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

  • Received : 2014.12.10
  • Accepted : 2015.01.08
  • Published : 2015.03.31


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.


UV LED;Silicone;Refractive index;Radiant flux;Viewing Angle


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Grant : 유무기 복합소재를 이용한 UV 경화기용 고효율 SMD 구조의 UV A 패키지 및 광원 모듈 개발

Supported by : 산업통상자원부, 한국산업기술진흥원, 호남지역사업평가원