Real-time measurement of two-linear and three-angular motion errors using a single optical linear encoder in a high precision stage Conference Paper uri icon


  • Optical linear encoders are widely used as positioning sensors because of high resolution and long working range. However, this kind of encoder cannot measure motion errors such as angular errors, pitch, yaw and roll as well as linear errors and it only shows the single displacement along the driving axis. In this paper, a simple and precise optical encoder-implemented multi-degree-of-freedom(DOF) motion measurement system was constructed. A PZT-driven nanostage with a stroke of 25 μm was used. In the frequency response, the stage showed a resonance frequency at 90 Hz. The dynamic characteristics of the stage along the driving axis were identified from the signal of each error and had a significant effect on the pitch motion due to resonance effect on the pitch motion.

author list (cited authors)

  • Lee, C. B., Kim, G. H., & Lee, S. K.

publication date

  • January 2011