Performance enhancement of white light-emitting diodes using an encapsulant semi-solidification method†
Abstract
High-optical-quality white light-emitting diodes (LEDs) are leading candidates for next-generation lighting and numerous other potential applications. In this work, a simple and innovative strategy based on semi-solidification was used to prepare white LEDs with a highly uniform illumination distribution. Semi-solidification facilitates uniform dispersion of fluorescent phosphors throughout the LED encapsulant by adopting a B-stage intermediate step, thereby enabling superior color uniformity in the LED. This approach is based on the control of the curing process and offers a reasonable and effective solution for problems associated with conventional LEDs, including the yellow ring phenomenon that arises from non-uniform illumination. Our novel and simple approach provides a facile route for the fabrication of novel, high-performance LED encapsulants. This method is effective for the enhancement of luminous efficacy, long-term stability, and color uniformity of LEDs, indicating their potential use in industrial and practical applications.