Infrared yog ib qho ntawm ntau qhov pom tsis pom nyob hauv lub hnub rays. Nws tau tshawb pom los ntawm tus kws tshawb fawb Askiv Herschel hauv 18{{2}0. Nws tseem hu ua infrared thermal tawg thiab muaj zog thermal nyhuv. Nws decomposed tshav ntuj nrog ib tug prism, thiab muab tso rau tus pas ntsuas kub ntawm cov ribbons ntawm ntau yam xim, sim ntsuas qhov cua sov nyhuv ntawm lub teeb ntawm ntau yam xim. Nws tau pom tias tus pas ntsuas kub sab nraum lub teeb liab ua kom sov siab tshaj plaws. Yog li ntawd, nws tau xaus lus tias nyob rau hauv lub hnub ci spectrum, yuav tsum muaj lub teeb pom kev sab nraum lub teeb liab, uas yog lub teeb infrared. Nws kuj tseem siv tau los ua qhov nruab nrab ntawm kev sib kis. Infrared lub npe lus Askiv yog Infrared, uas infrared txhais tau tias "hauv qab, hauv qab ...". Qhov zaus ntawm infrared rays ntawm lub hnub ci spectrum yog qis dua qhov pom lub teeb, nrog qhov zaus ntawm 0.3THz txog 400THz, sib xws rau lub wavelength ntawm 1000μm txog 0.75μm hauv lub tshuab nqus tsev.
Infrared tuaj yeem muab faib ua peb ntu, uas yog ze-infrared (high-frequency infrared, siab zog), lub wavelength nyob nruab nrab ntawm (3 ~ 2.5) μm ~ (1 ~ 0.75) μm; mid-infrared (intermediate zaus infrared, nruab nrab lub zog), lub wavelength yog (40 ~ 25)μm-(3 ~ 2.5)μm; deb infrared (tsawg zaus infrared rays, tsis tshua muaj zog), lub wavelength nyob nruab nrab ntawm 1500μm-(40 ~ 25)μm. Infrared (tshwj xeeb tshaj yog nyob deb-infrared) muaj cov nyhuv thermal, nws tuaj yeem cuam tshuam nrog feem ntau inorganic molecules thiab organic macromolecules hauv lub cev, kom cov molecules txav nrawm dua thiab rub tawm rau ib leeg, yog li tsim hluav taws xob, yog li infrared tuaj yeem siv rau cua sov. , kuj Nws tuaj yeem siv rau hauv kev tshawb fawb molecular spectroscopy. Far-infrared rays, tseem hu ua "terahertz rays" los yog "terahertz light" nyob rau hauv kev tshawb fawb tshawb fawb, nyob ib sab ntawm lub microwave zaus band thiab muaj ob lub zog ntawm infrared thiab microwaves. Lawv tau txais kev saib xyuas ntau hauv kev tshawb fawb thiab tau siv dav hauv biology, chemistry, thiab molecular spectroscopy. hauv kev tshawb fawb thiab organic synthesis.