User's Manual

Preco Electronics, Inc.
415 N. Maple Grove, Boise, ID 83704 [phone] Copyright 2002 Page 3 of 10
370-871-1B
energy that strikes an object reflects a certain amount of this energy back to the PreView
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sensor. This returned energy is measured to determine an object’s distance.
The amount of energy returned is based on a few factors:
Size – a larger object usually reflects more energy than a smaller object.
Distance – the farther away an object is, the less energy is returned.
Composition – a metal object reflects more energy than a non-metallic object. A metallic
object at the edge of the zone will be detected, where a wood object may not.
Scattering – a solid object reflects more energy that a non-solid object such as wood,
gravel, bushes, etc.
Angle – an object perpendicular to the sensor will reflect more energy than an object at
an angle. See below for a detailed explanation.
Figure 1. Object Reflection
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