Opt Express. 2023 Feb 13;31(4):6730-6740. doi: 10.1364/OE.479544.
We report what is believed to be the first example of fully continuous, 24-hour vertical monitoring of atmospheric optical turbulence. This is achieved using a novel instrument, the 24-hour Shack-Hartmann Image Motion Monitor (24hSHIMM). Optical turbulence is a fundamental limitation for applications such as free-space optical communications, where it limits the achievable bandwidth, and ground-based optical astronomy, restricting the observational precision. Knowledge of the turbulence enables us to select the best sites, design optical instrumentation and optimise the operation of ground-based optical systems. The 24hSHIMM estimates the vertical optical turbulence coherence length, time, angle and Rytov variance from the measurement of a four-layer vertical turbulence profile and a wind speed profile retrieved from meteorological forecasts. To illustrate our advance we show the values of these parameters recorded during a 36-hour, continuous demonstration of the instrument. Due to its portability and ability to work in stronger turbulence, the 24hSHIMM can also operate in urban locations, providing the field with a truly continuous, versatile turbulence monitor for all but the most demanding of applications.
我们报告了一个被认为是首次实现大气光学湍流全连续、24 小时垂直监测的实例。这是使用一种新型仪器，即 24 小时 Shack-Hartmann 像移监测仪（24hSHIMM）实现的。光学湍流是自由空间光通信等应用的基本限制因素，它限制了可实现的带宽，以及地基光学天文学，限制了观测精度。对湍流的了解使我们能够选择最佳的站点，设计光学仪器，并优化地面光学系统的运行。24hSHIMM 通过测量四层垂直湍流廓线和从气象预报中检索到的风速廓线，估算垂直光学湍流相干长度、时间、角度和 Rytov 方差。为了说明我们的进展，我们展示了在 36 小时连续演示仪器期间记录的这些参数的值。由于其便携性和在较强湍流中工作的能力，24hSHIMM 还可以在城市环境中运行，为该领域提供了一种真正连续、通用的湍流监测仪，适用于除最苛刻应用之外的所有应用。
