Light is the main component of the physical environment of the human settlement space, and has a multi-dimensional health effect of "vision-physiology-psychology". Through the reasonable setting of light quantity, spatial light distribution, light source spectrum and light strategy, as well as the customized design of light landscape and light art media interface, light is used as a direct, effective, safe and no side effect active health intervention method for the living environment to eliminate the The negative impact of environmental pathogenic factors has very important research significance.

New research shows a link between street lights, neon signs and other forms of nighttime outdoor lighting and insomnia and mood disorders in teens. Compared with teens with lower nighttime light levels outdoors, teens living in areas with high nighttime artificial lighting levels went to bed about 29 minutes later on average and slept 11 minutes less than teens in areas with the lowest nighttime outdoor light. Adolescents exposed to higher levels of artificial light at night were more likely to meet diagnostic criteria for bipolar disorder or specific phobias.

Taiwan Industrial Research Institute has newly developed "human factor lighting" technology, which can stimulate the production of melatonin in the human body by adjusting the wavelength of the light source, and improve sleep quality. It has been proved by experiments that it can greatly improve deep sleep by 17%. Light therapy used to be used in psychiatric wards for seasonal depression in high latitudes as an adjunct to improve sleep. The technology newly developed by ITRI uses natural light to filter out the wavelengths of light that can cause depression in patients, so that patients can improve their condition or sleep quality. After clinical evaluation, it can significantly reduce patients' depression symptoms and shorten the time to fall asleep. 

A body of public health evidence suggests that prolonged exposure to abnormal nighttime light can lead to depressive-like mood and cognitive impairment, but little is known about the neural mechanisms behind it. Xue Tian's research group from the School of Life Sciences, University of Science and Technology of China and the Key Laboratory of Brain Function and Brain Diseases, Chinese Academy of Sciences, for the first time described the structure and function of neural circuits that mediate abnormal nighttime light-induced depression-like phenotypes; proved that abnormal nighttime light Rather than rhythm or sleep disturbances causing depressive-like behaviors, and finding that the excitability of this circuit is modulated by circadian rhythm gating is the first to elucidate the underlying mechanism of the diametrically opposed emotional effects of light during day and night.