We demonstrate polarizer-free and fast response microlens arrays based on optical phase modulation of polymer-stabilized blue phase liquid crystal (PSBP-LC). Polarization-independent optical phase shift is because the propagation of an incident light is along the optic axis of PSBP-LC, and birefringence of PSBP-LC induced by Kerr effect results in electrically tunable optical phase shift. The measured optical phase shift of a PSBP-LC phase modulation is around π radian at 150 Vrms for the cell gap of 7 μ. The response time is about 3 ms. The focal length is around 13.1 cm at 100 Vrms.

Nanowire-based nanoelectronic devices will be innovative electronic building blocks from bottom up. The reduced nanocontact area of nanowire devices magnifies the contribution of contact electrical properties. Although a lot of two-contact-based ZnO nanoelectronics have been demonstrated, the electrical properties bringing either from the nanocontacts or from the nanowires have not been considered yet. High quality ZnO nanowires with a small deviation and an average diameter of 38 nm were synthesized to fabricate more than thirty nanowire devices. According to temperature behaviors of current-voltage curves and resistances, the devices could be grouped into three types. Type I devices expose thermally activated transport in ZnO nanowires and they could be considered as two Ohmic nanocontacts of the Ti electrode contacting directly on the nanowire. For those nanowire devices having a high resistance at room temperatures, they can be fitted accurately with the thermionic-emission theory and classified into type II and III devices according to their rectifying and symmetrical current-voltage behaviors. The type II device has only one deteriorated nanocontact and the other one Ohmic contact on single ZnO nanowire. An insulating oxide layer with thickness less than 20 nm should be introduced to describe electron hopping in the nanocontacts, so as to signalize one- and high-dimensional hopping conduction in type II and III devices.

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Polarization-independent phase-only modulation of a polymer-dispersed liquid crystal ͑PDLC͒ is demonstrated. In the low voltage region, PDLC is translucent because of light scattering. Once the voltage exceeds a saturation level, PDLC is highly transparent and exhibits phase-only modulation capability. Although the remaining phase is not too large, it is still sufficient for making adaptive microdevices, such as microlens. A tunable-focus microlens for arrays using PDLC is demonstrated. This kind of microlens is scattering free, polarization independent, and has fast response time.