An IR filter makes all the difference. Thermal detectors are naturally polychromatic, and a filter is needed to detect specific gases/wavelengths.
Single wavelengths can only be detected if corresponding narrow-band filters are used because without the appropriate filter pyroelectric detectors would not even be able to detect a single gas.
The filters for pyroelectric detectors are not available individually but only in combination with our pyroelectric detectors on a standard basis. For purposes of development, however, we offer an optical gas and flame filter kit. This kit comprises 17 IR bandpass filters integrated in a socket for a TO-39 housing.
In the datasheet below, you will find the most current filters available for selection. If the appropriate filter for your application is not listed, please inquire with us.