Hollow-cathode lamp
= Hollow-cathode lamp
{wiki=Hollow-cathode_lamp}
A hollow-cathode lamp (HCL) is a type of gas discharge lamp that is widely used as a light source in atomic spectrometry, specifically for atomic absorption spectroscopy (AAS) and atomic emission spectroscopy (AES). The lamp is designed to emit characteristic spectral lines of a specific element or elements when an electric current is passed through the gas inside it.