Deep-ultraviolet LED lamp beads are obviously already the mainstream of shopping mall lighting. So how is the color temperature of the LED controlled?
LED color temperature is to change the share of different lights. Adding red light makes the color temperature warmer, and adding blue light makes the color temperature cooler. Adjust the brightness, change the size of the current flowing through the LED, the larger the current, the brighter. Otherwise, it will be darker. Deep ultraviolet LED lamp beads are not a monochromatic light, and there is no white light in the visible light spectrum. According to the research on visible light, the white light that human eyes can see can be produced by a mixture of two or more than two kinds of light. There are three different ways to obtain LED light sources.
1. Use the blue LED to illuminate the yellow phosphor to excite yellow light, and the yellow light will complement the blue light to generate white light again. However, the conversion power of the phosphor used in this method is low, and the color rendering index is not interesting.
2. After using LED lamp beads to stimulate the three primary color phosphors to produce multi-color light, then mix it to form white light. This method is better than the first kind of color rendering, but because the phosphors are mostly sulfides, the luminescence stability is poor, and the light decay is greater.
3. Three primary color LEDs form white light: this method is to combine three LED chips of green, red, and blue, energize them together, and then mix the declared green, red, and blue light according to a certain proportion to form white light. The white light obtained by the method of directly encapsulating the three-color LED into a white light LED has an excellent summary function. Under the premise of a high color rendering index, the white light lumen power is also very high. But this method is slightly more expensive.
Nowadays, light source products with dynamically adjustable LED color temperature are presented on the market. Their principle is to change the different light share of different light as mentioned at the beginning to end the color temperature scheduling. Choose a combination of different color LEDs, such as a combination of light and red and blue LEDs, and control the driving current of deep purple, red and blue LEDs separately to end adjustable white light with a color rendering index greater than 90 in different color temperature ranges. Lamps with adjustable color temperature and high color rendering, because the driving circuit is messy, the cost is higher.
