METHOD FOR ASSESSING LIGHT DAMAGE TO PLANTS CAUSED BY NIGHT LIGHTING, METHOD OF ASSESSING PROPERTIES OF NIGHT LIGHTING, AND LIGHTING DEVICE FOR AVOIDING LIGHT DAMAGE

摘要

Lamina of plants having been grown in an artificial climate chamber with or without night lighting are collected and treated. The gene expression amounts in the individual samples thus obtained are determined by using a gene analysis technique and a light damage avoidance ratio is calculated as the ratio of these gene expression amounts, thereby assessing light damage to plants. Thus, light damage to plants caused by night lighting can be appropriately and effectively assessed. Provided is a lighting device for avoiding light damage, wherein the pulsed light frequency and duty ratio of a pulsed light source are set to give a light damage avoidance ratio of 0.8 or higher. By combining multiple pulsed light sources, the average color rendering index is enhanced so as to achieve a natural feeling as a night lighting device. Thus, the night lighting device, which is to be installed close to a vegetation area, can give a natural feeling to humans without causing light damage to plants.