Design of Laser Energy Meter Calibration System

Abstract

In order to solve the calibration problem of the laser energy meter, a laser energy meter calibration system was designed. The system should be composed of laser source, beam splitter, beam expander, monitoring energy meter, standard energy meter, electric translation stage, optical platform, computer, data acquisition and analysis processing system and optical path installation accessories. The comparison method was used calibration. It is proposed to improve the technical indicators of the system from two aspects: solving the traceability of the laser energy meter calibration system and eliminating the influence of the change of laser energy over time on the measurement results. The measurement uncertainty of laser energy calibration is analyzed in detail. The system realizes a wide range of laser energy ranging from 10mJ to 40J, with a relative extended uncertainty of 2% ($k=2$), and directly traces the laser energy to the National Sub-standard of Pulsed Laser Energy. The system was used to calibrate and verify the E1000 40J laser energy meter of the Chinese Academy of Metrology and the 3SIGMA/J50-110-25ST laser energy meter of Coherent. The test results show that the laser energy meter calibration device can be used for the measurement calibration of the laser energy meter with $1.064\mu \mathrm{m}$ and the power measurement uncertainty below 2% ($k=2$). The establishment method and testing technology of the system can provide reference for the establishment of laser energy meter measurement standards.