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The advent of cell phone cameras extensively pushed market needs for micro lenses and supported developments like the Wafer-Level-Camera Technology [1]. Different optical applications and patterning methods for micro lenses require different sets of materi ...
Spontaneously broadened emission from a distributed feedback laser diode perated just above threshold is used as a pump source in Brillouin slow light systems. The pump spectrum could this way be extended to several GHz. ...
Ieice-Inst Electronics Information & Communication Engineers, Kikai-Shinko-Kaikan Bldg 103, 5-8, Shibakoen 3 Chome, Minato-Ku, Tokyo, 105-0011, Japan2010
Optical fiber sensors based on stimulated Brillouin scattering have now clearly demonstrated their excellent capability for long-range distributed strain and temperature measurements. The fiber is used as sensing element, and a value for temperature and/or ...
We propose and experimentally demonstrate a new method to extend the range of Brillouin optical time domain analysis (BOTDA) systems. It exploits the virtual transparency created by second-order Raman pumping in optical fibers. The idea is theoretically an ...
In this Letter, we propose the use of optical pulse coding techniques for long-range distributed sensors based on Brillouin optical time-domain analysis (BOTDA). Compared to conventional BOTDA sensors, optical coding provides a significant sensing-range en ...
We experimentally demonstrate a novel technique to process broadband microwave signals, using all-optically tunable true time delay in optical fibers. The configuration to achieve true time delay basically consists of two main stages: photonic RF phase shi ...
A novel BOTDA technique for distributed sensing of the Brillouin frequency in optical fibers with cm-order spatial resolution is proposed. The technique is based upon a simple modulation scheme, requiring only a single long pump pulse for acoustic excitati ...
We present useful expressions predicting the filling time of gaseous species inside photonic crystal fibers. Based on the theory of diffusion, this gas-filling model can be applied to any given fiber geometry or length by calculating diffusion coefficients ...
Distributed optical fiber Brillouin sensors provide innovative solutions for the monitoring of temperature and strain in large structures. The effective range of these sensors is typically of the order of 20–30 km, which limits their use in certain ...
The presented research has been carried out within the European project Intelligent Roads (INTRO). The major objective followed was to assess the potential of optical fiber for pavement monitoring in comparison with classical strain gauges. Thus, both meas ...
