Publications

Publications by José Luís Santos

2002

Micromachined low-finesse Fabry-Pérot interferometer for the measurement of low DC electrical currents

Authors
Heredeor, RL; Santos, JL; De Caleya, RF; Araújo, FM; Ferreira, LA; Guerrero, H;

Publication
2002 15th Optical Fiber Sensors Conference Technical Digest, OFS 2002

Abstract
An optical fiber current sensor based on a permanent magnet fixed on the center of a micromachined Si membrane has been presented. The transducing operation principle is magneto-mechanical and has a linear response. A great improvement of the sensitivity of the microcavities was achieved by the use of a planar coil. Interrogation of the transducer has been carried out using a Fabry-Perot interferometer with an all-fiber detection system to avoid the influence of electromagnetic noise. The effectiveness of a fiber scheme based on the utilization of two fibre Bragg gratings to generate two quadrature phase-shifted interferometric signals has also been reported. © 2002 IEEE.

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1990

Electronic speckle-pattern interferometry using single-mode fibers and active fringe stabilization

Authors
Santos, JL; Newson, TP; Jackson, DA;

Publication
Optics Letters

Abstract
Optical fibers are used to provide object and reference illumination in the context of the electronic speckle-pattern interferometry technique. An all-fiber Michelson interferometer is used, with an electronic servo and a piezoelectric phase modulator, to obtain compensation for environmentally induced phase coupling into the fiber arms. © 1990 Optical Society of America.

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2008

Recent Advances on Optical Sensing Using Photonic Crystal Fibers

Authors
Marques, MB; Magalha~es, F; Carvalho, JP; Fraza~o, O; Arau´jo, FM; Santos, JL; Ferreira, LA; Cordeiro, CMB; de Matos, CJS;

Publication
1ST WORKSHOP ON SPECIALTY OPTICAL FIBERS AND THEIR APPLICATIONS

Abstract
The application of hollow-core photonic crystal fibers for gas sensing is reviewed and discussed. Some problems with splicing to standard fibers and gas diffusion into the core are addressed. Current work at INESC Porto in the development of sensing heads and interrogation units is also reported.

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2004

<title>Simultaneous measurement of temperature and strain using a step spectrum profile fibre Bragg grating arrangement</title>

Authors
Frazao, O; Romero, R; Araujo, FM; Ferreira, LA; Santos, JL;

Publication
Second European Workshop on Optical Fibre Sensors

Abstract

2005

<title>Strain and temperature discrimination using a Hi-Bi grating partially exposed to chemical etching</title>

Authors
Frazao, O; Pereira, DA; Santos, JL; Araujo, FM; Ferreira, LA;

Publication
17th International Conference on Optical Fibre Sensors

Abstract

2007

<title>Modal interferometer based on a single non-adiabatic fibre taper</title>

Authors
Frazão, O; Caldas, P; Santos, JL; Araújo, FM; Ferreira, LA;

Publication
Third European Workshop on Optical Fibre Sensors

Abstract