Cesium iodide (CsI) scintillators are categorized into thallium-doped CsI(Tl), sodium-doped CsI(Na), and pure CsI. Among these, thallium-activated cesium iodide crystals (CsI(Tl)) are non-hygroscopic in air and can be easily processed into thin sheets, making them widely applicable for energy spectrum detection. Sodium-doped cesium iodide crystals (CsI(Na)), though hygroscopic and requiring sealed packaging, exhibit a shorter decay time of 630 ns and an emission peak at 420 nm, which aligns well with the sensitive wavelength range of photomultiplier tubes equipped with bialkali photocathodes. Similar to CsI(Tl), CsI(Na) crystals possess high density and a large effective atomic number, thus exhibiting high detection efficiency for gamma rays and X-rays.
Huilei Optical Electric Technology