Period Dependent Temperature and Ambient Index Effects on Long Period Fibre Gratings
نویسندگان
چکیده
The ambient index and temperature effects on the spectral profiles of two sets of long period gratings (LPGs) of different periods were investigated. The shorter period LPGs were found to be more sensitive than the longer period LPGs over identical ambient index ranges but less sensitive over identical temperature ranges. The coupling wavelength shifts due to temperature are also seen to be linear and in opposite directions in each set of LPGs and unlike the ambient index shifts there seems to be no obvious modal dependency with respect to sensitivity in any individual LPG. The conclusion to this investigation is that it may be possible to design an LPG of such a period that parts of the spectral profile are unaffected by temperature whilst maintaining a reasonable ambient index sensitivity.
منابع مشابه
A Review of Refractometric Sensors Based on Long Period Fibre Gratings
In the last decade refractometric sensors have attracted an increasing interest by the scientific community due to their ability to perform ambient monitoring, to assess food quality and safety, and also to the fact that they enable the development of label free sensors in the biomedical area. These advances result, namely, from the use of long period fibre gratings in the turning points and/or...
متن کاملRespiratory monitoring using fibre long period grating sensors
ABSTRACT We demonstrate the use of a series of in-line fibre long period grating curvature sensors on a garment, used to monitor the thoracic and abdominal volumetric tidal movements of a human subject. These results are used to obtain volumetric tidal changes of the human torso showing reasonable agreement with a spirometer used simultaneously to record the volume at the mouth during breathing...
متن کاملOptical fibre long-period grating sensors: characteristics and application
Recent research on fibre optic long-period gratings (LPGs) is reviewed with emphasis placed upon the characteristics of LPGs that make them attractive for applications in sensing strain, temperature, bend radius and external index of refraction. The prospect of the development of multi-parameter sensors, capable of simultaneously monitoring a number of these measurands will be discussed.
متن کاملTEMPERATURE 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...
متن کاملUltrahigh-Temperature Regeneration of Long Period Gratings (LPGs) in Boron-Codoped Germanosilicate Optical Fibre
The regeneration of UV-written long period gratings (LPG) in boron-codoped germanosilicate "W" fibre is demonstrated and studied. They survive temperatures over 1000 °C. Compared with regenerated FBGs fabricated in the same type of fibre, the evolution curves of LPGs during regeneration and post-annealing reveal even more detail of glass relaxation. Piece-wise temperature dependence is observed...
متن کامل