Plastic optical fibres

Optical fibres composed of plastics are also transparent in the visible spectral region but optical losses reach 102 - 103 dB/km13. Their refractive index varies from 1.35 to 1.6 depending on the kind of polymer used (e.g. polymethymethacrylate PMMA -1.49). The chemical resistance is much worse than that of silica fibres and thermal stability is incomparable. On the other hand, low temperature processes of plastic fibre preparation allow us mix the starting polymer with organic dyes which enables the production of luminescent fibres suitable e.g. for fluorescence-based sensing13. 

The other sensor makes use of two dyes, bromophenol blue (BPB) and thymol blue (TB), to cover the range of interest26. The chromophores, immobilised on controlled pore glasses, are fixed at the end of plastic optical fibres. The distal end of the fibres is then heated and the CPGs form a very thin pH-sensitive layer on the fibre tips. The probe has four fibres (two for each chromophore) and its sketch is shown in Figure 5. A Teflon diffuse... 

Falciai R., Baldini F., Cosi F., Bechi P., Pucciani F., Bile enterogastric reflux sensor using plastic optical fibres, Fiber and Integr. Opt. 1993 12 215. 

In the manufacture of plastics in forms such as minute particles, special illumination is needed—typically, the combination of a halogen lamp with optical fibres. Recently, equipment of high illuminating capacity using a short arc has been marketed for work of this nature. 

The main disadvantage is that at least one of the substrates must be transparent to the radiation initiating cure. This requirement prevents also the filling or pigmenting of such materials. Nevertheless, many applications are being developed—bonding glass, transparent plastics, jewellery, and optical fibres. 

K. Kuriki, Y. Koike, and Y. Okamoto, Chem. Rev., 2002, 102, 2347 (plastic optical fibre lasers and... 

Marcou, J. and Club des fibres optiques plastiques. (1997). Plastic optical fibres practical applications. Chichester New York, Paris, John Wiley Masson. 

Figure 14.30 The structure of an optical fibre. The fibre is made of glass with a higher refractive index - the core - and glass of a slightly lower refractive index -the cladding. The fibre is covered in a plastic coating to...

A NIR spectrometer system has been described based on optical fibres for absorption and reflexion measurements, an AOTF and a transputer system. It is able to detect 1,000 spectra per second and to identify 20 pieces per second (209). The identification system was implemented and tested for a real-world application of plastic identification in municipal solid waste. 

Cellulose thin films for documents and book recovery fibres (including optical) biodegradable plastics oriented templates liquid crystal displays luminescent materials fuel cell membranes drag delivery stents covering ophthalmic, cardiovascular and neurological prostheses bulletproof materials... 

Optical fibre cables are communication cables made from optical-quality plastic, the same material from which spectacle lenses are manufactured. The energy Is transferred down the cable as digital pulses of laser light, as against current flowing down a copper conductor In electrical Installation terms. 

Optical fibre cables are communication cables made from optical-quality plastic, the same material from which spectacle lenses are manufactured. 

Optical fibre cables are communication cables made from optical-quality plastic, the same material from which spectacle lenses are manufactured. The energy is transferred down the cable as digital pulses of laser light as against current flowing down a copper conductor in electrical installation terms. The light pulses stay within the fibre-optic cable because of a scientific principle known as total internal refraction which means that the laser light bounces down the cable and when it strikes the outer wall it is always deflected inwards and, therefore, does not escape out of the cable, as shown in Fig. 14.46. 

For the measurements in the field of detonation, optoelectronic single-grade monofilament optical fibres of a relatively low attenuation factor, 1 mm core diameter and 2.2 mm outside diameter of the black plastic jacket, be used. 

In spite of the fact that most textile-based sensing mechanisms rest on electrical signals and make use of electroconductive textiles, also optical sensing methods are applied in smart textiles. Therefore, optical fibres are employed, and in most cases plastic optical fibres (POF) because they are less brittle and more compatible with textile materials. 

It is well known that optical fibres are commonly used in communication, to carry light-coded information from one point to another. They are classically made out of transparent plastic or glass material, of diameter from 5 to 1000 pm, and allow transmitting the introduced light energy with minimum losses to their distal end. In fact, if... 

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