METHOD OF DISPLACEMENT MEASUREMENT Russian patent published in 1998 - IPC

FIELD: fiber optics transmission systems in measuring equipment, applicable for measurement of object displacements. SUBSTANCE: modulated radiation at frequency ω₁ applied to the zone of measurements is modulated at frequency ω₁ which is lower than ω₂, with ω₁≫ ω₂. The first harmonic signal of modulation frequency ω₁ is discriminated. Then signals of the first and second harmonics are applied to the comparison unit, where they are compared. The comparison unit output signal is applied to the input of comparator, where it is compared with reference voltage. The comparator output signal is applied to the control input of the access and storage unit, which receives also modulating signal at frequency ω₂, and the measurand of mutual displacement of the end of fiber optics is determined according to the output signal of the access and storage unit. EFFECT: eliminated multiplicative noise, enhanced accuracy of measurements. 5 dwg