摘要 |
<p>Apparatus for measuring two physical parameters, which apparatus comprises sensing means (6), modulation means (2) for varying the modulation frequency of the intensity of a source of light (1), means for conveying the light source (1) to an from the sensing means (6), and detection means for detecting the intensity of the light from the sensing means as a function of the modulation frequency, the sensing means being such that the amplitude and phase of the modulation of the light traversing the sensing means are determined by the modulation frequency as well as by the physical parameters to be measured, and where the phase is substantially affected by one parameter, preferably temperature, and the amplitude is substantially affected by the other parameter, preferably pressure.</p> |