Gas refractometry based on an all-fiber spatial optical filter

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Susana Silva (Author) Other; Coelho, L (Author) FCUP; Andre, RM (Author) Other; Frazao, O (Author) FCUP

Journal

Title: Optics Letters

Vol. 37

Pages: 3450-3452

ISSN: 0146-9592

Publisher: Optical Society of America

Indexing

ISI Web of Knowledge - 10 Citations

Scopus - 10 Citations

Other information

Authenticus ID: P-002-6XQ

DOI: 10.1364/ol.37.003450

Abstract (EN): A spatial optical filter based on splice misalignment between optical fibers with different diameters is proposed for gas refractometry. The sensing head is formed by a 2 mm long optical fiber with 50 mu m diameter that is spliced with a strong misalignment between two single-mode fibers (SMF28) and interrogated in transmission. The misalignment causes a Fabry-Perot behavior along the reduced-size fiber and depending on the lead-out SMF28 position, it is possible to obtain different spectral responses, namely, bandpass or band-rejection filters. It is shown that the spatial filter device is highly sensitive to refractive index changes on a nitrogen environment by means of the gas pressure variation. A maximum sensitivity of -1390 nm/RIU for the bandpass filter was achieved. Both devices have shown similar temperature responses with an average sensitivity of 25.7 pm/degrees C. (C) 2012 Optical Society of America

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 3