Micro-Prism Patterned Remote Phosphor Film for Enhanced Luminous Efficiency and Color Uniformity of Phosphor-Converted Light-Emitting Diodes

Abstract

In this work, we propose micro-prism patterned remote phosphor (RP) films to enhance both luminous efficiency and color uniformity (CU) of remote phosphor-converted light-emitting diodes (rpc-LEDs) simultaneously. On the incident surface of the RP film, one micro-prism film is used to extract backward light by double reflection. On the exit surface, the other micro-prism film is adopted to retain blue light inside the RP film, thus enhancing the phosphor excitation. Experimental results show that double prism-patterned RP (DP-RP) film configuration shows a luminous flux of 55.16 lm, which is 45.1% higher than that of RP film configuration at 300 mA. As regards the CU, the DP-RP film configuration reduces the angular CIE-x and CIE-y standard variations by 68% and 69.32%, respectively, compared with the pristine device. Moreover, the DP-RP film configuration shows excellent color stability under varying driving currents. Since micro-prism films can be easily fabricated by a roll-to-roll process, the micro-prism patterned RP film can be an alternative to a conventional RP layer to enable the practical application of rpc-LEDs.

Modeling and Simulations of 4H-SiC/6H-SiC/4H-SiC Single Quantum-Well Light Emitting Diode Using Diffusion Bonding Technique

“…In recent years, the astonishing features of solid-state LEDs such as high luminous efficiency, high color rendering index (CRI), and longevity have made them promising candidates to replace conventional light sources [3]. The current research trends involve a systematic investigation of a variety of organic/inorganic materials for a wide range of optoelectronic applications [4][5][6][7][8][9][10].…”

Editorial for the Special Issue “Microsystem for Electronic Devices”

“…This Special Issue includes 12 high-quality papers focused on the development of microsystems. Half of the published papers focus on light-emitting diode (LED) microsystems and related microelectronic systems [4][5][6][7][8][9], three papers discuss the cooling techniques of electronic microsystems [10][11][12], and the final three papers present several mechanical microsystems [13][14][15].…”

“…The filter and scattering characteristics of phosphors generate two luminous areas on the converter, and the lighting effects can be adjusted using tilt angles. When the tilt angle is 20 • , the luminous flux increases by 11.5% and the maximum temperature reduces by 22.8% under the same luminous flux and correlated color temperature of 6500 K. Yu et al [6] proposed micro-prism patterned remote phosphor films, made by large-scale roll-to-roll imprinting, to significantly improve the light and color performance of LEDs. The micro-prism film on the incident surface of the remote phosphor film extracts backward light through a double reflection and the micro-prism film on the exit surface retains blue light inside the remote phosphor film to enhance phosphor excitation.…”