Development of Coherent Gradient-Sensing Tomographic Interferometer: Application to 3D Transient Temperature, Concentration, and Refractive Index Measurement

CTS-0079494 Jon P. Longtin纽约州立大学Stony BrookMRI：开发相干磁共振成像干涉仪：应用于三维瞬态温度、浓度和折射率测量摘要本项目将一种新的干涉测量技术--相干相干传感干涉测量技术（CGI）与多视图层析成像技术相结合，开发了一种用于瞬态、浓度和折射率测量的强大新工具。流体系统中温度、浓度或密度的三维（3D）测量。 CGI相对于传统干涉测量技术的独特优点包括：（1）对振动完全不敏感，（2）不需要参考光束，（3）连续可变的灵敏度，（4）较低的成本，（5）更可靠的操作。 这些功能使得基于CGI的仪器特别适合便携式和商业应用。 这种新型的仪器由一个CGI干涉仪组成，该干涉仪能够围绕透明的测试单元旋转以捕获不同角度的干涉图像，然后用于计算测试单元中流体-热系统的温度、浓度或密度等热物理性质的瞬态三维轮廓。密度对于理解和优化许多工程、生物和地球物理热流体系统是至关重要的。 例子包括先进的材料加工;自然和强制对流，和表面张力驱动的热传递;传质，和物种生产;和生物和生物工程现象。 这种测量需要验证计算机模拟的这种情况。CGI层析干涉仪的成功开发首次为流体热系统中的传输现象提供了直接、瞬态、3-D测量能力。 该仪器的一些直接应用将包括测量模拟晶体生长过程中的温度和浓度，测量激光诱导表面张力驱动流动过程中的温度，监测通过机械心脏瓣膜的流动中的示踪剂浓度，测量熔化和固化过程中的温度和浓度，以及评估透明固体中的三维裂纹结构。 目前还在开发一种便携式原型仪器，供其他实验室和当地公司评估和应用。 此外，仪器开发本身也是培养学生光学系统和图像处理能力的极好工具。

CTS-0079494Jon P. LongtinState University of New York Stony BrookMRI: Development of a Coherent Gradient-Sensing Tomographic Interferometer: Application to 3D Transient Temperature, Concentration, and Refractive Index Meas-urementAbstractThis project combines a novel interferometric measurement technique, Coherent Gradient-Sensing Interferometry (CGI), with multi-view tomography to develop a powerful new tool for transient, three-dimensional (3D) measurement of temperature, concentration, or density in fluid systems. The unique advantages of CGI over traditional interferometric techniques include: (1) complete insensitivity to vibration, (2) no reference-beam requirement, (3) continuously variable sensitivity, and (4) lower cost, and (5) more reliable operation. These features make a CGI-based instrument particularly well suited for portable and commercial applications. This novel instrument consists of a CGI interferometer capable of rotating around a transparent test cell to capture interferometric images at different angles, which are then used to compute transient, 3-D profiles of thermophysical properties such as temperature, concentration, or density for the fluid-thermal system in the test cell.Measurement of three-dimensional, time-varying profiles of temperature, concentration, and density is critical for the understanding and optimization of many engineering, biological, and geophysical thermal-fluid systems. Examples include advanced materials processing; natural and forced convection, and surface-tension-driven heat transfer; mass transfer, and species pro-duction; and biological and bio-engineering phenomena. Such measurements are needed to vali-date computer simulations of such situations. The successful development of the CGI Tomo-graphic Interferometer provides, for the first time, direct, transient, 3-D measurement capabilities for transport phenomena in fluid-thermal systems. Some immediate applications of the instru-ment will include measuring temperature and concentration during simulated crystal growth, measuring temperatures during laser-induced surface-tension-driven flows, monitoring tracer concentrations in flow through mechanical heart valves, measuring temperature and concentra-tion during melting and solidification, and assessing 3D crack structures in transparent solids. A prototype instrument is also being developed that will be portable and available for other labo-ratories and local companies for evaluation and application. Furthermore, the instrument devel-opment itself is an excellent vehicle for training students in optical systems and image process-ing.