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Low driving voltage is achieved in full color reflective display based on polymer-stabilized blue phase liquid crystal (PS-PBLC), by doping a small amount of ferroelectric nanoparticles. Both reflectance spectra of PS-PBLC with and without BaTiO₃ ferroelectric nanoparticles are studied under different applied external voltages. Superior to PS-PBLC without ferroelectric nanoparticles, the vertical driving electric fields of PS-PBLC with 0.4 wt.% BaTiO₃ ferroelectric nanoparticles are dramatically reduced by more than 70% for red, green and blue cells. The proposed approach would accelerate the practical application of full color PS-BPLC reflective display.

Because of their non-diffraction and freely acceleration during propagation, finite energy Airy beams are interesting for application such as optical manipulation, plasma channel generation and optical vortex generation. Especially interesting are tunable/switchable Airy beams, in which the Airy beam tuning by electric field, temperature or optical intensity can be realized. Here we experimentally demonstrate polarization-independent, electrically tunable/switchable Airy beam based on polymer-stabilized blue phase liquid crystals with wide working temperature range and fast response time through a structure called vertical field driven mode.

Inspired by Babinet's principle, we proposed a new plasmonic structure for enhancing the optical magnetic field, i.e. split ring aperture, whose complement is the well-known split ring. The split ring aperture exhibits a much better performance under radially polarized excitation than linearly polarized excitation. We attribute the ultra-high intensity enhancement in magnetic field to the symmetric matching between the aperture geometry and the direction of the electric field vector in each direction of radially excitation. The impact of the design parameters on the intensity enhancement and resonant wavelength is also investigated in details.

The observation of spatial angle dependent lasing from a dye-doped two-dimensional photonic crystal (2D PC) holographic polymer dispersed liquid crystals made of hexagonal lattice structure is reported. With the increasing output angle of the laser beam in the plane perpendicular to the 2D PC, the lasing wavelength is red-shifted. By analyzing the lasing oscillation trace, we found that the effective lattice constant changes with the output angle, causing the spatial angle dependent lasing.

Using polymer-dispersed liquid crystals (PDLCs), an electrically switchable binary phase pattern was fabricated to generate Airy beams through a programmable lithographic system. The right main lobe of the reconstructed Airy beam experienced 1.3 mm transverse deflection within 24 cm propagation distance. With a suitable voltage applied, the binary PDLC pattern can be erased due to the index match between polymers and liquid crystals. This versatile approach can be also used to generate other special beams with electrically tunable capability.

An electrically switchable computer-generated hologram (CGH) was fabricated using a liquid crystal (LC) cell. A polymethylmethacrylate (PMMA) film, which was spin-coated on one glass substrate of the LC cell, was patterned by a focused 2 MeV proton beam with a CGH phase pattern (2 microm resolution). With an applied voltage on the LC cell CGH sample, an index modulation was produced between the regions with and without PMMA because of the reorientation of LC molecules under the external electric field. The maximum diffraction efficiency measured was about 28.7%. The operating voltage was below 15 V(rms).

A tunable microlens array by printing was demonstrated. An UV-curable adhesive, NOA65, was printed and cured to form a lens array profile on an ITO glass. Then this microlens array ITO glass was assembled with a normal ITO glass to form a cell, which was later filled with a liquid crystal. The focal length of the lens array can be tuned by an electric field, which changes the index difference between liquid crystals and NOA65 due to the reorientation of the LC molecules. In our experiment, the focal length varied from -2.29 cm to 3.12 cm when the applied voltage was increased from 0 V to 13.26 V., ((c) 2009 Optical Society of America)