Page 209 - Sensors and Control Systems in Manufacturing

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Cha p te r

FIGURE 3.48 T h ree
Prism tip for liquid
sensing.

3.14 Flexibility of Fiber Optics
The power of fiber optics is further shown in the flexibility of its sys-
tem configurations. A master industrial terminal (Fig. 3.49) can access
any of a number of remote processors. The flexibility of switching,
distance capability, and noise immunity of such a system are its pri-
mary advantages.
Figure 3.50 illustrates a passive optical coupler with a two-way
fiber-optic link communicating over a single fiber through an on-axis
rotary joint. Such a system allows a simple uninterrupted communi-
cation link through rotary tables or other rotating machinery. This is
a true challenge for high-data-rate communication in a wire system.

3.14.1 Fiber-Optic Terminations
Optical fibers are becoming increasingly easier to terminate as rapid
advances in termination technology continue to be made. Several
manufacturers have connector systems that require no polishing of
the fiber end, long a major objection in fiber optics. Products that
eliminate epoxy adhesives are also being developed. Field installa-
tion times now typically average less than ten minutes for large-core
fibers (100 and 200 μm) with losses in the 1- to 3-dB range. Further,