• 한국전기전자재료학회논문지
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• 제18권7호
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• pp.635-640
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• 2005

In this paper, we have improved a novel high tilted optically compensated bend (OCB) (HTOCB) mode by using high tilt angle that was generated by the unique baking condition on the homeotropic alignment layer. The high tilt angle of liquid crystal (LC) was generated by new alignment process that tilt angle changed homeotropic state to homeogenous state using Hot-plate equipment; we obtained about $40\~50^{\circ}$ tilt angle with negative and positive dielectric anisotropy on the homeotropic polyimide (PI), and then LC tilt angle decreased as increasing baking temperature and time. At last, we obtained about $10^{\circ}$ with positive type NLC $({\Delta}n>0)$. Also, the LC tilt angle of positive type NLC $({\Delta}n>0)$ decreased as increasing rubbing strength at the same baking temperature and time. The novel LC operating mode (HTOCB) that used the high tilt angle by the new alignment method was improved. The response time of the novel HTOCB cell was faster than that of conventional OCB cell. We suggest that the developed the novel HTOCB cell using control of tilt angle on the homeotropic surface is a promising technique for the achievement of a fast response time and a high contrast ratio.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
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• pp.181-184
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• 2005

In this paper, we have improved a novel fast response time liquid crystal operating mode using tilt angle in the unique condition by hot-plate equipment. The new control of tilt angle for nematic liquid crystal (NLC) with negative and positive dielectric anisotropy on the rubbed homeotropic polyimide (PI) using baking method by Hot-plate equipment was investigated. LC tilt angle decreased with increasing baking temperature and time. Especially, the low LC tilt angle of positive type NLC (${\Delta}n$>0) on the rubbed homeotropic PI surface by increasing temperature and time was measured. The EO characteristics of the high tilted OCB(HTOCB) mode using control of tilt angle on the homeotropic surface than that of conventional OCB cell can be improved. We suggest that the developed the HTOCB cell using control of tilt angle on the homeotropic surface is a promising technique for the achievement of a fast response time and a high contrast ratio.