Pyrometer

The pyrometer can also measure the temperature by reflected IR radiation – this can help when working with hard-to-reach parts: it is not necessary to try to get access to a heated part, its reflection in the mirror is enough to measure the temperature. But the same advantage of the pyrometer turns into the most significant disadvantage – reflected infrared light makes it difficult to measure the temperature and the object of interest to us, because some part of the IR radiation coming from it is reflected. The higher the reflectivity of the material, the greater the error in the result of the reflected rays. To exclude this error, you should know the emission coefficient of the surface of the object whose temperature you are measuring.