Measuring Temperature of Glass by Multiwavelength Pyrometry

A multiwavelength pyrometric technique estimates the surface and bulk (subsurface) temperatures of a hot glass. The multiwavelength pyrometer for which the technique was developed comprises a spectrometer plus a computer. The spectrometer can be operated in any of three wavelength ranges: 0.5 to 2.5, 0.6 to 4.5, or 2 to 14.5 µm; the range for a given measurement is generally selected according to the anticipated approximate temperature to be measured. The computer controls the spectrometer to acquire a spectrum, then analyzes the spectral data to determine the temperature.