Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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A Study on the Design of Flexible Display Considering the Failure Characteristics of ITO Layer

플렉시블 디스플레이에서 ITO층의 파괴 특성을 고려한 설계연구

  • Kim, Min Gyu (Department of Mechanical Engineering, Graduate school of Korea Univ.) ;
  • Park, Sang Baek (Department of Mechanical Engineering, Graduate school of Korea Univ.) ;
  • Chae, Soo-Won (Department of Mechanical Engineering, Korea Univ.)
  • 김민규 (고려대학교 대학원 기계공학과) ;
  • 박상백 (고려대학교 대학원 기계공학과) ;
  • 채수원 (고려대학교 기계공학부)
  • Received : 2012.12.14
  • Accepted : 2013.03.14
  • Published : 2013.05.01
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Abstract

In recent years the interest on flexible display has been increasing as a future display due to its bendable characteristics. An ITO(indium tin oxide) layer, which is part of a flexible display, can be broken easily while bending because it is made of brittle materials. This brittle property can cause the malfunction of flexible display. To analyze fracture characteristics of ITO layer, bending test was conducted commonly. However, it is not possible to know specific phenomena on bended ITO layer by simple bending test only. Accordingly, in this study, the FE(finite element) model is developed similarly to a real flexible display to analyze stress distribution of flexible display under bending condition, especially on ITO layer. To validate FE model, actual bending test was conducted and the test results were compared with the simulation results by measuring reaction forces during bending. By using the developed model, FE analysis about the effect of design parameter (Thickness & Young's Modulus of BL) on ITO Layer was performed. By explained FE analysis above, this research draws a conclusion of reliable design guide of flexible display, especially on ITO layer.

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References

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