Yoshitaka Mieda

Two-dimensional micromanipulation using liquid crystals

We developed a two-dimensional micromanipulation method using liquid crystals. The combination of the backflow effect in the twisted nematic cell and the electrostatic force for the naturally charged microparticles causes the net movement. By adjusting the polarity and the duty ratio of the rectangular voltage, the particles can be driven two-dimensionally and bidirectionally. The velocity of the particles depended on the duty ratio, amplitude, and frequency of the applied voltage.

Micromanipulation Method using Backflow Effect of Liquid Crystals

We developed a micromanipulation method using backflow effect of liquid crystals. By adjusting the polarity and the frequency of an applied voltage, the net movement of the microparticles dipped into liquid crystals is caused. The micromanipulation methods using the backflow effect are suitable for the micro and precise manipulation of microobjects that are difficult to handle, for instance microlens or micromirrors

Manipulation of microparticles using surface stabilized ferroelectric liquid crystals (Invited Paper)

We propose a strategy for a micromanipulation method using surface stabilized ferroelectric liquid crystals (SSFLC). By adjusting the frequency of the applied ac electric field, the surface layers that cannot follow an applied ac electric field are constructed in SSFLC. In addition, by applying a sawtooth wave voltage, net flow along the smectic layer is generated. The flow direction is reversed by changing the polarity of the sawtooth wave. Consequently, the particles dispersed in SSFLC can be driven bidirectionally along the smectic layer. The particle velocity depends on the temperature, amplitude and frequency of the applied voltage.