The impact of indoor lighting on human health.

In daily life, we spend most of our time indoors. The lack of natural light is one of the important factors that lead to human circadian rhythm disorders, mental and emotional disorders and other physical and mental diseases; at the same time, unreasonable indoor light environment design can hardly meet and make up for people's physiological needs for natural light stimulation. The influence of light on human health The influence of light on human body mainly includes the following three aspects: 1. Visual function: sufficient light intensity level can make people see the target thing clearly in different environments; 2. Body rhythm function: sunrise and sunset The natural light and indoor lighting affect the body's biological clock, such as the cycle of sleep and awakening; 3. Emotional regulation: Light can also affect human emotions and psychology through its various characteristics, and play a role in emotional regulation. 1. Visual function One of the most basic elements in lighting design is the illuminance that lamps can achieve, which has the greatest impact on people's visual level. Only with sufficient illuminance can people see things clearly. Current lighting specifications provide illuminance recommendations for different room types, which are derived from the normal lighting requirements for typical activities in different rooms. It can ensure that people get good visual acuity when completing various indoor activities to avoid visual fatigue and minimize productivity decline. 'Architectural Lighting Design Standards' are related to residential standards. However, if the illumination is too strong in a certain space, or the angle of the lamp is not suitable, it may also cause glare, which may damage the human's visual ability. Glare refers to the serious unevenness of brightness in the visual field, and the excessively high brightness contrast causes strong stimulation to human vision. Glare will reduce people's visual function, and in severe cases, there will even be instantaneous perception of environmental details and loss of ability. Especially for children and the elderly, the visual systems of these two groups of people are in the stages of growth and decline respectively, and glare can easily cause irreversible damage to their visual systems such as myopia. 2. In addition to the most basic visual effects of body rhythm, light will directly affect human health in non-visual ways. The biological clock in the human body synchronizes physiological functions according to a 24-hour cycle, which is called the circadian rhythm. The natural light of sunrise and sunset and indoor lighting maintain our body's biological clock, such as the cycle of sleep and wakefulness. This is the rhythmic effect of light. A variety of physiological processes, including digestion and sleep, are all regulated by hormonal changes and interactions in this cycle. Studies have shown that the secretion cycle of melatonin has a great relationship with the external light and time cycle. The secretion of melatonin at night is 5-10 times that of the day. If the human body receives excessive light at night, it will hinder the secretion of melatonin, leading to disorder of the circadian rhythm of the human body. In addition, scientific research has also verified the effects of spectral distribution and light wavelength on the synthesis of melatonin. In the experiment, three kinds of fluorescent lamps of red (610nm), green (540nm) and blue (430nm) are used to illuminate the room before people go to bed, which proves that red light has the weakest inhibitory effect on melatonin synthesis, while green light has the strongest inhibitory effect; Strong light can inhibit the synthesis of melatonin in an instant, while weak light takes a relatively long time to produce the inhibitory effect. Therefore, if you do not pay attention to the choice of lamps in the lighting design, not only will the brain and various organs not be fully rested, the body’s resistance will decrease, but it will also cause symptoms such as insomnia, palpitation, dizziness, headache, and memory loss. Diseases such as blood pressure and neurasthenia. 3. The role of mood regulation The color rendering index and color temperature in lighting design have a significant impact on the psychological mood of the human body. Choosing lamps with appropriate color rendering index and color temperature in different indoor spaces can ensure that people in them are stable and peaceful. . To give a common example in life, the food under different lights in the picture below, which one makes you more appetite? The color rendering index and color temperature of the luminaire will affect the visual appeal, which can improve or reduce the comfort of residents. Poor color quality will reduce visual acuity and accurate presentation of illuminated objects. As in the above example, under lighting with lower color quality indicators, food, human skin tones and plants may appear dull or unsaturated, which will affect people's mood and appetite to a large extent. Therefore, by using lamps with high-quality color rendering capabilities, the beauty of the space and the distinction of colors can be enhanced. In daily lighting, the color temperature of the optional light source is usually between 2000K-6500K. The lower the color temperature, the more warm red light, which will give people a warm and comfortable feeling; the higher the color temperature, the more blue light that can make people produce Refreshing and clean feeling. Combining different color temperatures with illuminance will create different psychological states for people.