Journal of the Institute of Electronics Engineers of Korea SD (대한전자공학회논문지SD)

The Institute of Electronics and Information Engineers (대한전자공학회)
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A Study on the director distribution of In-Plane Switching liquid crystal cell by finite element method

유한요소법을 이용한 IPS 모드의 액정 분자 거동 해석 연구

  • Jeong, Ju-Sik (Dept.of Electronics Electric Engineering, Inha University) ;
  • Yun, Sang-Ho (Dept.of Electronics Electric Engineering, Inha University) ;
  • Lee, Cheol-Su (Dept.of Electronics Electric Engineering, Inha University) ;
  • Won, Tae-Yeong (Dept.of Electronics Electric Engineering, Inha University)
  • 정주식 (인하대학교 전자전기공학부) ;
  • 윤상호 (인하대학교 전자전기공학부) ;
  • 이철수 (인하대학교 전자전기공학부) ;
  • 원태영 (인하대학교 전자전기공학부)
  • Published : 2002.04.01
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Abstract

This paper reports a methodology for calculating distribution of the director in an In-plane switching liquid crystal cell by a numerical technique. To calculate distribution of the director, we developed a three dimensional finite element method (FEM) and calculated the distribution of electric potential and electric field in the liquid crystal cell. We have considered the free-energy density composed of electric potential and strain energy in the bulk of liquid crystal cell and calculated the switching property of liquid crystal cell by the Ericksen-Leslie equation and the Laplace equation We generated 1,859 nodes and 8,640 elements for IPS mode cell with 24${\mu}{\textrm}{m}$$\times$12${\mu}{\textrm}{m}$$\times$4.5${\mu}{\textrm}{m}$ and performed transient analysis until 16ms. As a result, horizontal electric field occurred at cell region except liquid crystal region above electrodes and the disclination occured on electrodes.

본 논문에서는 IPS모드의 액정 셀에서 전압에 따른 액정 거동을 수치 해석적으로 계산하는 방법을 보고한다. 액정 거동을 해석하기 위해 복잡한 구조에 적용이 용이한 3차원 유한 요소법을 사용하여 액정 셀 내부의 전압 분포와 전계 분포를 계산하였다. 전기 에너지와 액정 분자의 탄성 에너지로 이루어지는 액정 셀 내부의 자유에너지 밀도를 고려하였으며, 에릭슨-레슬리(Ericksen-Leslie) 방정식과 라플라스(Laplace) 방정식을 해석함으로서 액정 셀의 스위칭 특성을 계산하였다. 24㎛×12㎛×4.5㎛ 사이즈의 IPS 모드 액정 셀에 대하여 1,859개의 노드와 8,640개의 사면체 요소를 생성하여 16ms까지 과도 해석하였다. 그 결과, 전극 위 부분을 제외한 영역에서 횡방향의 전계가 형성되었고, 전극 위 영역에서 전경선(disclination)이 발생하는 것을 확인하였다.

Keywords

References

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