Basic principles, role and significance of Fibre-optic sensors in measuring systems technology. Fundamentals of photonics. Light sources and photodetectors used in fibre-optic sensors. Optical fibres technology and properties. Passive optical components in fibre technology. Fibre and integrated components for sensing. Measurement techniques and principles. Measurements based on intensity modulation of light. Interferometric measurement methods. Gas spectroscopy. Distributed optical-fibre sensing. Passive and active fibre optic sensor networks.