초록

A method and apparatus for measuring the temperature and strain within a structure consists in having optical fibres incorporated in the structure, passing pulses of light down the fibre and detecting the backscattered light.

대표청구항 ▼

1. Apparatus for simultaneous measurement of temperature and strain distributions, which apparatus comprises a light source for generating pulses of light, a sensing network which comprises at least one optical fibre down which can pass pulses of light generated by the light source, a conversion mea

1. Apparatus for simultaneous measurement of temperature and strain distributions, which apparatus comprises a light source for generating pulses of light, a sensing network which comprises at least one optical fibre down which can pass pulses of light generated by the light source, a conversion means adapted to convert physical parameters into changes of strain or temperature along the sensing optical fibre thereby modifying the spectral response of the backscattered light passing back down the optical fibre as Brillouin backscatter and Rayleigh backscatter signals, a reference section of optical fibre subjected to known magnitude of the physical parameters, a receiver means in which a portion of returned light is passed on to a scanning optical filter able to resolve the Rayleigh peaks and Brillouin peaks and in which the optical signals are converted to electrical signals which are then fed into a processor means; the scan rate of the scanning optical filter being slower than the repetition rate of the optical pulses, allowing the spectral light of the backscattered light to be recorded along the length of the optical fibre and both the amplitude and frequency shift of the Brillouin peaks relative to the Rayleigh peaks able to be accurately measured from which measurements temperature and strain distributions along the same length of optical fibre can be determined.