]>Remote System for Detection of Low-Levels of Methane Based on Photonic Crystal Fibres and Wavelength Modulation Spectroscopy : Figure 3
398403.fig.003a
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398403.fig.003b
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Figure 3: (a) Project of the sensing head with periodic openings in the PCF fibre; (b) butt-coupling of HC-PCF pieces using standard zirconium ferrules connected with a standard zirconium mating sleeve.