Thaum cov pa tawm, nws absorbs ib pawg ntawm cov hluav taws xob infrared (gas infrared absorption yam ntxwv ncov). Vim qhov sib txawv ntawm cov yam ntxwv ntawm cov hluav taws xob infrared nruab nrab ntawm cov pa hluav taws xob thiab ib puag ncig ib puag ncig, qhov sib txawv no yuav tsim qhov sib txawv ntawm cov hluav taws xob hluav taws xob tseem ceeb nyob rau hauv kev tshawb pom ntawm infrared thermal imager. Lub infrared thermal imager siv lub hauv paus ntsiab lus no kom raug txheeb xyuas cov pa xau thiab nws qhov chaw los ntawm kev ntes thiab tshuaj xyuas qhov sib txawv ntawm cov hluav taws xob infrared.
Infrared thermal imagers feem ntau yog nruab nrog xaiv qhov nqaim qhov rais tsim (filters) hauv kev tshawb nrhiav roj, uas tuaj yeem ntes thiab duab cov infrared nqus cov yam ntxwv siab ntawm cov roj tshwj xeeb. Piv txwv li, rau kev tshawb pom ntawm cov organic tebchaw tsis muaj zog (VOCs), cov kab lus teb tau teeb tsa ntawm 3.2-3.4 μ m.
Tom qab cov duab lim dej thiab cov roj ua kom zoo dua cov duab algorithm ua tiav, cov pa xau tuaj yeem tshwm sim hauv lub sijhawm tiag tiag thiab intuitively los ntawm cov duab thermal.
