Development of a heterodyne interferometer for nanometer scale displacement measurement
Date
1997
Authors
Stibich, Aaron
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The following thesis discusses the development of a heterodyne interferometer for the purpose of nanometer scale displacement measurements. High resolution displacement transducers are employed in numerous applications, including vibration analysis, surface profiling, position control, tilt meters, and non-destructive quality evaluation of solid parts. The University of Victoria Institute for Robotics and Intelligent Systems (IRIS) research group has recently established a materials and mechatronics laboratory, creating a need for a high resolution displacement transducer. Design criteria for this device are subnanometer resolution, a sample rate of approximately 1 kHz, a dynamic range (measurement range / resolution) of 1x10₇ or more, and enough flexibility and robustness to take measurements in a variety of research projects . Research into the available technologies led to the conclusion that a heterodyne interferometer was the best candidate. This technique has a wide bandwidth, excellent dynamic range, and is highly resistant to noise. A heterodyne interferometer was successfully assembled and calibrated with 1 mm accuracy and sub-nanometer resolution.