Efficient temperature and strain discrimination with a single type I fiber Bragg grating transducer

Writing a single fibre Bragg grating (FBG) with a proper non-sinusoidal axial in-core index increment profile, the highly desirable simultaneous measurement of temperature and strain using an FBG transducer can be efficiently reached. The optimised UV energy that equalize the first and second harmonics on a hydrogenated standard telecommunication fiber is demonstrated. Using this approach, the number of in-line multiplexed transducers for typical optical source bandwidths is practically doubled