Research On Dynamic LED Lighting Related To Non-visual Biological Effects

The health is one of the topic of the most concern in present society. The body’s internal clock is responsible for controlling daily rhythms and the formation and secretion of some hormones. Before the advent of artificial light in sunlight has a decisive role in the formation of in the human body’s internal clock. With the continuous progress of medical and biological research has consistently shown that light entering the human eyes has, apart from a visual effect, also an important non-visual biological effect on the human body. It is amazing that there is a third type of photoreceptor in the retina of mammals. This novel photoreceptor cell type, an intrinsic photosensitive retinal ganglion cell (ipRGC), regulates many non-visual biological effects such as circadian timing, body temperature, heart rate, cortisol production, melatonin production and alertness. As we know, the spectrum of sunlight in a day is not a static, but the artificial light source’s is fixed. This is contrary to the laws of nature.This research focuses on the research of dynamic LED lighting based on non-visual biological effects. First, the non-visual biological effects are described and to study the relationship between it and the spectrum. Secondly, based on the traditional photometry and the photobiologycal safety and the non-visual biological effects the the new evaluation factors were given. Thirdly, based on the third class of non-light-sensitive cells in the human body biological effects of non-visual the dynamic lighting was designed based on the non-visual biological effects.two typical LED of different CCT were selected to produce different combinations of spectral with PWM modulation technique. Finally, the LED dynamic lighting is measured and the results were evaluated with the mathematical models for non-visual light effects. Test data was analyzed to find the function of the relationship between the conventional photometry and the non-visual biological effects. A basic advice was given on the modulation of the dynamic LED lighting according to this data.Paper was divided into six chapters. The first chapter was an introduction to introduce the research of the LED dynamic lighting and non-visual biological effects, and introduced in both domestic and foreign research status and shortcomings. The second chapter introduced the basic theoretical knowledge about the light. The third chapter introduces the theoretical knowledge of the photobiological effects which has two parts:photobiological safety and the non-visual biological effects. The fourth chapter focuses on the semiconductor dynamic lighting techniques and designed a dynamic LED lighting system. Based on the theory of the preceding narrative a new evaluation methods and factors for the quality of the LED dynamic lighting were proposed. The fifth chapter focuses on the of the measurement of the dynamic lighting. A new system was set up which is used to measure the photobiologycal safety. And also the spectrum and the flux and the CCT were tested. The impact factor was calculated using the model which was established by the Michaelis-Menten law. Chapter VI was the summary of this research and pointed out the deficiencies of this research and also is the outlook for this research.