Apparatus for characterizing fiber bragg gratings

An apparatus for characterizing at least one fiber Bragg grating, the apparatus comprising:

• a laser pulse source, the laser pulse source generating at least one input laser pulse;
• an optical spectrum analyzer;
• a first optical path optically coupled to the laser pulse source, the first optical path comprising a pulse stretcher and an attenuator, wherein a first portion of the input laser pulse propagates from the laser pulse source and is stretched by the pulse stretcher and is attenuated by the attenuator;
• a second optical path optically coupled to the first optical path and comprising a mirror, wherein a first portion of the stretched and attenuated laser pulse from the first optical path is reflected from the mirror;
• a third optical path optically coupled to the first optical path and comprising a first fiber Bragg grating, wherein a second portion of the stretched and attenuated laser pulse from the first optical path is reflected from the first fiber Bragg grating;
• a fourth optical path optically coupled to the second optical path, the third optical path, and the optical spectrum analyzer, wherein the reflected pulse from the mirror and the reflected pulse from the first fiber Bragg grating propagate to the optical spectrum analyzer;
• and
• a fifth optical path optically coupled to the laser pulse source and the optical spectrum analyzer, the fifth optical path comprising a delay line, wherein a second portion of the input laser pulse propagates from the laser pulse source along the fifth optical path to the optical spectrum analyzer.