High color-rendering flat lamps using quantum-dot color conversion films

TL;DR

This paper presents a simple method to create quantum-dot films that significantly improve the color rendering of LED flat lamps with minimal brightness loss, demonstrating practical application and reliability.

Contribution

It introduces a facile preparation process and a simulation algorithm for optimizing quantum-dot films in LED lamps, enhancing color rendering and efficiency.

Findings

Improved LED lamps from poor to high color rendering index (Ra up to 95)

Brightness drop limited to 15-20% after enhancement

Reliable performance over 1000 hours with PET barrier films

Abstract

Colloidal quantum dots are promising next-generation phosphors to enhance the color rendition of light-emitting devices (LEDs) while minimizing the brightness drop. In order to exploit the beneficial tunability of quantum dots for highly efficient devices, optimization and determination of the performance limit are of crucial importance. In this work, a facile preparation process of red-emission quantum dot films and simulation algorithm for fitting this film with two commercial LED flat lamps to the optimized performance are developed. Based on the algorithm, one lamp improves from cold-white light (8669 K) with poor color rendition ($R_{a}=72$) and luminous efficacy (85 lm/W) to warm-white light (2867 K) with $R_{a}=90.8$ and $R_{9}=74.9$, and the other reaches $R_{a}=93\sim95$. Impressively, the brightness drop is only about $15\sim20\%$. Furthermore, our device shows reliability over 1000 hours with only PET (polyethylene-terephthalate) films as the barrier, indicating that this auxiliary red-emission film can be easily applied to improve the color rendition of most commercial LED flat lamps.