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5-1
5
Image Sensor
This chapter provides an overview of the NI Smart Camera image sensors, field of view, spectral
response, partial scan mode, binning, gain, and hardware binarization. NI 1712/1732/1752
Smart Cameras use a VGA sensor. The NI 1754 Smart Camera uses an SXGA sensor. Refer to
Appendix A,
Specifications
, for information about the image sensors.
Field of View
The field of view is the area under inspection that will be imaged by the NI 17xx Smart Camera.
It is critical to ensure that the field of view of your system includes the object you want to
inspect.
To calculate the horizontal and vertical field of view (FOV) of your imaging system, use
Equation 5-1 and the specifications for the image sensor of your device, as listed in Appendix A,
Specifications
.
(5-1)
where
FOV
is the field of view in either the horizontal or vertical direction,
Pixel Pitch
measures the distance between the centers of adjacent pixels in
either the horizontal or vertical direction
1
,
Active Pixels
is the number of pixels in either the horizontal or vertical
direction,
Working Distance
is the distance from the front element (external glass) of
the lens to the object under inspection, and
Focal Length
measures how strongly a lens converges (focuses) or diverges
(diffuses) light.
1
Because NI 17xx Smart Camera sensors have square pixels,
pixel pitch
corresponds to the pixel size for
the appropriate sensor.
FOV
Pixel Pitch Active Pixels
×
Working Distance
×
Focal Length
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