Spectral characteristics of radiation reflected diffusely by the surface of a ceramic tile

The spectral characteristics of radiation diffusely reflected by the surface of a ceramic tile under continuous and pulsed irradiation are compared. The effect of UV radiation on experimental samples is studied. It is shown that the phenomenon of triplet absorption resulting in visible-range phosphorescence is characteristics for ceramic glaze irradiated with a flash lamp. However, the effect of UV radiation on glaze is the appearance of radiation color centers in the glassy network which absorb visible light. All this gives rise to a discrepancy between the results of instrument and visual assessment of the color of a ceramic tile.