Sensor and device for the measurement of radiant energy, in particular the energy associated with radio-frequency, microwave and light radiation signals

摘要

The sensor provides a termination for the guide along which the signal is propagated, which termination is capable of completely absorbing the incident energy and converting it into heat. The termination is in thermal contact with a monocrystal or with a layer of crystals, for example of ruby (oxide of aluminium), which is capable of being illuminated by one or more sources of light with a predetermined and sinusoidally modulated wavelength, in order to emit fluorescent radiation at a second wavelength, the phase displacement of which with regard to the modulating phase is a function of the temperature of the termination, and thus a function of the incident energy.PP For radio- frequency and microwave measurements, the termination terminates the coaxial cable or the waveguide with the characteristic impedance and comprises a layer of metal deposited on the monocrystal or on the layer of ruby crystals.PPIn the case of measurements of optical power, the termination is constituted by a black body which the input optical fiber abuts, the black body being in a thermal exchange relationship with the monocrystal or with the layer of ruby crystals.