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Fabrication of micro injection mold with modified LIGA micro-lens pattern and its application to LCD-BLU  

Kim, Jong-Sun (Precision Mold Team, Korea Institute of Industrial Technology (KITECH))
Ko, Young-Bae (Precision Mold Team, Korea Institute of Industrial Technology (KITECH))
Hwang, Chul-Jin (Precision Mold Team, Korea Institute of Industrial Technology (KITECH))
Kim, Jong-Deok (Precision Mold Team, Korea Institute of Industrial Technology (KITECH))
Yoon, Kyung-Hwan (Mechanical Engineering, Dankook University)
Publication Information
Korea-Australia Rheology Journal / v.19, no.3, 2007 , pp. 165-169 More about this Journal
Abstract
The light guide plate (LGP) of LCD-BLU (Liquid Crystal Display-Back Light Unit) is usually manufactured by forming numerous dots by etching process. However, the surface of those etched dots of LGP is very rough due to the characteristics of etching process, so that its light loss is relatively high due to the dispersion of light. Accordingly, there is a limit in raising the luminance of LCD-BLU. In order to overcome the limit of current etched-dot patterned LGP, micro-lens pattern was tested to investigate the possibility of replacing etched pattern in the present study. The micro-lens pattern fabricated by the modified LiGA with thermal reflow process was applied to the optical design of LGP. The attention was paid to the effects of different optical pattern type (i.e. etched dot, micro-lens). Finally, the micro-lens patterned LGP showed better optical qualities than the one made by the etched-dot patterned LGP in luminance.
Keywords
back light unit(BLU); thin-film-transistor liquid-crystal-display (TFT-LCD); light guide plate (LGP); LIGA; micro-lens; injection molding;
Citations & Related Records

Times Cited By Web Of Science : 6  (Related Records In Web of Science)
Times Cited By SCOPUS : 6
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