Sensor for two-resonator refractometer

Feature of the open quasi-optical dielectric resonators is that they are always in direct contact with the environment, which is of their immediate part. Therefore, for the diagnosis of electro-physical parameters of the studied medium at the space point it is not necessary to ensure the forced air bleed to place into a resonator sensor. For example, suffice it to place a cylindrical dielectric resonator (CDR) at this point. Since the field of eigenmodes of quasi-optical CDR is specifically determined with the parameters of the studied medium and their variations lead to changes in the eigenfrequencies and Q-factor of the resonator. In addition, the temperature variation of the surrounding space entails a change in the geometric parameters of the resonator, which also leads to changes of its inherent spectral and energy characteristics. It is natural for solution of main refractometry problem the CDR should be used of a material with low linear expansion coefficient. In our researches, we have used easily accessible dielectric. It was a Teflon (with the real part of permittivity ε₁' = 2.04 and loss tangent tgδ₁ = 1.7×10^-4).