Contactless measurement of temperature of coloured material

摘要

The method employs a white light source with an optical system through which light is directed at the coloured surface and reflected to a spectrometer, photodetector and electronic signal processor. The reflectance is compared with that of a standard sample at two known temperatures, one of which is preferably room temperature. The standardised signal is either displayed or applied in analogue or digital form to a process controller. The measurement is made in a spectral region where the material has an interband transition touching an absorption edge.