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Due to the fantastic properties and diverse applications of specific beams, optical beam shaping has attracted intensive attentions recently. Generally, these beams can be converted from Gaussian beams via particular spatial amplitude or phase control. In this work, we present a liquid crystal photopatterning technique based on dynamic microlithography with a polarisation-sensitive photoalignment agent. This technique enables the accurate, arbitrary and reconfigurable azimuthal angle control of liquid crystals, thus providing a powerful approach for the manipulation of light. By this means, the tailoring of arbitrary fine microstructures with binary or continuously space-variant liquid crystal azimuthal orientations are demonstrated. We briefly review our recent work on some specially designed patterns and corresponding specific optical fields. High-quality vortex beams, vector beams and Airy beams are generated with unprecedented flexibility in the design and control of light wavefront. Besides high efficiency, good electrical switchability and broad wavelength tolerance, the proposed devices also exhibit merits of compact size, low cost, dynamic mode conversion and polarisation controllable energy distribution, and are available for short pulse and intense light modulation. This work may pave a bright way towards beam shaping and bring new possibilities for the design of novel advanced liquid crystal photonic devices. [ABSTRACT FROM PUBLISHER]

The carbon fibres were used to enhance the materials by selected laser sintering. Gas phase oxidation, dense nitric acid and the coupling reagent processing together with dense nitric acid were adopted to modify carbon fibres, the microstructure of carbon fibres surface after treatment were analysed by SEM, and the strength of the composites was tested. The results demonstrate that the carbon fibre modified by 65-68% KHNO3 + 1% KH550 is considered as the optimal method. With the increase of carbon fibres content, the strength of the composite increases first and then decreases within a certain range. When the carbon fibres content at 3 wt-%, the green strength and the post-curing strength reached 0·87 and 9·614 MPa respectively, and the rate increased by 55·21 and 32·17% compared to the unreinforced. [ABSTRACT FROM AUTHOR]