meter Resolution Using Single Heterodyne Grating Interferometry", Key Engineering Materials, Vols. 381-382, pp. 283-286, 2008