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FIGURE. 3.43 Fiber Optics in Sensors and Contr ol Systems 167
Refl ective mode
bifurcate fi ber optics.

HEMISPHERICAL RANDOM PCS PAIR
FIGURE 3.44 Bundle construction.

Typical bundle construction in a bifurcate employs one of two
arrangements of individual fibers. The sending and receiving fibers
are arranged either randomly or hemispherically (Fig. 3.44). As a
practical matter, there is little, if any, noticeable impact on the perfor-
mance of a photoelectric system in any of the key parameters such as
sensitivity and scan range.
Application areas for bundle probes include counting, break
detection, shaft rotation, and displacement/proximity sensing.

3.13.2 Bundle Design Considerations
Microscopic fiber flaws (Fig. 3.45) such as impurities, bubbles, voids,
material absorption centers, and material density variations all dimin-
ish the ability of rays of light to propagate down the fiber, causing a

FIGURE 3.45 Microscopic fi ber fl aws.