The paper presents an optoelectronic system for antenna beam control. Dispersion technique has been applied to build variable delay lines for wide bandwidth microwave signals. Optoelectronic beam scanning system configuration and measurements results have been presented. Key-Words: antenna, fibre optic, beam forming, optoelectronics, laser.

Pumping of highly-nonlinear microstructured fibers with zero-dispersion around the pump wavelength of a 50kW peak-power picosecond Yb-fiber laser allowed extensive polychromatic picosecond operation down to 525nm in all-fibre format. Spectral power densities over 1mW/nm and potential of further pulse compression to femtoseconds is demonstrated.

We numerically investigate the energy and arrival-time noise of ultrashort laser pulses produced via resonant dispersive wave emission in gas-filled hollow-core waveguides under influence pump-laser instability. find that for low pump energy, fluctuations are strongly amplified. However, when generation process is saturated, can be significantly less noisy than pulse. This holds a variety condi...

This paper summarizes the state of the art of direct metal laser-sintering (DMLS) in 2004, put into perspective by a review of its history from its roots in the 1970s, and discusses the trends going into the future. Since the 1970s, DMLS has evolved from an idea to a powerful commercial technology. The "family tree" of DMLS is explained with reference to related methods such as laser-cladding, ...

We perform a full numerical characterisation of half-open cavity random DFB Raman fibre laser amplifier schemes for WDM transmission in terms of signal power variation, noise and nonlinear impairments, showcasing the excellent potential of this scheme to provide amplification for DWDM transmission with very low gain variation.

A distributed feedback laser is fabricated in Er3+-doped photonic crystal fibre. Preferential single-mode lasing is obtained with no special consideration of polarisation issues. The results demonstrate practical implementation of a multi-photon writing process for complex structures in these optical fibres. No hydrogen loading and no germanium are involved.

Introduction: High repetition rate optical pulses in a few picosecond range and below are playing an increasingly important role in high speed optical fibre communication systems. Such high repetition rate short pulses are routinely generated by harmonically modelocked lasers [1], but with the following limitations: (i) complicated feedback control is required; (ii) the modelocked frequency com...

waveguides in LiTaO3 written by high-repetition rate ultrafast laser Ben McMillen, Kevin P. Chen, Honglin An, Simon Fleming, Vincent Hartwell, and David Snoke Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA Optical Fibre Technology Centre, University of Sydney, Sydney, New South Wales 1430, Australia Department of Physics and Astr...

The present work demonstrates a fibre-laser system with automatic electronic-controlled triggering of dissipative soliton generation mode. Passive mode locking based on the effect of non-linear polarisation evolution has been achieved through a polarisation controller containing a single low-voltage liquid crystal plate whose optimal wave delay was determined from analysis of inter-mode beat sp...