Displacement measuring interferometer for sub-nano meter resolution

Abstract

In this presentation, the displacement measurement system using sinusoidal phase modulation interferometer and modified phase-locked loop is discussed. The modified phase-locked loop is specially developed phase-locked loop for sinusoidal phase modulation interferometer for improving the resolution. The 0.1 nm step displacement with 1 Hz results that the current resolution of the system is less than sub-nano meter order.

Keywords

• Displacement measurement
• Phase meter
• Sinusoidal modulation
• Phase-locked loop
• Pico meter