Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Preparation and Characteristics of PC and PMMA-Based Diffusers for LED Backlight Unit

PC 및 PMMA 수지를 이용한 LED 백라이트용 확산판의 제조 및 특성 연구

  • Kim, Nam Yi (Department of Chemical Engineering, Kyonggi University) ;
  • Kim, Hyo Jin (Department of Advanced Materials Engineering, Kyonggi University) ;
  • Kim, Dong Won (Department of Advanced Materials Engineering, Kyonggi University) ;
  • Jo, Jae Hyun (Department of advanced development, DS Co., Ltd.) ;
  • Kim, Seong Woo (Department of Chemical Engineering, Kyonggi University)
  • Received : 2012.02.09
  • Accepted : 2012.03.15
  • Published : 2012.03.31
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Abstract

The optical diffuser for direct-lit LED backlight unit was prepared by using extrusion compounding followed by thermoforming process. Poly(methyl methacrylate) (PMMA) with superior optical characteristics and polycarbonate (PC) with good thermal property were used as base resins, and crosslinked polystyrene (PS) and PMMA beads as diffusing agents were incorporated into resin matrix to derive light scattering and diffusing action. In the compounded plate, the diffusing beads were observed to be dispersed uniformly and distinctly in the continuous phase. The inclusion of polymeric beads up to 3 wt% substantially enhanced the optical characteristics such as luminance, luminance uniformity, haze for the diffuser. Two different diffusers of PC and PMMA-based compound with various compositions were compared in terms of measured optical, thermal, and mechanical properties, which would be expected to be utilized for the industrial application of LED backlight unit.

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References

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