Optical displacement measurement with GaAs/AlGaAs-based monolithically integrated Michelson interferometers

Author

Hofstetter, Daniel ; Zappe, Hans P. ; Dändliker, René

Author_Institution

Paul Scherrer Inst., Zurich, Switzerland

Volume

15

Issue

4

fYear

1997

fDate

4/1/1997 12:00:00 AM

Firstpage

663

Lastpage

670

Abstract

Two monolithically integrated optical displacement sensors fabricated in the GaAs/AlGaAs material system are reported. These single-chip microsystems are configured as Michelson interferometers and comprise a distributed Bragg reflector (DBR) laser, photodetectors, phase shifters, and waveguide couplers. While the use of a single Michelson interferometer allows measurement of displacement magnitude only, a double Michelson interferometer with two interferometer signals in phase quadrature also permits determination of movement direction. In addition, through the use of two 90° phase-shifted interferometer signals in the latter device, a phase interpolation of 2π/20 is possible, leading to a displacement resolution in the range of 20 nm. The integration of these complex optical functions could be realized with a relatively simple fabrication process

Keywords

III-V semiconductors; Michelson interferometers; aluminium compounds; displacement measurement; distributed Bragg reflector lasers; gallium arsenide; integrated optics; optical couplers; optical sensors; phase shifters; photodetectors; 90° phase-shifted interferometer signals; GaAs-AlGaAs; GaAs/AlGaAs-based monolithically integrated Michelson interferometers; complex optical functions; displacement magnitude; displacement resolution; distributed Bragg reflector laser; double Michelson interferometer; movement direction; optical displacement measurement; optical displacement sensors; phase interpolation; phase quadrature; phase shifters; photodetectors; relatively simple fabrication process; single Michelson interferometer; single-chip microsystems; waveguide couplers; Displacement measurement; Distributed Bragg reflectors; Gallium arsenide; Integrated optics; Interferometers; Optical interferometry; Optical materials; Optical sensors; Optical waveguides; Sensor systems;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/50.566688

Filename

566688