| 摘要 |
<p>The invention relates to a photopyroelectric measuring device and installation intended to evaluate and monitor the thermal properties of condensed substances. According to the invention, the device comprises a LED (), a luminous intensity sensor (), a temperature sensor () which are mounted at one end of an opaque thermally-insulating tube () and a pyroelectric sensor () mounted at the opposite end of the same opaque tube () so that the LED () irradiates with harmonically modulated radiation the upper side of the composite pyroelectric sensor () which emits a signal depending on the thermal and geometrical properties of adjacent layers, the luminous intensity sensor () receives a part of the retroreflected electromagnetic radiation, while the temperature sensor () allows the continuous component of the temperature inside the tube () to be measured. The measuring installation, as claimed by the invention, comprises the photopyroelectric device and a central control unit which delivers two signals to a circuit () for conditioning the excitation signal, which synthesizes the control signal of a current source () so as to allow operations of verification and calibration of the measuring installation to be carried on while conditioning the signal from the pyroelectric sensor () allowing the measurement of the signals delivered by the luminous intensity sensor () and temperature sensor (), permitting the acquisition of the processed components of the pyroelectric signal and the acquisition of only the conditioned signal emitted by the pyroelectric sensor ().</p> |
