Phytec FireWire-CAM-001, Руководство пользователя

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The Camera in Detail
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PHYTEC Messtechnik GmbH 2005 L-661d_1
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The image height H is calculated from the image width B based on
the following relationship:
B H
⋅ =
4
3
Please note that wide angle lenses will produce some edge
distortion, which can have a detrimental effect during image
capture or analysis. In this case try increasing the distance to the
object and set a larger focal length.
Reference points for selecting focal length:
Focal Length Lens Type
< 8mm Wide Angle
8 ... 16 mm Normal Range
> 16 mm Telephoto Lens
A selection of standard lens focal lengths can be found in our
catalog and on our web site. Please ask us about other available
focal lengths.
•
Resolution
How good will the picture resolution be for a given focal length?
This depends on the picture size (size of the screen window) and
the number of pixels the sensor has.
The FireWire-CAM-001 / -002 have a pixel count of 640 x
480 pixels (height x width).
You can now begin to determine the spacial resolution by dividing
the picture width in mm by the number of horizontal pixels (640)
(corresponding vertically).
Example:
You have a screen window that is 100 mm x 75 mm.
The maximum resolution that can be achieved is
100 mm : 640 = 0.15625 mm horizontal or
75 mm : 480 = 0.15625 mm vertical