Baker K L, Homoelle D, Utterback E, Jones S M
Lawrence Livermore National Laboratory, Livermore, CA, USA.
Opt Express. 2009 Oct 26;17(22):19551-65. doi: 10.1364/OE.17.019551.
Several techniques have been developed to phase apertures in the context of astronomical telescopes with segmented mirrors. Phasing multiple apertures, however, is important in a wide range of optical applications. The application of primary interest in this paper is the phasing of multiple short pulse laser beams for fast ignition fusion experiments. In this paper analytic expressions are derived for parameters such as the far-field distribution, a line-integrated form of the far-field distribution that could be fit to measured data, enclosed energy or energy-in-a-bucket and center-of-mass that can then be used to phase two rectangular apertures. Experimental data is taken with a MEMS device to simulate the two apertures and comparisons are made between the analytic parameters and those derived from the measurements. Two methods, fitting the measured far-field distribution to the theoretical distribution and measuring the ensquared energy in the far-field, produced overall phase variance between the 100 measurements of less than 0.005 rad(2) or an RMS displacement of less than 12 nm.
在带有分段镜的天文望远镜背景下，已经开发出了几种用于孔径相位调整的技术。然而，对多个孔径进行相位调整在广泛的光学应用中都很重要。本文主要关注的应用是用于快点火聚变实验的多个短脉冲激光束的相位调整。在本文中，推导了诸如远场分布、可拟合测量数据的远场分布的线积分形式、包含能量或桶中能量以及质心等参数的解析表达式，这些表达式随后可用于对两个矩形孔径进行相位调整。使用微机电系统（MEMS）设备获取实验数据以模拟两个孔径，并对解析参数与测量得出的参数进行比较。两种方法，即将测量的远场分布拟合到理论分布以及测量远场中的环围能量，在100次测量中产生的总体相位方差小于0.005弧度²或均方根位移小于12纳米。
