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The current state of-and future plans for-the micro eledro mechanical CAD system SESES developed at the ETH Zurich are presented. The algorithmic requirements for the numerical modelling of microelectromechanical (MEM) devices are presented with reference to six important modelling problems. Numerical results are given for an electrostatic comb actuator.

The bistability in a chiral-splay nematic liquid crystal cell, which is obtained by adding a chiral additive to a splay cell, is proposed. In this letter, we describe a horizontal way of switching between the two states of the bistable chiral-splay cell, one state being characterized by a nontwisted director field with splay, the second state showing a director-field with 180° twist. The optimization of the various parameters of the device is described.

Pretilt angle measurable by using the conventional crystal rotation method is limited to about 0°–20° and 70°–90°. We propose a method by which we can measure the pretilt angle by using the crystal rotation method even if the pretilt angle is between 20° and 70°. In this method, the determination of a pretilt angle is achieved by finding the rotation angles where transmittances are maximum and minimum in the periodic transmittance characteristics obtained with the variation of rotation angle.

The stabilization of the metastable 180 degrees twist state in a bistable chiral splay nematic liquid crystal device is studied. The stability of the metastable 180 degrees twist state is explained using the azimuthal anchoring strength, which is a function of the twist elastic constant and the cell gap. A stable 180 degrees twist state as well as the permanent retention time can be obtained by increasing the anchoring energy above a certain threshold.