Design of a nano-measurement system based on dual Fabry-Perot interferometer

A new nano-measurement system with laser, dual Fabry-Perot interferometers (DFPI), tapping stylus, flexure hinge stage and digital PID real-time computer control system is systematically designed. The theoretical basis of the nano-measurement system, using the measurement of amplitude difference or equal amplitude time interval of DFPI transmission wave, is proposed. The method of detection of tapping stylus vibration is theoretically analyzed. The finite element analysis method of small distance stage based on flexure hinge structure is proposed. The digital PID closed loop control system with the feedback signal of capacitance position sensor is applied, the system nonlinear influence caused by piezoelectricity element was solved. Finally, system error is analyzed.