Research on field calibration device of Femto-Joule level laser energy

Abstract

In order to solve the problem that the field calibration technology of pulsed laser micro-energy is not complete, which makes it difficult to calibrate the pulse energy parameters of Femto-Joule level pulsed laser source output, the field calibration device of Femto-Joule level laser energy is developed by using the principle of analog integral. By establishing the mathematical model and numerical simulation analysis of the photoelectric detection module, the device optimizes the cutoff frequency of the photoelectric detection module, reduces the minimum detectable power of the photoelectric detection module to 6.7nW, improves the micro-energy laser detection capability, reduces the transmission bandwidth and complexity, and improves the equipment integration and anti-interference ability to meet the requirements of field measurement and calibration. At the same time, the device adopts the integral circuit structure based on the transconductance amplifier, analyzes the relationship between the integral window time and the integral error through the numerical simulation method, accurately controls the integral window time, reduces the integral error to 4%, effectively suppresses the stray light interference, and improves the field measurement accuracy of Femto-Joule level pulsed laser energy measurement is improved. In order to comprehensively examine the performance of the field calibration device of Femto-Joule level laser energy, an experimental verification device is designed, and the verification and calibration tests are carried out. The test results show that the field calibration device of Femto-Joule level laser energy can accurately measure the laser energy value of pulse with 1ns~100ns pulse width. The energy measurement range of the device is 10fJ~1pJ, and the measurement uncertainty is 14% (k=2), The technical parameters of the device can meet the requirements of field calibration of Femto-Joule level laser energy.