Investigation of optical knife edge sensor for low-cost, large-range and dual-axis nanopositioning stages

We analyzed the parameter effects of an optical knife-edge sensor (OKES) and the measurement uncertainty to achieve high linearity, long range, and high accuracy for nanopositioning stage applications. The OKES utilizes interference fringes produced from diffraction across the knife-edge. The total field at the detector was calculated from superposition of the incident field and the diffracted field at the knife-edge, and the edge diffraction...