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A Study on the Simulation and DSF Molding of V-groove Type Light Guide for a Backlight Unit

백라이트 유닛용 V-그루브 도광판의 전산모사 및 DSF성형에 관한 비교연구

  • 조광환 (단국대학교 대학원 기계공학과) ;
  • 윤경환 (단국대학교 기계공학과)
  • Published : 2005.06.01

Abstract

Nowadays, TFT-LCD is widely used as display unit of many digital devices. And, the backlight unit(BLU) is used as a light source of TFT-LCD module. In the backlight unit, the most important component is a light guide, which guides the input light to the TFT-LCD module uniformly. Recently, many researchers have focused on improving the efficiency of BLU by changing the design and structure of a light guide. In the present paper, a series of simulation was performed to find the optimal luminance distribution of emanated light from the given geometry as the first step. From the results of simulations for the light guide with given V-groove pattern, the emanated light from it is mostly affected by the groove angle. In the case of acute angle, about 74 degrees was found as optimal angle to satisfy the restrictions of angular luminance distribution, FWHM, the maximum luminance, etc. However, as far as the average luminance value was concerned, the case of 120 degrees(abtuse angle) was found to be the best while prism films were added to the BLU. As a next step the light guide samples of 74 and 120 degrees were manufactured by DSF method, which was recently proposed by the authors. Of course, most of design parameters were chosen by the aid of simulation results. Finally, the results of average luminance values were compared between the simulation and DSF molded samples.

Keywords

References

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