FIBER-OPTIC INTERFEROMETRIC CHEMICAL SENSOR

摘要

FIBER-OPTIC INTERFEROMETRIC CHEMICAL SENSOR Al fiber-optic interferometric chemical sensor for detecting chemical vapors in the air. The chemical sensor 10 includes a light source 12 which outputs an optical signal to a first beam splitter 14. The first beam splitter 14 splits the optical signal into first and second components and transfers the optical signal over sensor and reference optical fibers 20 and 22 respectively. The optical fibers 20 and 22 are bonded to the sensor and reference magnetostrictive substrates 24 and 26, which oscillate in response to an oscillating electromagnetic field generated by a coil 28 circumscribing the substrates 24 and 26. The sensor substrate 24 is further coated with a substance to facilitate collection thereon of molecules associated with the chemical vapor being detected. The optical outputs of the optical fibers bonded to the substrates 24 and 26 are then output to second and third beam splitters 16 and 18 respectively, and first and second beam combiners 32 and 34 respectively. The beam splitters 16 and 18 and beam combiners 32 and 34 operate cooperatively to provide an interferogram which is output to a signal processing circuit 44. The signal processing circuit provides an electrical signal indicative of the collection on sensor substrate 24 of molecules of the chemical vapor being detected, and outputs the signal to a display system 46.