Proceedings of the Korean Society of Precision Engineering Conference (한국정밀공학회:학술대회논문집)
- 2003.06a
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- Pages.288-291
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- 2003
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- 2005-8446(pISSN)
Real-time Measurement and Compensation of Motion Errors Using Extended Twyman-Green Interferometry
확장 트와이만-그린 간섭계를 이용한 운동 오차의 실시간 측정 및 보상
Abstract
This paper presents an extended Twyman-Green interferometry that enables simultaneous and real-time measurement of 5-DOF motion errors of the translational moving stage. This method uses a null balancing technique in which two plane mirrors are used as target mirrors to generate an interferometric fringe utilizing the optical principles of Twyman-Green interferometry. Fringe is detected by 2D photodiode array for high-speed measurement. Errors are then independently suppressed by activation of piezoelectric actuators through real-time feedback control while the machine axis is moving. Experimental results demonstrate that a machine axis can be controlled with motion errors about 10 nm in linear displacement, 0.15 arcsec in angular displacement