Technique of FBG fabrication with an arbitrary spectrum

An arbitrary FBG spectrum can be obtained as the addition of the contribution of some concatenated subFBGs written without phase jump using the same phase mask. An adaptive filter is used in order to obtain, from the desired spectrum, the parameters of the different subFBGs reproducing the required response

Tunable fiber laser using concatenated non-adiabatic single-mode fiber tapers

An erbium doped fiber ring laser (EDFRL) that incorporates four non-adiabatic concatenated single-mode fiber tapers (acting as tunable filter in the laser cavity) is presented. These concatenated fiber tapers integrates a filter with a narrower band-pass and a higher modulation depth than a single taper. The tuning of this filter was implemented applying a controlled perturbation in the fiber taper. The proposed laser architecture was successfully demonstrated in the laboratory in which a tuning range of 20.8nm (1544.5nm-1565.3nm) were measured

Red de difracción optimizada para aplicaciones en redes de interferómetros Fabry-Perot

In order to obtain an acoustic waves sensor network a lot of interferometer transducers must be multiplexed. The use of Fibre Bragg Grating (FBG)- based interferometer allows the applications of Wavelength Division Multiplexing (WDM) technology and multiplex large number of transducers in the sensor system. The sensing system uses Amplified Spontaneous Emission (ASE) source for interrogating arrays of FBG sensors The Coherence Multiplexed (CM) system interrogated with ASE source do not suffer from phase induced intensity noise due to their coherent features. In this paper, an optimum FBG for FBG-Based interferometer interrogated by a FBG-based Narrow ASE source is designed, developed and characterised

Mode width sensitivity with strain in index guided Photonic Crystal Fibres

RESUMEN: Se estudia el comportamiento de la anchura del modo fundamental en una Fibra de Cristal Fotónico (FCF) guiada por índice cuando se aplica un estiramiento en un rango de valores comprendido entre 0.5 y 2.5%ε. Se identifican las regiones de frecuencia normalizada (Λ/λ) y de la fracción de llenado de aire d/Λ en los que se observa la máxima influencia del estiramiento en la sensibilidad. Finalmente, se analiza y discute su evolución.ABSTRACT: The fundamental mode width behaviour is studied for an index guided Photonic Crystal Fibre (PCF) when strain is applied in a range of values between 0.5 and 2.5%ε. The regions of normalized frequency (Λ/λ) and of the filling air fraction d/Λ, in which maximum strain influence is observed, are identified. Finally, its evolution is analyzed and argued

Control del periodo espectral de interferencias en tapers de fibras monomodo

A really simple study of the theoretical aspect of the filters based on non adiabatic tapers in single-mode fibers is presented. It concludes on the possibility to vary the period of the spectral interferences through the variation of the taper diameter. The taper diameter is varied thanks to the stretching of the fiber while it is heated with a movable oxy-butane flame. Some measurements had been done on different tapers built with the same fabrication parameters in order to make the characteristic curve of the period evolution during the fabrication. Then this characteristic is used in order to make tapers with an expected spectral period

Fiber ring laser using non-adiabatic single-mode fiber tapers as a tunable filter

RESUMEN: Un láser en anillo de fibra dopada con erbio (LAFDE) con fibras monomodo estrechadas no adiabáticas concatenadas, actuando como filtro sintonizable dentro de la cavidad, es presentado en este artículo. Estas fibras monomodo estrechadas no adiabáticas concatenadas presentan un ancho de banda más estrecho y una profundidad de modulación mayor que un sola fibra estrechada. La sintonización de este filtro óptico se llevó a cabo aplicando una perturbación controlada en las fibras estrechadas. El funcionamiento de este láser se demostró experimentalmente en el laboratorio, obteniendo un rango de sintonización de 20.8nm (1544.5nm-1565.3nm).ABSTRACT: An erbium doped fiber ring laser (EDFRL) that incorporates four non-adiabatic concatenated single-mode fiber tapers (acting as tunable filter in the laser cavity) is presented. These concatenated fiber tapers integrates a filter with a narrower band-pass and a higher modulation depth than a single taper. The tuning of this filter was implemented applying a controlled perturbation in the fiber taper. The proposed laser architecture was successfully demonstrated in the laboratory in which a tuning range of 20.8nm (1544.5nm- 1565.3nm) were measured