Journal of the Korean Institute of Illuminating and Electrical Installation Engineers (조명전기설비학회논문지)

The Korean Institute of IIIuminating and Electrical Installation Engineers (한국조명전기설비학회)
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Optical Properties of UV LEDs depending on Encapsulate Method using Silicone Encapsulants with Different Refractive Indices

굴절률이 다른 실리콘 봉지재의 봉지 방법에 따른 UV-A LED의 광 특성에 관한 연구

  • 김완호 ;
  • 구대형 (전남대학교 일반대학원 전기공학과) ;
  • 노주현 (전남대학교 일반대학원 전기공학과) ;
  • 이경원 (전남대학교 일반대학원 전기공학과) ;
  • 전시욱 (한국광기술원 신조명연구본부) ;
  • 김재필 (한국광기술원 신조명연구본부 광원소재연구센터) ;
  • 여인선
  • Received : 2014.12.10
  • Accepted : 2015.01.08
  • Published : 2015.03.31
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Abstract

Optical characteristics including the radiant flux and viewing angle of UV LEDs were investigated according to both silicone encapsulants with different refractive indexes and lens shapes. Lead frame was fabricated using the enhanced heat dissipation characteristics with a heat slug structure and the reflector based on EMC(Epoxy Mold Compound) material. Four types of lens shapes were designed and their optical characteristics depending on the refractive index of silicone encapsulants were evaluated. The maximum radiant flux can be achieved when the height of lens are 1.32mm and 1.08mm for silicone encapsulants with low and high refractive indexes, respectively. Depending on the encapsulating method, the viewing angle changes from $148.9^{\circ}$ to $130.2^{\circ}$ for low refractive index and from $145.3^{\circ}$ to $136.8^{\circ}$ for high refractive index. As a result, it is found that the optical characteristics of UV LEDs can be controled through both encapsulating method and the refractive index of encapsulants.

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References

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