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Long period gratings: technology and parameters

Long Period Gratings (LPGs) are essential components for many modern telecommunication and metrology systems. The main purpose of presented work was the preliminary test on fabrication of such structures using ultraviolet irradiation and point-by-point technique. The UV 244 nm 100 mW Coherent argon-ion frequency doubled laser was used in the experiments. Long period gratings of different fiber suppliers and for different writing condition were inscribed. Influence of periods values or structure lengths on attenuations bands and gratings strength were investigated. Significant parameters in relation to future sensing applications are temperature and strain sensitivity. We have investigated behavior of LPGs in temperature range of 25-100oC. Good temperature stability of long period gratings was observed by placing them in 100oC for few hours in the temperature chamber.