Patent ID: 6389187
Filing Date: 2002-05-14
Classification: G01D,G01M

Abstract:
A bend sensor comprising:a fibre assembly including a multicore optical fibre having component cores sufficiently separated to counteract crosstalk and a sensor length section; coupling means for coupling radiation propagating in a first core of said component cores into a second core of the component cores of the fibre assembly; reflecting means for reflecting a portion of incident radiation, said reflecting means and said coupling means arranged such as to define a first optical path corresponding to radiation propagating within said first core and a second optical path corresponding to radiation propagating within said second core, wherein said paths have an optical path difference over said sensor length section; and analysing means for analysing radiation output from the fibre assembly and developing and spectrally dispersing interferograms formed between the radiation propagating in the first and second optical paths and for providing a fibre curvature output determined from phase variations in said interferograms.