Development of fiber long period gratings for biologicalsensor applications

摘要

We present a fiber long period grating based sensor for biological applications. Inscribed by using point-by-point method, the LPG has a resonant wavelength close to the emission wavelength of biological objects of interest. The part of the light, emitted from sensing area, is collected by both fiber core and cladding, while the majority of light is coupled into the cladding. Back coupling of light of certain wavelength can selectively be achieved from fiber's cladding to core thanks to the LPG. Such selective back coupling allows the increase of efficiency of remote detection of biological objects of interest, using excitation source and detector on the same side of the fiber.