Abstract: A bolometer comprising an outer surface for the thermal absorption of incident radiation in thermal contact with a radiation measurement element having a variable resistance (R) depending on the temperature, the element being in a heat feedback loop comprising a corrector for applying a heating power to a resistive heating means in order to maintain the temperature of the resistor equal to a setpoint temperature (Tref). According to the invention, the resistive heating means comprises the element, the corrector is designed to generate a frequency component (S1) of the heating power, which is applied to a coupling means provided between the element and the corrector in order to apply a DC-free signal to the element, a coupling means, separate from the means, is provided between the element and a DC bias means in order to maintain the resistor at a prescribed continuous operation point.

Abstract: A bolometer comprising an outer surface for the thermal absorption of incident radiation in thermal contact with a radiation measurement element having a variable resistance (R) depending on the temperature, the element being in a heat feedback loop comprising a corrector for applying a heating power to a resistive heating means in order to maintain the temperature of the resistor equal to a setpoint temperature (Tref). According to the invention, the resistive heating means comprises the element, the corrector is designed to generate a frequency component (S1) of the heating power, which is applied to a coupling means provided between the element and the corrector in order to apply a DC-free signal to the element, a coupling means, separate from the means, is provided between the element and a DC bias means in order to maintain the resistor at a prescribed continuous operation point.

Abstract: Process for the digitization and linearization of a quasi-sinusoidal periodic characteristic transducer and the corresponding apparatus.The process consist of measuring a variation (.DELTA..phi..sub.x) of a signal (.phi..sub.x) received by the transducer in accordance with the following operations:superimposing on the signal to be measured a first auxiliary periodic signal (.phi..sub.I) of frequency F.sub.I higher than the highest frequency of the range of the signal to be measured and of amplitude substantially equal to .phi..sub.o /2 and a second auxiliary signal constituted by a periodic linear ramp (.phi..sub.R) of a frequency f.sub.R well below F.sub.I and of amplitude .phi..sub.1, the transducer thus receiving a composite signal constituted by the signal to be measured, the first auxiliary signal and the second auxiliary signal;deducing from the signal supplied by the transducer, two periodic signal V.sub.C1 and V.sub.C2, of period .phi..sub.

Abstract: A superconducting magnetometer, using a superconducting compound at the temperature of liquid nitrogen, is disclosed. It consists in the use, as a sensitive element, of a piece of superconducting material with a central constriction enabling the demarcation of a channel in which the number of useful, intrinsic loops is sufficiently limited for the sensitive element to behave like a DC SQUID with a single loop.