There has always been an important and complex issue in the museum exhibition design of the museum, which is the problem of light damage. When we use the light of the cultural relics, we usually pay attention to the lighting effect of the light, but often ignore the damage of the light on the cultural relics. Many artifacts can cause damage even under normal light, even if the damage is not serious, but these damages are permanent. This not only affects the viewing effect, but also brings an incalculable loss to the country. Therefore, for a variety of lighting-sensitive cultural relics, the lighting design must not be considered to meet the visual conditions, but should pay special attention to the protection of exhibits to avoid damage from light radiation. This has caused us to have a contradiction in the process of cultural relics exhibition. If we want to better characterize the cultural relics, we must use light. However, as long as there is light, it will cause damage to cultural relics, especially photosensitive cultural relics. Therefore, the issue of cultural relics in the museum exhibition Chen has become a problem we must solve.
At present, the country has introduced some standards concerning the lighting of museum exhibitions, but these standards do not provide comprehensive guidance for us to prevent the light damage in the museum exhibition. For the museum, the exhibition of cultural relics is mainly the exhibition hall, which shoulders multiple functions such as display display, audience activities and cultural relics protection. Therefore, in the process of displaying lighting design, not only to create a good visual environment for the audience, but also to improve the illumination of the exhibits, we must properly protect these precious historical and cultural properties from optical radiation (including visible radiation, Damage to ultraviolet radiation and infrared radiation). The light-free lighting design of the exhibition area must meet the needs of the light distribution of each object of the cultural relic exhibit. It is also necessary to reduce the damage caused by the light on the exhibits during the exhibition and the harm to the viewer caused by the poor light environment.
First, the harm of light on cultural relics exhibits
The light source of the museum cultural relics exhibition process is mainly divided into natural light and artificial light. Natural light mainly refers to the external natural light source introduced by the museum's own building structure considering the light effect, which is basically sunlight. Artificial light refers to the artificial lighting that is added to the theme because of the need for display expression. Basically, it is the light source emitted by various types of lamps.
The damage caused by light action can be mainly divided into two categories: thermal damage and damage caused by photochemical reaction. Thermal damage is caused by infrared rays in the light source. The infrared radiation causes a local thermal effect, which causes the relative humidity of the irradiated object to change, resulting in shrinkage, deformation or cracking of the artifact. [1] Damage caused by photoaging is visible damage such as color change and qualitative change. Although light can only damage the objects it reaches. Due to most artifacts
The surface is opaque, so the main role of light is to degrade the surface. The surface is the essence of many exhibits, especially calligraphy, oil painting, painting, murals and textiles. Therefore, all organic materials are at risk under the illumination of light. (The term "organic material" includes all organic matter in animals and plants, such as: paper, cotton, linen, wood, lacquer, parchment, silk, etc.) In addition, due to the similar chemical structure, almost all synthetic dyes and plastics In the category of organic materials, it must also be noted that light not only causes color changes but also enhances such changes, such as textiles and damage to some pigment solvents.
Of course, due to the special condition of stone, metal, glass and ceramics, it is less affected by light, or for wood, bone or ivory, if the surface color does not matter, but the damage to light is still present. And it is also permanent, only to a lesser extent. It can be seen from the above discussion that the hazard of light hazard in the use of cultural relics is self-evident. Light hazards cannot be restored or fundamentally changed by means of protection, so this light hazard is minimized during the display process.
Second, the current major cultural relics exhibition anti-light measures and problems
From the perspective of light radiation on cultural relics, cultural relics should be protected from light, but as cultural relics witnessed by human history and culture, it is inevitable to carry out various exhibition activities, that is, cultural relics should be used, and if they are not used, they will lose their cultural relics. The meaning. Therefore, cultural relics must implement a series of anti-light measures during the display and display process. At present, the main measures for cultural relics are:
1. Reduce the exhibition time of cultural relics
Cultural relics not only have historical value, but he also has social value at present, so the cultural relics have to be displayed to the public. By reducing the exposure time of artifacts. If using (1) limited display of cultural relics (; 2) or lighting only when there is an audience (; 3) try to use the copy. Although this method reduces the damage of light to cultural relics to a certain extent, it is a measure at the expense of viewers' viewing. Even some precious cultural relics may never have a chance to see.
2, lighting control
In the process of cultural relics exhibition, most of the light damage comes from artificial lighting. In order to reduce the damage, it is generally taken to reduce the illumination, adjust the illumination angle to increase the distance of the illumination, and pretend the filter for the lamp. The same method has problems. Due to the decrease of illumination and the increase of the distance of illumination, the visual environment of the displayed space is affected. The viewer stays in such a space for a long time, which is prone to problems such as visual fatigue.
3. Personnel monitoring during the exhibition process
In the process of exhibition, in order to prevent the light from harming cultural relics due to the instability of the light source or the mistakes of the audience, the museum will send special staff to patrol the site and pay attention to the changes around the exhibits. However, this has also increased the operating costs of many museums, especially in some comprehensive museums. The expenditure of personnel expenses has become its main burden, while other expenses such as the purchase of cultural relics, scientific research, and stadium renovation will be affected.