Design of Metrological Device for Synchronous Acquisition of Laser Interferometry Measurement Signals

To enhance the consistency and accuracy of multi-measurement-axis signal synchronous acquisition to meet the requirements of high-precision measurement applications, a multi-channel laser interferometry signal synchronous acquisition metrology device based on the VPX architecture has been developed. This device features an interconnection backplane and signal processing board card based on the VPX architecture, achieving a modular design that is easy to expand and maintain. A two-stage clock distribution network based on a dual-loop clock jitter cleaner is designed to synchronize the clocks of on-board and inter-board devices of the signal processing board card. A JESD204B interface is designed to synchronously distribute the reference optical signal conversion data between the board cards. Based on the above design work, the performance of the synchronous acquisition hardware platform was tested by simulating the laser interferometry measurement signal after photoelectric conversion using a signal generator. The measurement results show that the maximum time deviation of each channel within the signal processing board card is 21.69 ps, and the maximum time deviation between each channel of the signal processing board cards is 32.85 ps, which is better than the ±200 ps time deviation index of the US Zygo-4104 series board cards.