Title :
A laser-interferometer measuring displacement with nanometer resolution
Author :
Zagar, Bemhard G.
Author_Institution :
Inst. of Gen. Electr. Eng. & Electr. Meas., Tech. Univ. of Graz, Austria
fDate :
4/1/1994 12:00:00 AM
Abstract :
In material science there are certain classes of problems that require strain measurement over base lengths as small as 100 μm and still demand a resolution limit of about 10 microstrains. This paper presents an interferometric strain sensor that is able to cope with that demand. The optical principle is given, and the digital signal processing involved is detailed. Furthermore, some experimental data for crack-tip opening displacement measurements on micro cracks and the measurement of thermal expansion coefficients of copper is given
Keywords :
copper; crack detection; displacement measurement; light interferometers; light interferometry; measurement by laser beam; strain measurement; thermal expansion measurement; 10 mum; CCD sensor; Cu; crack-tip opening displacement measurement; digital signal processing; interferometric strain sensor; laser-interferometer; material science; micro cracks; nanometer resolution; strain measurement; thermal expansion coefficients; Capacitive sensors; Digital signal processing; Displacement measurement; Laser theory; Materials science and technology; Optical interferometry; Optical sensors; Optical signal processing; Signal resolution; Strain measurement;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
