Virginia Tech
Versatile and Sensitive Optical Sensing and Imaging with Spectral Interferometry
Abstract
dc:description.abstractgeneralOptical interferometry treats light as a wave. Light has not only brightness information, but also phase information, representing the number of cycles traveled, like hands on a clock. This phase information describes how far a beam of light travels in one path relative to another. Splitting light into two paths, passing one onto or through a sample, and re-combining the two beams turns this path length difference into a brightness difference, which can be measured by a camera, known as interferometry. Spectral interferometry measures this process for many optical wavelengths, or colors, simultaneously. The different colors measure the optical path difference more accurately and sensitively than one wavelength alone. Any change in the length of one path induced by vibration, temperature change, dissolution of a surface, or electrical voltage can be measured. Optical interferometry, or the act of combining two waves of light, can then be used as a very precise thermometer, voltmeter, or surface profiler. In this dissertation, spectral interferometry was used to measure the surface change of metals as they corrode in acidic environments, to see through all layers of biological tissues while they were mechanically stretched, and to probe and image microscopic mechanical sensors while they vibrate. This dissertation also describes calibration and estimation algorithms for spectral interference, or computer procedures that extract the most information from the camera for a measured signal.
Degree
thesis:*- Name thesis:degree_name
- Doctor of Philosophy
- Level thesis:degree_level
- doctoral
- Discipline thesis:degree_discipline
- Electrical Engineering
- Department dc:contributor.department
- Electrical Engineering
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 2025
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Thomas, Joseph Gabriel
- Chair dc:contributor.committeechair
-
- Zhu, Yizheng
- Committee members dc:contributor.committeemember
-
- Poon, Ting Chung
- Robinson, Hans
- Abbott, Amos L.
- Zhou, Wei
- Shao, Linbo
Subjects
dc:subject × 4Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
- Language dc:language.iso
- en
Identifiers
dc:identifier.*- Dc Identifier Other
- vt_gsexam:45162
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/140543