CAREER: In Situ Study of Aerosols in the Coarse Mode With Digital Holography

职业：利用数字全息术对粗模式气溶胶进行原位研究

• 批准号: 1665456
• 负责人: Matthew Berg
• 金额: $ 76.8万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-16 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1665456&HistoricalAwards=false
• 关键词: CAREER; Situ; Study; Aerosols; Coarse

This study seeks to develop and apply new concepts in digital holography to obtain three-dimensional images of airborne particles, called "coarse mode aerosols" (CMAs). These aerosols are a major source of uncertainty for radiative impacts in climate models. The planned research will use a pioneering digital holographic design, developed by the PI, to measure various optical parameters of these aerosols. The associated education plan in this CAREER award will integrate hands-on teaching in a research lab setting and the development of online modules based on the planned research. The overall planned research and educational components seek to recruit underrepresented minority students and provide a unique learning opportunity in applied optics through the university's Expanding Diversity in Astronomy and Physics Program (ED-APP). This study seeks to establish a new characterization paradigm that is free from the drawbacks of conventional light scattering and can unambiguously describe CMA particle size and shape. Optical observables will be automatically measured, which include the angular scattering pattern, total cross sections and single scatter albedo. A series of digital holographic experiments will be used to image CMAs with particle sizes of the order of 1-300 microns. A new analysis method will then be used to quantify the particle size and shape distributions. From these measured particle holograms, accurate estimates of optical observables will be extracted. The goal of this research is to solve the inverse problem, by removing the long standing difficulty relating scattering measurements to particle properties. The study also seeks to correlate particle morphology with optical observables - of critical importance in many remote sensing applications. A portable version of the laboratory holographic instrumentation will be developed for field studies. The goal here is to apply the same techniques in urban and agricultural environments.

这项研究旨在开发和应用数字全息术的新概念，以获得空气中颗粒的三维图像，称为“粗模式气溶胶”（CMA）。 这些气溶胶是气候模型中辐射影响不确定性的主要来源。 计划中的研究将使用 PI 开发的开创性数字全息设计来测量这些气溶胶的各种光学参数。 该职业奖的相关教育计划将整合研究实验室环境中的实践教学以及基于计划研究的在线模块的开发。 总体规划的研究和教育部分旨在招收代表性不足的少数族裔学生，并通过大学的天文学和物理多样性扩展计划（ED-APP）提供应用光学方面独特的学习机会。 本研究旨在建立一种新的表征范式，该范式摆脱了传统光散射的缺点，并且可以明确地描述 CMA 颗粒尺寸和形状。 光学观测值将被自动测量，包括角散射图案、总横截面和单散射反照率。 一系列数字全息实验将用于对粒径为 1-300 微米量级的 CMA 进行成像。 然后将使用一种新的分析方法来量化颗粒尺寸和形状分布。 从这些测量的粒子全息图中，将提取光学可观测值的准确估计。 这项研究的目标是通过消除将散射测量与粒子特性联系起来的长期存在的困难来解决反问题。 该研究还试图将粒子形态与光学可观测值联系起来——这在许多遥感应用中至关重要。 将开发便携式版本的实验室全息仪器用于现场研究。 这里的目标是在城市和农业环境中应用相同的技术。

项目成果

Imaging aerosols with digital holography

利用数字全息技术对气溶胶进行成像

• 发表时间: 2018
• 期刊: Physics today
• 影响因子: 3.5
• 作者: M. J. Berg, Y. W.