双轴向列相液晶在表面沟槽上锚定,3个指向矢之一平行于沟槽均匀排列.使用Berreman在研究单轴向列相时提出的弹性形变产生表面能的理论方法对双轴向列相液晶进行研究,得到了一个公式,在Berre-man模型中它描写弹性畸变对表面锚定的贡献,但在双轴向列相中,这一公式描写当n指向矢沿着沟槽锚定时,m指向矢受到沟槽表面的作用而产生的畸变能量.研究了双轴向列相液晶在表面沟槽上锚定的稳定性问题;稳定性条件在双轴向列相单一弹性常数近似下为n指向矢的弹性常数最大.
Biaxial nematic liquid crystal is anchored by the grooves of a surface, so that one of the three directors is homogeneously fixed in direction of the grooves. This paper used a theoretical method proposed by Berreman, which the contribution of elastic origin to the surface energy of an uniaxial nematic liquid crystal. A formula was obtained which attributed the surface anchoring to the elastic distortion in the Berreman model, but in the biaxial nematics, it describes the distortion energy of the m director induced by the grooves of a surface, when the n director is anchored along the grooves. The stability of the n director around the grooves was studied. In one-constant model for each director, the rude condition is that the elastic constant of the n director is the maximum.
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