This paper reviews sensing applications of optical fibre microwires and nanowires. In addition to the usual benefits of sensors based on optical fibres, these sensors are extremely compact and have fast response speeds. In this review sensors will be grouped in three categories according to their morphology: linear sensors, resonant sensors and tip sensors. While linear and resonant sensors mai...

Optical couplers are very important devices in optical communication systems and optical sensor systems. Several types of optical couplers with different materials or different transmission characteristics have been reported. Here we propose a semi-reciprocal polarization maintaining fibre coupler with unique transmission characteristics, which is distinct from conventional polarization maintai...

In this paper we described a structure of an original multiwavelength optical fiber source for DWDM systems. In order to obtain a several dozen of optical carriers with highly stable channel spacing of 4.5GHz a single laser source and acousto optic frequency shifter were used. Results of the analysis of the structure properties were presented. Key-Words: DWDM, EDFA, multiwavelength

We investigate the effect of noise loading in a hybrid phase-sensitive amplifier system, analyzing the effect of noise beating between the signal and idler waves coupled in a parametric amplifier. Through analyzing input and output optical signal to noise ratios, we find that system performance of a phase-sensitive amplifier is 3 to 6 dB improved over a phase-insensitive amplifier, depending on...

In the last decade optical fibre tapers with micrometer diameter (often called microfibers) have been investigated for numerous applications ranging from sensing to wavelength convertors, telecom and optical manipulation. This paper reviews the various applications of microfibres. 1. Optical microfibres Although microfibers with diameters comparable to the wavelength have been manufactured for ...

In this paper, a fibre laser at 546 nm has been studied for a signal power of -30 dB. Er-doped ZBLAN fibre has been used by upconversion pumping of a 980 nm laser diode. Gain saturation effect has been investigated in detail. Laser performance has also been discussed. An efficiency of 35% has been calculated with a length of 5 mm fibre laser. Results show that Er-doped ZBLAN is a promising cand...

A novel intensity-modulated optical fibre displacement sensor with convex reflector technology is described. A common form of the intensity-modulated optical fibre sensor performs its measurement by making use of a pair of straight optical fibres with a plane reflector. The reflected optical signal intensity changes as a function of change in displacement. This paper describes an alternative se...

A novel technique for a self-equalized distributed amplifier is presented by showing the analogy between transversal filters and distributed amplifier topologies. The appropriate delay and gain coefficients of amplifier circuit are obtained by a Fourier expansion of the raised cosine spectrum in the frequency range of 0-40GHz.

The parameters of an encapsulated semiconductor optical amplifier (SOA) are obtained by a proper extraction algorithm using a technique based both on measurements and modeling. The theoretical model is based on rate equations and the experiments use continuous wave optical gain curves measured for different injected currents and optical input powers. The algorithm analyses the derivatives of th...

A new optical fibre feed-through for use in subsea in-well optical fibre sensing systems is reported. The new feed-through is compatible for use with standard subsea Christmas Tree penetrators and allows multiple re-mating of the feed-through over the lifetime of the device. The system has been extensively tested under in-well conditions and found to conform to the performance requirements. The...