A study on the fabrication method of middle size LGP using continuous micro-lenses made by LIGA reflow

  • 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)
  • Published : 2007.11.30

Abstract

LCD-BLU (Liquid Crystal Display-Back Light Unit) of medium size is usually manufactured by forming numerous dots with $50{\sim}300\;{\mu}m$ in diameter by etching process and V-grove shape with $50\;{\mu}m$ in height by mechanical cutting process. However, the surface of the etched dots is very rough due to the characteristics of the etching process and V-cutting needs rather high cost. Instead of existing optical pattern made by etching and mechanical cutting, 3-dimensional continuous micro-lens of $200\;{\mu}m$ in diameter was applied in the present study. The continuous micro-lens pattern fabricated by modified LIGA with thermal reflow process was tested to this new optical design of LGP. The manufacturing process using LIGA-reflow is made up of three stages as follows: (i) the stage of lithography, (ii) the stage of thermal reflow process and (iii) the stage of electroplating. The continuous micro-lens patterned LGP was fabricated with injection molding and its test results showed the possibility of commercial use in the future.

Keywords

References

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