KSF red phosphor can emit red fluorescence with high color purity, and is considered to be a phosphor with excellent light and color properties. It has application prospects in the fields of high color rendering white LED lighting and high color gamut liquid crystal LED backlighting. However, the hydrolytic degradation and thermal degradation characteristics of KSF red phosphors greatly limit its application in white LEDs.

 

Bree's R&D team controlled and improved the crystallinity and surface microstructure of KSF crystals from the perspectives of wet chemical synthesis and surface modification, and made important breakthroughs in improving the anti-deterioration performance of KSF phosphors. The KSF red phosphor with both high light efficiency and low light decay is used in high color rendering white LEDs and high color gamut backlights. On the LCD backlight, the combination of KSF red powder and β-Sialon green powder can achieve a color gamut value of 95% NTSC; when used with aluminate and other color phosphors, it can achieve a series of high light effects such as color rendering index Ra90/95 High color rendering white light scheme, the light efficiency is more than 10% higher than that of conventional Ra90 white LEDs. At the same time, the brightness attenuation of 1000 hours of high temperature, high humidity and high temperature aging is less than 5%, and the color drift is less than 7‰.

 

Figure 1 Microscopic morphology of our KSF red phosphor

Figure 2 The white LED made with our KSF red powder has excellent aging performance

Figure 3 Ra90 white LED spectrum based on KSF red phosphor

 

Figure 4 Spectrum of LCD backlight made with our KSF red powder