In the last 4 years, experimental evidences about the potential use of optical sensors based on Lossy Mode Resonances (LMR) have been presented in the literature. These LMR sensors have some similarities with Surface ...

An optical fibre refractometer has been developed by etching and deposition of a thin film of indium tin oxide (ITO) on a single-mode-multimode-single-mode (SMS) fibre structure. The interference between modes in this ...

In this work, the monitoring of the etching process up to a diameter of 30 µm of two LPFG structures has been compared, one of them had initially 125 µm, whereas the second one had 80 µm. By tracking the wavelength shift ...

The diameter of long-period fiber gratings (LPFGs) fabricated in optical fibers with a low cutoff wavelength was be reduced by hydrofluoric acid etching, enhancing the sensitivity to refractive index by more than a factor ...

Two phenomena for enhancing the sensitivity of longperiod fiber gratings are combined toward an increase of the sensitivity to strain of this type of devices: the dispersion turning point (DTP) and the cladding diameter ...

The sensitivity of a liquid level sensor based on a single-mode-multimode-single-mode fiber structure has been increased by hydrofluoric acid etching. The etching process was analyzed and monitored both theoretical and ...

Two simple optical fibre structures that do not require the inscription of a grating, a cladding removed multimode optical fibre (CRMOF) and a single-mode multimode single-mode structure (SMS), are compared in terms of ...

A reflection configuration setup for long-period fiber gratings is presented. It permits to obtain a unique band with attenuation double than that obtained in transmission configuration, which is interesting for ...

This work presents a refractive index sensor based on a long period fiber grating (LPFG) made in a reduced cladding fiber whose low order cladding modes have the turning point at large wavelengths. The combination of ...

The incremental deposition of a thin overlay on the cladding of a long-period fiber grating (LPFG) induces important resonance wavelength shifts in the transmission spectrum. The phenomenon is proved theoretically with ...