High-quality light source is the basis of green lighting. Quality light source should have the following three characteristics.
First, the spectral composition should be no UV and infrared light. Receiving long-term excessive ultraviolet radiation, is not only easy to cause keratitis, but also on the lens, retina, choroid and other damage. Infrared easily absorbed by water, the infrared excess gathered through the human lens absorbs when Jibei, degeneration occurs over time the lens, causing cataracts.
Second, the light color temperature should be close to natural light. The long-life in natural light, the human eye adaptability of natural light, visual effect is good.
Third, the frequency of light is not flashing. Ordinary fluorescent power supply frequency of 50 Hz, that light the dark when the light 100 times per second, a low frequency of the strobe light will make the regulation of the human eye in a tight regulation of the state organs, resulting in visual fatigue. If the light when the frequency increased to hundreds, tens of thousands of cycles per second or more — a high frequency, the human eye that does not have strobe feeling; but the real DC power supply is not flicker or semiconductor light-emitting solid device (such as the led light diode) light from the flash frequency is called free.