Measurement of far-field divergence angle for high-power laser facility with phi 250-mm aperture

摘要

Abstract: In this article, we present a laser far-field CCD diagnostic device, which consists of optical system with $Phi@250 mm aperture, the CCD image receive system connecting with a computer and a single pulse synchronous trigger system. The collected images are processed and displayed in real time by computer. A quasi-ideal plane wave at 1060 nm is used to test the characters of this diagnostic device. The experimental result shows that size of focal spot encompassing 70% laser energy is about 2.5 times of diffraction limit. The device has been successfully applied to high power laser facility. According to the practical measurement, the far-field divergence angle is less than 14 times of diffraction limit when output of high power laser facility is 200 J each beam. !5