title: Optical fiber specklegram sensor analysis by speckle pattern division.
abstract: An optical fiber specklegram sensor interrogation method based on speckle pattern fragmentation is presented. The acquired specklegram images are divided in a square grid, creating sub-images that are further processed by a correlation technique, allowing the quantification of localized changes in the specklegrams. The methodology was tested on the assessment of linear displacements using a microbending transducer, by evaluating different grid sizes. For a 5×5 grid, a 2.53  mm-1sensitivity over a 0.27 mm range was obtained, representing an extension of 237.5% in comparison to the standard interrogation technique. Therefore, the presented technique allows enhancing the sensor dynamic range without modifying the experimental setup.
authors.forename: Eric
authors.initials: E
authors.lastname: Fujiwara
authors.forename: Murilo Ferreira
authors.initials: MF
authors.lastname: Marques Dos Santos
authors.forename: Carlos Kenichi
authors.initials: CK
authors.lastname: Suzuki