Forming long period optical fibre gratings using a CO2 laser beam and microbending

摘要

Optical fibre 16, 23 is gripped at two points by a support structure 24 and the fibre is subjected to tensile strain between the two points and at an angle (in direction 23d) and at the same time a COSB2/SB laser emitted by laser system 11 is focussed to a predetermined width by a lens 13, 21 onto the area between the two gripping points. The fibre is moved at predetermined intervals to form grating 23a, 23b, 23c. A controller 15 controls the intensity of the CO2 laser beam, the focussing distance of the lens, and the tensile force applied by the optical fibre support.