Stock Photo - ICP-OES. Inductively coupled plasma atomic emission spectroscopy (ICP-AES), also referred to as inductively coupled plasma optical emission spectrometry (ICP-OES), is an analytical technique used for the detection of trace metals. It is a type of emission spectroscopy that uses the inductively coupled plasma to produce excited atoms and ions that emit electromagnetic radiation at wavelengths characteristic of a particular element. The intensity of this emission is indicative of the concentration of the element within the sample. Determination of metals in liquid samples. Inorganic laboratory. Energy and Environment Division. Tecnalia Research and Innovation. Donostia. San Sebastian. Gipuzkoa. Basque Country. Spain.