Multilayer design of hybrid phosphor film for application in LEDs

Abstract

blended into the system, the electrostatic interaction of negatively charged YAG:Ce 3þ and positively charged red phosphor particles caused remarkable clustering and heterogeneity in particle dispersion. Consequently, the light is dominantly blue and shifted to cold white. In other case, phosphor particles were sprayed onto the diffused polycarbonate substrate in stacked layers. Coatings with >80% inorganic content by mass with a thickness of 60 mm were subjected to thermal crosslinking, which the presence of the phosphor particles obstructed, presumably due to the hindrance of large phosphor particles in the diffusion of PDMS precursors. The coating of YAG:Ce 3þ first followed by red phosphor in stacked layers produced better light output and color properties than the coating obtained by spraying the mixture at once. Monte Carlo simulation validated the hypothesis.

A Review on Halide Perovskites as Color Conversion Layers in White Light Emitting Diode Applications

“…However, this approach suffers from low color rendering index (CRI) due to red deficiency and high correlated color temperature (CCT). To overcome this problem, additional phosphors (red phosphor, for instance) can be integrated into the system, or red, blue, and green phosphors (RGB) can be used as conversion layers over UV or near UV (n‐UV) LED chips. With the growing use of pc‐WLEDs, phosphor consumption increases, and the need for phosphor will lead to challenges in the future in terms of their cost and availability, since they contain rare earth elements .…”

Optimization and performance of nitrogen-doped carbon dots as a color conversion layer for white-LED applications

“…In Fig. 3, the white-light properties, such as CRI, CCT, and LER, that represent the efficacy of the produced light on the human eye (calculated by considering the human eye sensitivity [35,60]) together with the total visible light output (luminous flux) are presented as a function of the N-CDot amount. At the lowest N-CDot amount (15 µL), there is no valid registered CRI (filled circles) or CCT (empty circles) output.…”

“…We use remote-phosphor configuration, which color conversion layer(s) placed a particular distance away from LED chip, throughout this study. Details of this configuration can be found in our previous study [35].…”

Green fabrication of lanthanide-doped hydroxide-based phosphors: Y(OH)3:Eu3+ nanoparticles for white light generation

“…[7][8][9][10][11][12][13] Among those, Cerium doped Yttrium Aluminum Garnet (YAG:Ce 3+ ) is a wellknown yellow phosphor that is employed in a LED package together with blue LED to form white light (WLED). [14][15][16][17][18][19] In such a case, blue light partially absorbed by the phosphor after interacting with the color conversion layer, which is followed by a down-converted yellow emission. Combination of the remaining blue light and yellow emission above the conversion layer generate white light.…”