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3.8.5 Convergent Sensing Mode
The convergent sensing mode is a special variation of diffuse mode
photoelectric proximity sensing that uses additional optics to create a
small, intense, and well-defined image at a fixed distance from the
front surface of the sensor lens (Fig. 3.28). Convergent beam sensing
is the first choice for photoelectric sensing of transparent materials
that remain within a sensor’s depth of field. It is also called the fixed-
focus proximity mode.
3.8.6 Mechanical Convergence
In mechanical convergence (Fig. 3.29), an emitter and a receiver are sim-
ply angled toward a common point ahead of the sensor. Although less
FIGURE 3.28 Convergent sensing mode.
FIGURE 3.29 Mechanical convergence.
