White‐Light‐Emitting Diodes with Quantum Dot Color Converters for Display Backlights

Quantum dots (QDs) have attracted great attention as good candidate for the next generation displays due to their narrow emission, and high luminescence efficiency, and tunable emission covering all visible range. However, QDs easily lost their initial optical properties during the process for a device fabrication and practical operation. We synthesized well passivated green and red light emitting QDs that show almost 100% of QE. When the highly luminescent green and red light emitting QDs were applied as color converters in InGaN blue LEDs, resulting cool white QD-LEDs showed 41lm/W and more than 100% of color reproducibility compared to NTSC standard in CIE1931 and maintained their optical properties for a long time operation. We also demonstrated a 46-inch LCD panel using the white QDLED backlight was successfully demonstrated (Figure).

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