On-line fiber bragg grating dithering

A method for determining a property, the method comprising:

• disposing an optical fiber comprising a series of fiber Bragg gratings at a location of the property, each fiber Bragg grating in the series being characterized by a light reflection frequency at which the fiber Bragg grating reflects light, wherein:
• the light reflection frequency for each fiber Bragg grating is different from the light reflection frequency of each adjacent fiber Bragg grating to minimize resonance of light between at least two of the fiber Bragg gratings in the series, at least two fiber Bragg gratings in the series have light reflection frequencies that overlap, and a change in the light reflection frequency of each fiber Bragg grating in the series is related to the property at the location of the each fiber Bragg grating;
• determining a change in the light reflection frequency for at least one of the fiber Bragg gratings in the series resulting from a measurement of the property;
• and
• relating the change to the property.

A method for producing a sensor for sensing a property, the method comprising:

• drawing an optical fiber sensitive to ultraviolet light;
• changing an angle of a phase mask with respect to the optical fiber;
• and
• illuminating the optical fiber with ultraviolet light through the phase mask to produce a series of fiber Bragg gratings;
• wherein:
• the light reflection frequency for each fiber Bragg grating is different from the light reflection frequency of each adjacent fiber Bragg grating to minimize resonance of light between at least two of the fiber Bragg gratings in the series, each fiber Bragg grating in the series being characterized by a light reflection frequency at which the fiber Bragg grating reflects light;
• at least two fiber Bragg gratings in the series have light reflection frequencies that overlap;
• and
• a change in the light reflection frequency of each fiber Bragg grating in the series is related to the property at the location of the each fiber Bragg grating.