Tellurite And Fluorotellurite Glasses For Active And Passive

2. Literature review; MDO 34
absorption of light, the development of light emitters and detectors which can handle high
modulation rates, and fabrication of very thin fibres which preserve the waveform of very
short light pulses. An essential development has been the cladding of fibres with a glass
of lower refractive index, which prevents the leakage of light from the surface.
Optical fibres are also useful in short communication links, especially where electrical
connections are undesirable. They also offer remarkable opportunities in computer
technology and laboratory instrumentation such as interferometers and a variety of
optical fibre sensors.
Total internal reflection
The transmission of light over long lengths of glass optical fibre, is possible by cladding a
core glass of refractive index nco, with a higher index glass of refractive index ncl. Fig.
(2.6) illustrates this principle.
90-φ
θ
φ
Core (nco)
Cladding (ncl)
Fig. (2.6): Total internal reflection of light along a glass optical fibre with a core of
refractive index nco, and cladding index ncl [35].