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We discuss alignment properties of nematic liquid crystals on surfaces that contain homeotropic and planar alignment areas on the same surface substrate. The basic idea is to locally pattern homeotropic agents (silane) on surfaces that usually lead to plan ...
Optically active liquid-crystalline side-chain polysiloxanes have been prepared by grafting planar chiral ferrocene-based vinyl monomers onto commercially available polyhydrosiloxane. Two ferrocene monomers have been synthesized: a linear-type monomer, whi ...
Liquid crystal (LC) microlenses have a variable focal length with a change in applied voltage. These lenses have suitable dimensions and focal length variations for a wide range of applications where the absence of moving parts is favored. In this article ...
The optical properties of plano-convex refractive microlenses with low Fresnel Number (typically FN < 10) are investigated. It turns out that diffraction effects at the lens aperture limit the range of the effective focal length. The upper limit of the foc ...
With help of liquid crystal polymers (LCP) a polarization sensitive diffuser has been realized. By using convex microstructures made of LCP and an index matching layer, two distinct functions depending on the orientation of the device and the polarization ...
We propose an artificial three-dimensional material that exhibits a strong resonance in the effective permeability in the visible spectral domain. This material may be implemented in a two-step procedure. First, a metamaterial made of densely packed metall ...
A new optical concept for compact digital image acquisition devices with large field of view is developed and proofed experimentally. Archetypes for the imaging system are compound eyes of small insects and the Gabor-Superlens. A paraxial 3×3 matrix formal ...
Liquid crystalline blue phases (LCBP) and their diffraction patterns were investigated experimentally and theoretically. We measured the diffraction pattern for different wavelengths of monochromatic light with the help of a conoscopic setup of a polarizat ...
The use of chemical nanopatterns through nanoimprint lithography ato align a nematic liquid crystal (LC) in LC cells was described. It was found that the ratio of areas with different surface-aligning helped in the polar orientation of LC, while the azimut ...
High Resolution Interference Microscopy (HRIM) is a technique that allows the characterization of amplitude and phase of electromagnetic wave-fields in the far-field with a spatial accuracy that corresponds to a few nanometers in the object plane. Emphasis ...
