Research On The Impact Of LED Spectrum And Illumination On Human Non-visual Effects

As a new type of light source, LED widely used in the indoor lighting, road lighting, electronic equipment and other aspects. Because the luminescence mechanism and mode of LED are completely different with the traditional light source and so dose the influence on human visual and non-visual effect. The research,the non-visual impact which the LED optical parameters have on human body, is very necessary. At the same time, finding the intrinsically photosensitive retinal ganglion cells provide the new research content and methods for the lighting science.Traditional lighting science only think about the lighting effects without considering the human health, the study of non-visual optical biological effect is very important.There are many light parameters which affect on the non-visual biological effects,including illumination, color temperature, light intensity, light spectrum. This paper research two kinds of light parameters, the LED illumination and light spectrum,which have influence on human non-visual effects.The illumination considered, this paper proposes a circuit model which is based on the Metal-Oxide-Semiconductor Field-Effect Transistor for non-visual photosensitive system. Through the analysis of mechanism of non-visual photo-sensitive system, this model is established using the analog equivalent method and is simulated.Combined with the new learning tools, flat panel display, the research is about the impact which different LED illumination of light environment have on the learning efficiency and fatigue of learners. By using the model, the inner mechanism of the learning efficiency and fatigue can be explained well. The visual fatigue and brain fatigue and learning efficiency considered, we can put forward reasonable lighting suggestions.The light spectrum considered, the non-visual effect of controllable LED light source on human circadian rhythms is evaluated by using a model of the circadian factor. All color LED light spectrum are measured by grating spectrometer. Then calculate the circadian factors of nine color LED light. The parameters of participants’ electrocardiogram in the blue, green and red light and the average temperaturedifference on forehead before and after turning on the light in the nine color light are recorded. Through the analysis and processing of the measured data, using a model of the circadian factor can reasonably explain for the data which provides data support for the dynamic lighting.This paper studies the impacts of new learning tool IPAD on the human non-visual biological effects from two aspects of LED illumination and light spectrum.The data about learning efficiency, visual fatigue, brain fatigue, ECG and temperature is measured. Their models are established to reasonably explain the data law which provides data and the theoretical basis for the lighting project.