EAGER: Laser 4D light field thermoreflectance (TR) imaging for non-intrusive high accuracy temperature measurement of 3D targets with high spatial and high temporal resolutions

EAGER：激光 4D 光场热反射 (TR) 成像，可对具有高空间和高时间分辨率的 3D 目标进行非侵入式高精度温度测量

• 批准号: 1545546
• 负责人: Sy-Bor Wen
• 金额: $ 18.41万
• 依托单位: Texas A&M Engineering Experiment Station
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1545546&HistoricalAwards=false
• 关键词: EAGER; Laser; 4D; light; field

The principal investigator will develop a technique to determine the temperature distribution on a three-dimensional (3D) surface or object. The technique is similar to 3D photography, with the added and much more complicated challenge in mapping out the temperature. A camera with an array of micro-sized lenses will be aimed at the object. Because at different angles these lenses project the images, the effect of three dimensions is achieved. At the same time the intensities of the light reflected from various points of the surface is related to temperatures, the temperature on the 3D surface can be determined. The PI will also involve high school teachers, especially those from schools with high minority population, in addition to supervising graduate and undergraduate students.The proposed study will create a microlens array (MLA) for thermal imaging, numerical algorithms to extract thermal information, and determination of transient 3D temperature profiles of LED packages during operating conditions and in transient state. The author will apply an approach known as 4D light field imaging, which enables imaging of 3D surfaces by the array of lenses, each having a different perspective on the object, to project images of the target (i.e., plenoptic images) onto a CCD sensor. The 3D image of the surfaces can then be reconstructed from the multiple perspectives, using an algorithm previously developed by the PI. Based on the temperature-dependent reflectivity and the reflected light intensity of the surfaces (i.e., their thermoreflectance), temperature changes can be identified. The proposed technique can achieve high accuracy (~ 10 mK), high spatial resolutions (~ half of light wavelength; i.e. diffraction-limited), and nano-second temporal resolutions. The technique can therefore be used for steady, quasi-steady, and transient state thermal imaging, enabling a wide range of applications including extreme conditions, light emitting diodes (LEDs) and laser diodes (LDs).

首席研究员将开发一种技术来确定三维 (3D) 表面或物体上的温度分布。 该技术类似于 3D 摄影，但在绘制温度方面增加了更复杂的挑战。 带有微型镜头阵列的相机将瞄准该物体。由于这些镜头以不同的角度投射图像，因此实现了三维效果。 同时表面各点反射的光强度与温度有关，可以确定3D表面的温度。 除了指导研究生和本科生外，PI 还将涉及高中教师，特别是来自少数族裔人口较多学校的教师。拟议的研究将创建用于热成像的微透镜阵列 (MLA)、提取热信息的数值算法以及确定 LED 封装在工作条件和瞬态状态下的瞬态 3D 温度分布。 作者将应用一种称为 4D 光场成像的方法，该方法能够通过透镜阵列对 3D 表面进行成像，每个透镜对物体都有不同的视角，从而将目标图像（即全光图像）投影到 CCD 传感器上。然后可以使用 PI 先前开发的算法从多个角度重建表面的 3D 图像。 根据与温度相关的反射率和表面的反射光强度（即它们的热反射率），可以识别温度变化。 所提出的技术可以实现高精度（~ 10 mK）、高空间分辨率（~光波长的一半；即衍射极限）和纳秒级时间分辨率。因此，该技术可用于稳态、准稳态和瞬态热成像，从而实现广泛的应用，包括极端条件、发光二极管 (LED) 和激光二极管 (LD)。