White LED spectrum for minimising damage to Chinese traditional heavy colour paintings

Optical radiation can cause permanent damage to the colours of high-responsivity Chinese traditional paintings. The white light emitting diode is flexible, efficient and can create similar colour phenomena with different spectra, making it easy to adjust the spectral irradiance distribution according to specific requirements. It is important to establish quantitative influence rules of white light emitting diode narrowband light for protecting traditional paintings, which optimises the constitution and proportion of the white light emitting diode spectrum according to the lowest damage level. In this study, we utilised typical narrowband spectra as light sources to illuminate Chinese traditional heavy colour paintings, and measured the CIELAB colour data periodically. We then calculated the colour difference based on the data and drew corresponding decay curves for the different pigments used. By analysing the quantitative influence characteristics, we were able to determine the quantitative influence and relative influence coefficient of each narrowband light type. These results provide a reference for the spectral irradiance distribution of the minimum-damage white light emitting diode for different heavy colour painting types based on the inorganic pigment characteristics.