Pyrometry is the non-contact measurement of the temperature of an object, by measuring its self-emission and emissivity. An apparatus that measures the temperature by means of pyrometry is called a pyrometer or optical pyrometer. Emissivity is a measure of the object's capability to emit electromagnetic radiation. The value of emissivity ranges from 0 to 1, where the emissivity of a perfect emitter also known as a black body is 1, and a theoretical object that doesn't emit radiation at all has a… (More on Pyrometry)