Structural microfiber long-period gratings

Long Period Fibre Gratings

Highly Sensitive Refractive Index Sensor Based on Adiabatically Tapered Microfiber Long Period Gratings

We demonstrate a refractive index sensor based on a long period grating (LPG) inscribed in a special photosensitive microfiber with double-clad profile. The fiber is tapered gradually enough to ensure the adiabaticity of the fiber taper. In other words, the resulting insertion loss is sufficiently small. The boron and germanium co-doped inner cladding makes it suitable for inscribing gratings i...

Long-period gratings in wavelength-scale microfibers.

We report the fabrication of long-period gratings (LPGs) in wavelength-scale microfibers with diameters from 1.5 to 3 microm. The LPGs were fabricated by use of a femtosecond IR laser to periodically modify the surface of the fibers. These LPGs have grating periods of a few tens of micrometers, much smaller than those in conventional optical fibers. A compact 10-period LPG with a device length ...

Multiplexed long period gratings with differential interrogation

TEMPERATURE CHARACTERISATION OF LONG PERIOD GRATINGS for SENSOR APPLICATIONS

Long period grating proposed as a sensor display sensitivity to ambient temperature variations. Therefore full temperature characterisation is essential. In this paper the temperature effects on the spectral profiles of two sets of long period gratings (LPGs) of different periods are investigated. The results obtained show that the shorter period LPGs were found to be less sensitive than the lo...