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arXiv · 1203.5858

Spatial Filter with Volume Gratings for High-peak-power Multistage Laser Amplifiers

Yi-zhou Tan·Yi-sheng Yang·Guang-wei Zheng·Ben-jian Shen·Heng-yue Pan·Liu Li
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Abstract

The regular spatial filters comprised of lens and pinhole are essential component in high power laser systems, such as lasers for inertial confinement fusion, nonlinear optical technology and directed-energy weapon. On the other hand the pinhole is treated as a bottleneck of high power laser due to harmful plasma created by the focusing beam. In this paper we present a spatial filter based on angular selectivity of Bragg diffraction grating to avoid the harmful focusing effect in the traditional pinhole filter. A spatial filter consisted of volume phase gratings in two-pass amplifier cavity were reported. Two-dimensional filter was proposed by using single Pi-phase-shifted Bragg grating, numerical simulation results shown that its angular spectrum bandwidth can be less than 160urad. The angular selectivity of photo-thermo-refractive glass and RUGATE film filters, construction stability, thermal stability and the effects of misalignments of gratings on the diffraction efficiencies under high-pulse-energy laser operating condition are discussed. Keywords: spatial filter, pinhole spatial filter, RUGATE filter, angular selectivity of volume phase grating, Pi-phase-shifted Bragg grating, high-energy pulsed laser, multi-pass laser amplifier

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Yi-zhou Tan, Yi-sheng Yang, Guang-wei Zheng, Ben-jian Shen, Heng-yue Pan, Liu Li. 2012-03-27. Spatial Filter with Volume Gratings for High-peak-power Multistage Laser Amplifiers. https://arxiv.org/abs/1203.5858

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