Development of a miniature, multichannel, extended, range Fabry-Perot Fiber-Optic Laser Interferometer system for low frequency Si-traceable displacement measurement

摘要: Laser interferometry has become a staple of SI-traceable displacement measurement techniques. With decreasing cost per channel, miniaturization, and a multitude of commercially available off-the-shelf systems, these systems create ever more attractive applications unheard-of a few years ago. Although significant efforts have been made to shrink the size of the optical components necessary for a fully functioning laser interferometer sensor, most currently available commercial sensors have a sensing element on the order of millimeters or more [1].The goal of the work presented in this paper, which builds on our previous experience with fiber-based laser interferometer systems [2], was to build a directly SI-traceable laser interferometer displacement sensor with a sensor head no bigger than a single optical fiber diameter (0.125 mm). The sensor was designed and built specifically to serve as the primary displacement and force gauge sensor in an SI-traceable precision nanoindentation platform (PNP)[3]. Significant efforts were made to assure that each component not only performed a needed function, but also contained known uncertainties or a specific methodology to ascertain uncertainty values.