Method for obtaining high-color rendering white light by using white-light LED and red-light LED with fixed fluorescent powder proportioning ratios

Abstract

The invention relates to a method for obtaining high-luminous effect and high-color rendering LED white light by combining a white-light LED and a red-light LED with different color temperatures and fixed fluorescent powder proportioning ratios, which is realized by the white-light LED, the red-light LED and a control circuit. The white-light LED comprises a blue-light chip, yellow fluorescent powder and green fluorescent powder, wherein the yellow fluorescent powder and the green fluorescent powder are mixed by specific luminous flux and proportioning ratio, and then a high-luminous effect white-light LED with different color temperatures is obtained through changing the percentages of the mixture yellow and green fluorescent powder and a packaging material. The method comprises the following steps of: selecting the combination of the high-luminous effect white-light LED and the red-light LED with different color temperatures according to the white-light color temperature of the required LED combination, and respectively supplying different driving currents to the white-light LED and the red-light LED through the control circuit according to the requirements of the white-light luminous flux of the required LED combination to obtain the high-luminous effect and high-color rendering LED white light with adjustable luminous flux, wherein the general color-rendering index Ra of the high-luminous effect and high-color rendering LED white light is greater than 90, and the special color-rendering index R9 is greater than 80.

Description

technical field [0001] The invention relates to the technical field of LED white light, in particular to a method for obtaining white LED light with high light efficiency and high color rendering by combining white light with red light LEDs with different color temperature and fixed phosphor powder ratio. Background technique [0002] With the birth of blue LED chips and corresponding red phosphors, yellow phosphors and green phosphors, white LEDs have developed rapidly. However, the color rendering of this white LED is not high, and its color rendering index Ra is generally lower than 85. In order to improve the color rendering index, red phosphor powder needs to be added, but its light efficiency is greatly reduced, making it difficult to be practically applied. Therefore, a red LED or chip was proposed to replace the red phosphor powder and combine with a white LED to produce white light, which achieved high color rendering white light, but the white light deviates from ...

AI Technical Summary

Problems solved by technology

However, the color rendering of this white LED is not high, and its color rendering index Ra is generally lower than 85.

In order to improve the color rendering index, red phosphor powder needs to be added, but its light efficiency is greatly reduced, making it difficult to be practically applied

Therefore, a red LED or chip was proposed to replace the red phosphor powder and combine with a white LED to produce white light, which achieved high color rendering white light, but the white light deviates from the black body locus, dC>0.01, and its color temperature ranges from 2700K to 6500K. Special color rendering index R 9 It is still low, and the actual visual color rendering is not very ideal, so further improvement is needed to achieve a color temperature range of 2700K to 6500K, the general color rendering index Ra is greater than 90, and the special color rendering index R 9 Higher high light efficiency and high color rendering LED white light

Images