From Artificial Lighting to Natural Lighting – Paradigm Shift of Lighting
In this and last newsletters, we are summarizing important messages from the previous newsletters. Last week, we briefly covered the importance of the natural light in human health, and this week, I’d like to revisit how animals and plants adapted to natural light over evolutionary time and how we can use these traits to our advantage.
Plants elaborately control every leave morphology to maximize light absorption. Light quality is also important in growth and nutritional quality of crop plants. Two-week cultivation of lettuce under SunLike, the LED product of Seoul Semiconductor radiating the light closest to sunlight resulted in 13.5% more weight and 40% higher accumulation flavonols (Figure 1).

(Figure 1) (a) Weight and (b) flavonol content in lettuce grown under white LEDs and SunLike for two weeks.
Effect of light on animals is not as evident as in plants, but natural lighting environment is also very important for animals’ well-being. To sea fish, green is the color of natural light. Light from green LEDs creates comfortable and stress-free environment for flatfish in the fishfarm that 30 to 40% less reactive oxygens and lipoperoxides are found in the fish (Figure 2).

(Figure 2) Effects of Green light on flatfish
It is very natural that plants and animals that have spent evolutionary time with the sun are most healthy under natural light. It gets clear that the light close to sunlight puts huge influence on human’s well-being. This is why the lighting paradigm should transform from simply ‘light’ to ‘the light close to natural light’.
Soo-Young Moon Ph.D. Electronic & Information Engineering 
Jinwon Kim, Ph.D. Biologist
Jae Ho Lee, Ph.D. Biologist 

* Next week’s Topic: Light and Snell's law

You can find "Interesting Story about Light Science” series on the link below. 
Seoul Semiconductor / 
97-11, Sandan-ro 163beon-gil, Danwon-gu, Ansan-si, Gyeonggi-do, Republic of Korea