Review of lighting deterioration, lighting quality, and lighting energy saving for paintings in museums

There are needs to consider three requirements of reducing lighting deterioration, improving lighting quality and lighting energy saving for paintings, the high-light-sensitive exhibits in museums whose lighting environment is quite special and complex. Therefore, based on lighting parameters composed of the spectral power distribution of light sources, the spectral response of painting materials, the irradiance or illuminance, and the irradiation time, it is necessary to review researches on paintings in museums from the above three requirements, including the existing research contents, methods, and suggestions. Based on parameters concerning lighting deterioration, its mechanism and model have been partly clarified and established, following by applications of light sources aiming to better conserve paintings and needing further researches, namely, the lighting deterioration evaluation, the formulation of lighting quantity standards, and the spectral control and adjustment, etc. As for lighting quality, the needs of visitors for colour perception and visual comfort have been evaluated. However, it's urgent to study the model between the lighting quality and its related lighting parameters, which can optimize lighting applications above considering both needs by combining the models of lighting deterioration and lighting quality. The third aspect focuses on lighting energy saving whose strategies involve the replacement and control of energy-saving lamps, mainly for the LED and its spectral control and adjust system, as well as controlling the illuminance and irradiation time. While expanding the knowledge of paintings in museum lighting for researchers in related fields, this paper emphasizes some remaining issues that can be studied in the future.