National Instruments ISC-1762, Руководство пользователя

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3-1
3
NI Smart Camera 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 1722/1742/1762
Smart Cameras use a VGA sensor. NI 1744/1764 Smart Cameras use an SXGA sensor. Refer to
Appendix A,
Specifications
, for information about your smart camera image sensor.
Field of View
The field of view is the area under inspection that will be imaged by the NI 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 3-1 and the specifications for the image sensor of your smart camera, as listed in
Appendix A,
Specifications
.
(3-1)
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,
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.
FOV
Pixel Pitch Active Pixels
×
Working Distance
×
Focal Length ----------------------------------------------------------------------------------------------------------------- =