Current detection type and thermocouple calibration method of the current detection type thermocouple

摘要

PROBLEM TO BE SOLVED: To provide a calibration method of a current detection type thermocouple or the like permitting easy and accurate temperature calibration and correction, even if a hot-junction or a cold-junction is formed on a cantilever or a diaphragm, and to provide a relevant current detection type thermocouple, a thermal-type infrared sensor, and an infrared detector.;SOLUTION: In order to calibrate a thermocouple, a calibrating thermocouple formed of the same thermocouple material as that of a detecting thermocouple is used to determine in advance the absolute thermoelectric power E_ro of the calibrating thermocouple. The detecting thermocouple is assumed to have the same E_ro as well. The internal resistance r_s of the detecting thermocouple is determined, and a short circuit current value I_s by a measured temperature difference ΔTs is measured by an operational amplifier to determine a measured temperature difference ΔTs. Offset calibration is also performed on the operational amplifier. A thermocouple and a switch are connected to the inverting input terminal of the operational amplifier to enable also sensor selection. These are connected to a non-inverting input terminal, and an equivalent current detection type thermocouple having a small resistance r connected to the inverting input terminal is used to enable switching between a plurality of thermocouples.;COPYRIGHT: (C)2008,JPO&INPIT