Journal of the Optical Society of Korea

  • 제18권4호
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  • Pages.370-376
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  • 2014
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  • 1226-4776(pISSN)
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  • 2093-6885(eISSN)
한국광학회 (Optical Society of Korea)
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Improvement of Light Extraction Efficiency of LED Packages Using an Enhanced Encapsulant Design

  • Choi, Hyun-Su (Department of Display Engineering, Hoseo University) ;
  • Park, Joon-Sik (Department of Materials Science & Engineering, Hanbat National University) ;
  • Moon, Cheol-Hee (Department of Display Engineering, Hoseo University)
  • 투고 : 2014.03.31
  • 심사 : 2014.06.11
  • 발행 : 2014.08.25
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초록

We optimized the design of the flat encapsulant of a light-emitting diode (LED) package to obtain higher light output power (LOP), both by experiment and simulation using three-dimensional ray-tracing software. In the experiment, the refractive index of the encapsulant was varied (1.41 and 1.53). In addition, double-layer structures with these refractive indices (1.41/1.53) were investigated by varying the shape of the interface between the two among flat, concave, and convex. The experiments showed that the LOP of the double-layer encapsulant with convex interface increased by 13.4% compared to the single-layer encapsulant with a refractive index 1.41, which was explained by the increase of the light extraction efficiency (LEE) in connection with the increase of the critical angle (${\theta}_c$) and the decrease of the Fresnel reflection.

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피인용 문헌

  1. Investigation of Light Extraction by Refractive Index of an Encapsulant, a Package Structure, and Phosphor vol.6, pp.12, 2016, https://doi.org/10.1109/TCPMT.2016.2616122
  2. Effect of radius of curvature of a convex interface on the light output power of light-emitting diode package with double-layered encapsulant vol.16, pp.4, 2015, https://doi.org/10.1080/15980316.2015.1088900
  3. Using nanoimprint lithography to improve the light extraction efficiency and color rendering of dichromatic white light-emitting diodes vol.7, pp.39, 2015, https://doi.org/10.1039/C5NR02988K