White light led lamp and method for generating white light with high color rendering

Abstract

The invention discloses a white light LED lamp and a method for generating white light with high color rendering. The white light LED includes a substrate with high thermal conductivity and an LED chipset arranged on the substrate with high thermal conductivity. The LED chipset includes at least two blue chips and at least one red chip , the blue light chip and the red light chip are connected with a control circuit that can adjust the size of the current output; it also includes a fluorescent lens arranged above the LED chipset, and yellow fluorescent powder and green fluorescent powder are evenly distributed in the fluorescent lens. The white light LED lamp of the present invention uses at least two blue light chips and at least one red light chip, combined with yellow phosphor and green phosphor, to form four continuous peak wavelengths to generate a white light with high color rendering, high light efficiency and adjustable color temperature LED.

Description

technical field [0001] The invention relates to the field of white light LEDs, in particular to a high-color-rendering, high-efficiency, color-temperature-adjustable white-light LED lamp and a method for generating high-color-rendering white light. Background technique [0002] The production of white light LED is currently most commonly used to use the blue light chip as the excitation light source to excite the YAG phosphor to obtain yellow light, and the yellow light is mixed with the remaining blue light of the blue light chip to form a white light LED. This kind of white LED has high luminous efficacy and color rendering at high color temperature, but at low color temperature, the color rendering is too poor, and the color deviates greatly from general lighting applications. To solve this problem, the red phosphor is usually added to the yellow phosphor to improve the color rendering. However, due to the low conversion efficiency of the current red phosphor, its luminou...

AI Technical Summary

Problems solved by technology

This kind of white LED has high luminous efficiency and color rendering at high color temperature, but at low color temperature, the color rendering is too poor, and the color deviates greatly from general lighting applications.

To solve this problem, the red phosphor is usually added to the yellow phosphor, and the color rendering can be improved. However, due to the low conversion efficiency of the current red phosphor, its luminous flux is greatly reduced, and it is difficult to be practically applied.

To solve this problem, red chips are usually used instead of red phosphors to improve color rendering. However, due to the low luminous efficiency of the red chip itself, the luminous efficiency of white LEDs is also relatively low, so further improvement is needed.

[0003] Since the phosphor powder of white LEDs is usually mixed with potting glue and coated on the chip, and the coating area of ​​the chip is very small, it is difficult to precisely control the coating thickness and shape of the phosphor powder, resulting in the color of the emitted light Inconsistent, poor color rendering; and as the temperature rises, the quantum efficiency of the phosphor decreases, the light output decreases, and the radiation wavelength will also change, which will cause changes in the color temperature and color difference of white LEDs. Higher temperatures will also accelerate the aging of phosphors

Therefore, this white LED that directly coats the phosphor on the surface of the chip has problems such as light scattering and low light extraction efficiency.

Chinese patent CN201262377Y discloses a method of adding a transparent thin plate with high transmittance uniformly coated with yellow phosphor powder on the bottom surface above the chip, which can improve the quantum efficiency of the phosphor powder, but the higher temperature may cause some phosphor powder to fall off question

Chinese patent CN101988636A discloses a phosphor lens arranged on the light output path of a blue-ray chip or an ultraviolet LED, wherein the phosphor lens is made by injecting YAG phosphor powder into the lens. This method can reduce the aging problem of the phosphor powder, but the color rendering property is poor. Poor, needs further improvement

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