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3-2
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Chapter 3 NI Smart Camera Image Sensor
Figure 3-1 illustrates horizontal field of view and working distance.
Figure 3-1. Parameters of an Imaging System
For example, if the working distance of your imaging setup is 100 mm, and the focal length of
the lens is 8 mm, then the field of view in the horizontal direction of a smart camera using the
VGA sensor in full scan mode is
(3-2)
Similarly, the field of view in the vertical direction is
(3-3)
Based on the result of Equations 3-2 and/or 3-3, you can see that you might need to adjust the
various parameters in the FOV equation until you achieve the right combination of components
that match your inspection needs. This might include increasing your working distance,
choosing a lens with a shorter focal length, or changing to a high resolution camera.
1 Horizontal Imaging Width 2 Working Distance 3 Horizontal Field of View
3
2
1
FOV
horizontal
0.0074 mm 640 × 100 mm ×
8 mm
---------------------------------------------------------------------
59.2 mm
= =
FOV
vertical
0.0074 mm 480 × 100 mm ×
8 mm
---------------------------------------------------------------------
44.4 mm
= =