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

Volume

43

Issue

2

fYear

1994

fDate

4/1/1994 12:00:00 AM

Firstpage

332

Lastpage

336

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;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/19.293440

Filename

293440