Journal of the Korean Society for Precision Engineering (한국정밀공학회지)
- Volume 15 Issue 12
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- Pages.169-179
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- 1998
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- 1225-9071(pISSN)
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- 2287-8769(eISSN)
Orthogonality Measurement of Square Plane Mirrors for Laser Interferometry
레이저 간섭계의 직각 평면거울에 대한 직각도 오차 측정
Abstract
Plane mirror type laser interferometers are popularly being used in many modern ultraprecision machines, as they can perform simultaneous measurements of multiple axis positions with nanometer resolution capabilities. One important issue in this application of laser interferometers is to provide a good level of alignment between the reflecting mirrors and the laser beams so that measurement errors due to undesirable coupling effects can be avoided in multiple axis measurements In this investigation, a thorough metrological analysis is given to develop an suitable mathematical model for a precision x-y stage in which the orthogonality misalignment between the reflecting mirrors significantly affects overall x-y mea-surement results. Then a noble calibration method is suggested in which two-dimensional displacement sensors of moire gratings of concentric circles are used to realize the reversal principle of orthogonality evaluation in situ. Finally, actual experimental results are discussed to verify that the suggested method can effectively calibrate the orthogonality error with an uncertainty of 0.2667 arcsec.
Keywords
- reversal principle;
- orthogonality error;
- x-y stage;
- plane mirror interferometry;
- moire grating of concentric circles
- 반전법;
- 직각도오차;
- x-y 스테이지;
- 평면거울간섭계;
- 동심원 모아레 격자;