Sensors help microprocessor-based systems find their bearings. Where would embedded systems be without them? Sensors provide the windows through which microprocessor-based systems can observe their ...

What's behind the target can make a tremendous difference in how well reflective sensors do their job. Consider a photoelectric sensor operating in simple diffused mode (i.e., as a proximity sensor).

Figure 1a shows a slotted optical switch. An LED is mounted in a plastic housing, facing a phototransistor, but separated by a gap. If something moves into the gap, it blocks the light path between ...