| 摘要 |
<p>PURPOSE:To improve total accuracy without narrowing light pulse width by preventing solution from diverging due to influence of noise during inverse transformation. CONSTITUTION:Each time Fresnel reflection light is emitted from an optical fiber 1, the light is converted into photocurrent while being led by a photo diode 11 via an optical filter 8 and a light switch 9, and an average output is supplied through a photocurrent amplifying circuit 12 and a digital averager circuit 13 to a control storage calculation circuit 14 and stored in it. The control storage calculation circuit 14 stores a number of times wherein waveforms become linear as an optimum number of repetitions while repeating deconvolution with respect to a stored average output. When temperature is measured, deconvolution is repeated by the number of repetitions with respect to waveform data of two kinds of Raman scattering light to calculate a temperature distribution along the optical fiber.</p> |
