The Research Of Lighting Based On The Physical Signs Of Biological Effects Of Light

Light emitting diode(LED), a new generation of light source, is better than the traditional light source in such aspects as luminous efficiency and control. And it has more and more obvious advantages in indoor lighting and intelligent equipment. In addition, the found of the intrinsically photosensitive retinal ganglion cells(ip RGCs) has brought new research contents and methods for the lighting engineering. And the non-visual biological effects of light cause the attention of scholars both at home and abroad. Non-visual biological effect of light is the effect that light impacts human body’s physiological signs, rhythm system and hormone content through the eyes. The operational factors are the illumination, color temperature, spectrum and so on. This paper study the non-visual biological effects of light through the illumination, color temperature and spectrum of LED.In the matter of illumination and color temperature, we set up the experimental environment and platform which can adjust the light source and illumination and had carried on two experiment. One is measuring the electrocardiogram of 12 college boys under the environment of red, green and blue LED in 1 lx, so as to find out whether the effect still exists under low illumination. The results showed that under low illumination can cause human body electrocardiogram(ecg) changes, and according to the different color light source the ecg parameters have different changing laws. The other is measuring the heart rate and blood pressure of 6 college boys under the condition of two different color temperature and five illuminance, so as to find out whether the change of color temperature and illuminance impact the heart rate and blood pressure. The results showed that there are different impacts in heart rate and blood pressure. Further study of the heart rate and other physiological signs of non-visual biological effects of light has important significance on perfecting the photometric lighting standards.In the matter of spectrum, this paper discusses three calculation models that evaluate the size of the non-visual biological effects of light. We used the grating spectrometer to measure nine kinds of color LED spectrum and found out the advantages and disadvantages of the models from the theoretical analysis. Then we measured the forehead temperature of 4 college boys under nine kinds of color LED lighting and built the relationship of the theoretical calculated value and actual forehead temperature change. By this means, we improved the practical application value of the models.In the self-built experimental environment, this paper analyzes the impacts to the electrocardiogram, blood pressure and forehead temperature in the non-visual biological effects of light experiment. The results provide reference and theory basis to the improvement of the evaluation of the non-visual biological effects.