The CellaTemp® PKL 63 two-colour infrared thermometer has a rectangular measuring field. This is realized purely optically, i.e. without moving parts. The object to be measured can move freely within the measuring field. This makes it possible to reliably measure the temperature of moving objects such as vibrating wires. A rectangular measuring field is also more advantageous when the position of the measuring object varies, e.g. when billets or metal bars on a roller table are to be measured.