Using Three-Component Hierarchical Structures to Improve the Light Extraction From White Leds Based on Red-Green-Blue Color Mixing Method

Abstract

Abstract-In this work, we present a three-component hierarchical structure to simultaneously improve the red, green, and blue (RGB) light extraction efficiency (LEE) of white light-emitting diodes (LEDs) based on color mixing method. With the help of 3D finite-difference time-domain (FDTD) simulations, the effects of the embedded photonic crystals (PhCs) the normal surface PhCs and the nano-rods on the enhancement of RGB light extraction were investigated. The results were compared with those of the conventional planar LEDs and the normal surface PhCs LEDs over the whole visible spectrum. Results from the simulations demonstrated that the maximum LEE for the hierarchical structures LEDs gave 112%, 327%, and 284% RGB LEE enhancement, respectively, compared to that of the conventional planar LEDs, and achieved 104%, 191%, and 187% RGB LEE enhancement compared to that of LEDs with normal surface PhCs. The emission characteristics of the hierarchical structures LEDs were also revealed in detail by FDTD simulations. The results shown in this paper would do a favor for the design and fabrication of high efficiency LEDs.

Effect of Selected Luminescent Layers on CCT, CRI, and Response Times

“…One of them is additive mixing of basic colors (red, green, and blue, i.e., RGB), and the second uses blue excitant light and a phosphor [1]. Some of the methods of producing white light using additive mixing are described; for example, in [2,3,4]. Producing white light with phosphors, i.e., on wavelength converters, has been more commonly used for many years, however.…”