Change of blue light hazard and circadian effect of LED backlight displayer with color temperature and age.

In order to provide a theoretical reference for the personalized design and color temperature adjustment of LED backlight displayer, the spectral distribution of the LED backlight displayer at different color temperatures (1200-6500K) was measured. According to the transmittance of human eye at different ages (1-100 years old), the effective spectral distribution of the LED backlight displayer on the retina of the human eye at different ages was calculated. Based on the fitting of the response function of the human eye, the correlation studies on the changes of the blue light hazard factor, the proportion of blue light in the range of wavelength 400-500 nm, the circadian rhythm factor, and the proportion of blue light in the range of wavelength 446-477 nm with color temperature and age were conducted respectively. The results showed that the blue light hazard and circadian rhythm increased with the increase of the color temperature while decreased with the increase of age. For one-year-old infants, when the color temperature increased from 1200K to 6500K, the blue light hazard factor and circadian rhythm factor of the effective spectrum of the retina increased by 12.2 and 9.5 times respectively. For a 6500K LED backlight displayer, when the age increased from 1-year-old to 100 years old, the corresponding value of the two factors decreased by 0.2 and 0.3 times respectively. The proportion of blue light in the range of wavelength 400-500 nm can be used to approximately replace the blue light hazard factor to demonstrate the degree of blue light hazard. This conclusion can provide a certain theoretical reference for the personalized design and use of LED backlight displayer from the perspective of blue light hazard and circadian rhythm.