| 摘要 |
<p>The apparatus comprises a receptacle for holding a quantity of reference material having known variation of refractive index with changes in the test parameter (which may be temperature, pressure or the like); an elongate optical waveguide in contact with the reference material which is itself in thermal contact (in the case of temperature measurement) or under the same pressure (in the case of pressure measurement); and means for measuring the transmission of light passed along the optical waveguide, so as to provide a measurement depending on the value of the parameter of the reference material and thus of the test material.</p> |
