InfraTec has introcuced the LIM-253 pyroelectric detector in a compact TO39 package, which offers three spectral channels for gas analysis.
NDIR gas analysers frequently work by a comparison method, where the test gas channel signal depending on the concentration of gas is compared to the reference channel. Dual channel detectors like the LIM-252 can be used in this way to measure the concentration of one gas. However, it is quite often the case that two gases need to be measured at the same time. This would mean either using more than one detector and an external beam divider or using a detector with a larger TO8 (14 mm diameter) housing.
InfraTec has introduced the thermally compensated three channel detector LIM-253 as the first of a new family of very compact multi element detectors in TO39 and TO18 bodies. As with all detectors from InfraTec lithium tantalate (LiTaO3) is used as the pyroelectric element, which guarantees a very low temperature coefficient of the detectors signal output. The three active and the three thermal compensation elements are made from 25µm thick LiTaO3 and each has a squared area of 1.3 mm. Additionally, within the detector housing are three JFET impedance converters are connected for voltage mode. InfraTec’s standard NBP filters for detection of CO2, CH4, CO, HC and NOX as well as the reference filter are available.