Suppression of self-focusing through low-pass spatial filtering and relay imaging.
Suppression of self-focusing through low-pass spatial filtering and relay imaging.
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DOI：
10.1364/ao.17.002053
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发表时间：
1978-07
期刊：
影响因子：
1.9
通讯作者：
J. Hunt;J. Glaze;W. Simmons;P. Renard
中科院分区：
文献类型：
--
作者：
J. Hunt;J. Glaze;W. Simmons;P. Renard
大功率激光放大器中的自聚焦效应表现为小尺度光束不稳定性和大尺度相位畸变。空间滤波已被证明可以控制不稳定性;空间滤波器也构成用于图像中继的适当的透镜对元件。在本文中，图像中继作为一种技术，保持横向强度分布的高功率光束，因为它通过非线性元件长距离传输。因此，放大器孔径可以更有效地填充，导致固定孔径系统性能加倍。空间滤波器的带通的最佳选择的理由。正如预期的那样，这种选择取决于光束进入任何滤波器时的空间结构的细节。一个几何光学的方法是使用整个;然而，推导出的结果仍然有效时，衍射。
Self-focusing effects in large, high power laser amplifiers become manifest as small-scale beam instabilities and as large-scale phase aberrations. Spatial filtering has been shown to control instabilities; spatial filters constitute appropriate lens pair elements for image relaying as well. In this paper, image relaying is presented as a technique for preserving the transverse intensity profile of a high power beam as it propagates long distances through nonlinear elements. As a consequence, amplifier apertures can be filled more effectively, leading to a doubling of fixed-aperture system performance. A rationale for optimal selection of spatial filter bandpass is also presented. This selection, as might be expected, depends upon details of the beam's spatial structure as it enters any filter. A geometrical optics approach is used throughout; nevertheless, derived results remain valid when diffraction is included.