<abstract xmlns="http://www.w3.org/1999/xhtml">This paper investigates a method for improving the lighting performance of white light-emitting diodes (WLEDs), packaged using two separating remote phosphor layers, yellow-emitting YAG:Ce phosphor layer and red-emitting α-SrO·3B2O3:Sm2+ phosphor layer. The thicknesses of these two layers are 800 μm and 200 μm, respectively. Both of them have been examined at average correlated color temperatures (CCT) of 7700 K and 8500 K. For this two-layer model, the concentration of red phosphor has been varied from 2 % to 30 % in the upper layer, while in the lower layer the yellow phosphor concentration was kept at 15 %. It was found interesting that the lighting properties, such as color rendering index (CRI) and luminous flux, are enhanced significantly, while the color uniformity is maintained at a level relatively close to the level in one-layer configuration (measured at the same correlated color temperature). Besides, the transmitted and reflected light of each phosphor layer have been revised by combining Kubelka-Munk and Mie-Lorenz theories. Through the analysis, it is demonstrated that the packaging configuration of two-layered remote phosphor that contains red-emitting α-SrO·3B2O3:Sm2+ phosphor particles provides a practical solution to general WLEDs lighting.</abstract>

This paper investigates a method for improving the lighting performance of white light-emitting diodes (WLEDs), packaged using two separating remote phosphor layers, yellow-emitting YAG:Ce phosphor layer and red-emitting α-SrO·3B2O3:Sm2+ phosphor layer. The thicknesses of these two layers are 800 μm and 200 μm, respectively. Both of them have been examined at average correlated color temperatures (CCT) of 7700 K and 8500 K. For this two-layer model, the concentration of red phosphor has been varied from 2 % to 30 % in the upper layer, while in the lower layer the yellow phosphor concentration was kept at 15 %. It was found interesting that the lighting properties, such as color rendering index (CRI) and luminous flux, are enhanced significantly, while the color uniformity is maintained at a level relatively close to the level in one-layer configuration (measured at the same correlated color temperature). Besides, the transmitted and reflected light of each phosphor layer have been revised by combining Kubelka-Munk and Mie-Lorenz theories. Through the analysis, it is demonstrated that the packaging configuration of two-layered remote phosphor that contains red-emitting α-SrO·3B2O3:Sm2+ phosphor particles provides a practical solution to general WLEDs lighting.

Novel lighting properties of white LEDs with two-layered remote phosphor package using red-emitting α-SrO·3B2O3:Sm2+ phosphor

Materials Science-Poland

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Novel lighting properties of white LEDs with two-layered remote phosphor package using red-emitting α-SrO·3BO:Sm phosphor

This paper investigates a method for improving the lighting performance of white light-emitting diodes (WLEDs), packaged using two separating remote phosphor...

Novel lighting properties of white LEDs with two-layered remote phosphor package using red-emitting α-SrO·3B₂O₃:Sm²⁺ phosphor

Published Online: Oct 31, 2017

Page range: 618 - 625

Received: Feb 10, 2017

Accepted: Aug 22, 2017

DOI: https://doi.org/10.1515/msp-2017-0071

Keywords
remote phosphor structure, two-layered package, luminous flux, color rendering index, light emitting diodes (LEDs)

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Novel lighting properties of white LEDs with two-layered remote phosphor package using red-emitting α-SrO·3B2O3:Sm2+ phosphor

Published Online: Oct 31, 2017

Page range: 618 - 625

Received: Feb 10, 2017

Accepted: Aug 22, 2017

DOI: https://doi.org/10.1515/msp-2017-0071

Keywordsremote phosphor structure, two-layered package, luminous flux, color rendering index, light emitting diodes (LEDs)

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Novel lighting properties of white LEDs with two-layered remote phosphor package using red-emitting α-SrO·3B₂O₃:Sm²⁺ phosphor

Keywords
remote phosphor structure, two-layered package, luminous flux, color rendering index, light emitting diodes (LEDs)