Title :
A laser-interferometer measuring displacement with nanometer resolution
Author :
Zagar, Bernhard G.
Author_Institution :
Inst. for General Electr. Eng. & Electr. Meas., Tech. Univ. Graz, Austria
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. The author 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. Some experimental data for crack-tip opening displacement measurements on micro cracks and the measurement of thermal dilatation coefficients of copper are given
Keywords :
CCD image sensors; crack detection; displacement measurement; image processing; light interferometers; strain measurement; thermal expansion measurement; thermal variables measurement; Cu; crack-tip; digital signal processing; laser-interferometer; material science; micro cracks; nanometer resolution; opening displacement measurements; strain measurement; strain sensor; thermal dilatation 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;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 1993. IMTC/93. Conference Record., IEEE
Conference_Location :
Irvine, CA
Print_ISBN :
0-7803-1229-5
DOI :
10.1109/IMTC.1993.382608
