Laser yellowing

Over the past few years there has been an increasing interest in researches related to the application of lasers in conservation, analysis and diagnostics of artwork surfaces. Among the many interesting problems to be tackled, one issue was drawing more interest because of the limitations it can impose on the use of lasers. Laser yellowing is a phenomenon wherein artwork surfaces assume a yellow hue when cleaned with Q-switched Nd:YAG (1064 nm) lasers in particular. Here the effect of yellowing has been studied and quantified for artwork surfaces (marble) using SFR Nd:YAG and LQS Nd:YAG lasers. Colorimetric measurements by employing a spectroradiometer helps to quantify the effect of yellowing by analysing three variables (chromaticity coordinates) of interest.