Transactions on Electrical and Electronic Materials

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
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EO Performances of Flexible TN-LCD using in-situ Ultraviolet Exposure during Imidization of Polyimide on the Polymer Film

  • Moon, Hyun-Chan (Department of Electrical & Electronic Engineering, Yonsei University) ;
  • Hwang, Jeoung-Yeon (Department of Electrical & Electronic Engineering, Yonsei University) ;
  • Lee, Whee-Won (Department of Electrical & Electronic Engineering, Yonsei University) ;
  • Seo, Dae-Shik (Department of Electrical & Electronic Engineering, Yonsei University)
  • Published : 2005.06.01
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Abstract

We have investigated the generation of pretilt angle for a nematic liquid crystal (NLC) alignment with in-situ photoalignment method on polyimide (PI) surfaces using polymer films. Especially, we studied in-situ photoalignment changing heating temperature from $50^{\circ}C\;to\;120^{\circ}C$ on the polymer film. The LC aligning capabilities and pretilt angle on the polymer substrates were better than those on the glass substrate using in-situ photoalignment method. It is considered that this increase in pretilt angle may be attributed to the roughness of the micro-groove substrate induced by the in-situ photoalignment. As temperature of heated subtrate and UV exposure time increase, pretilt angle of the cell used polymer film increased. It is considered that the heating temperature of substrate is attributed to generate pretilt angle. Also, electro-optical performances of the in-situ photoaligned TN cell using the polymer substrate are almost the same as that of the TN cell using the glass substrate.

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References

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