| 摘要 |
An interferometric measurement device includes a broad-spectrum spontaneous emission light source; a measurement interferometer, receiving as input a light signal with input light power and delivering as output a modulated light signal with output light power, the modulated light signal being modulated at a modulation frequency, depending on a physical parameter (&OHgr;R) to be measured and being proportional to the input light power; an optical radiation detector, receiving the modulated light signal exiting from the measurement interferometer and delivering a modulated electrical signal representative of the output light power; a filtering interferometer, insensitive to the physical parameter to be measured, having a free spectral range ISL and a finesse F selected such that an interval of frequencies, centred around an optimal frequency foptim equal to (2k+1) ISL/2, k being a natural number, and of width &Dgr;f equal to [0.9−(3/2F)] ISL, includes the modulation frequency of the modulated light. |
