Research On Lighting Index Of Museum Exhibition Based On Photaesthesia Cultural Relic Substrate And Colloid Damage

Lighting will cause irreversible permanent damage to photaesthesia cultural relics,such as fading,discoloration,hair black,etc.,seriously affecting the historical and artistic value of cultural relics.Among them,such as calligraphy,painting and ancient books,are the highest light-sensitive exhibits stipulated by the International Commission on Illumination.They have a high vulnerability and are also the key types of research.General building lighting only needs to meet the basic use requirements of personnel,while museum lighting needs to ensure the light safety of cultural relics besides the ornamental requirements of personnel.It has dual attributes of visual comfort and light protection,which should be met simultaneously,so the research is difficult and slow.Code for Lighting Design of Museums has not been updated for ten years.In order to protect the cultural objects more scientifically,it is an urgent problem to be solved in this field.At present,in the lighting standards of museums,the lighting indicators such as color temperature,illuminance and annual exposure are specified,but there are still key problems to be solved.In the aspect of color temperature,because there are many light sources to meet the needs of museum lighting,especially LED is introduced into museum lighting,its spectrum is flexible and adjustable.Even if it meets the requirements of color temperature specified in the lighting standards of museums,the damages caused by different cultural relics are different,among which there is the same color spectrum of the light source,which makes the research more complex and meaningful;In the aspect of illumination,the primary consideration of museum lighting is the protection of photaesthesia cultural relics.The illuminance is limited to 50 lx,which is only to meet the minimum requirements of people’s viewing without considering the visual comfort.However,there are differences in the sensitivity of different types of cultural relics to light absorption,and the illumination limit of 50 lx is stipulated,which can not achieve reasonable display lighting.The problem is that 50 lx can’t make the elderly with general vision decline fully appreciate the details in painting and calligraphy;In terms of annual exposure,there is no scientific explanation of the damage to cultural relics in the standard.In view of the problems in the above indicators.Firstly,ten kinds of narrow band spectrum are used as experimental light source.Taking the painting and calligraphy substrate and colloid as the experimental objects,the long-term illumination experiment was carried out,through the analysis of the experimental results,the relative damage coefficient and the damage curve with the exposure of different band narrow-band light sources are obtained,and ten spectra are iterated and superposed to eliminate the spectrum that does not meet the requirements of the museum’s color rendering.Secondly,according to the relative damage formula of cultural relics,the relative damage difference of spectrum is calculated,and the average relative damage minimum value in each color temperature range is selected as the best color temperature.Thirdly,according to the damage formula of cultural relics,the damage difference of cultural relics in one year and ten years after irradiation under different illuminance values is calculated.By comparing the damage difference of one year after irradiation,the illuminance range of cultural relics is determined.By the damage difference of ten years after irradiation,the damage difference of several years after irradiation is given under reasonable illumination.The research results determine the museum lighting indicators based on the protection of painting and calligraphy substrate and colloidal light,which establishes the theoretical basis for the establishment of the protective lighting standards of light sensitive cultural relics.