Basler Vision Technologies Sprint Series, Руководство пользователя

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Exposure Start and Exposure Time Control
74 Basler sprint Mono Cameras
4.3 Maximum Allowed Line Rate /
Minimum Line Period
The information in this section is intended to give you a comprehensive understanding about the
factors that influence the maximum allowed line rate and how those factors interact.
In general, the maximum allowed line acquisition rate can be limited by four factors:
„
The exposure time for the acquired lines. If you use long exposure times, you can acquire
fewer lines per second.
„
The amount of time it takes to read an acquired line out of the imaging sensor and into the
camera’s line buffer. This time can vary depending on the length of the area of interest (AOI)
for the acquired lines. Smaller AOIs can take less time to read out.
„
The amount of time that it takes to process the pixels before they are ready for transmission.
This time varies by camera model.
„
The amount of time it takes to transmit the pixel data for an acquired line from the camera to
the host PC. This time can vary depending on the length of the area of interest (AOI) for the
acquired lines. Smaller AOIs take less time to transmit.
For information about the camera settings to obtain the maximum specified line rate of the camera,
see Section 4.3.4 on
page 82 .
To determine the maximum allowed line acquisition rate with your current camera settings, you
must calculate a result for the four formulas that appear below. The formula that returns the lowest
value will determine the maximum allowed line rate with the current settings. (In other words, the
factor that restricts the line rate the most will determine the maximum allowed line capture rate.)
Note
When operating a camera in dual line acquisition mode (see page 39 ), the
maximum allowed line acquisition rate may be lower than suggested by the
formulas given below.
Knowing the maximum allowed line acquisition rate or the minimum line period
will be particularly important when you want to operate the camera under the
control of an external sync signal (see
page 33 ).
To determine the maximum allowed line acquisition rate, check the Line Period
parameter in the Exposure parameter group of the CCT+ or check the absolute
min field of the Line Period CSR (see
page 171 ) and use the line period value
to calculate the maximum allowed line acquisition rate.
Check the line period value before setting the camera to operate under the
control of an external sync signal. The line period value will else not be
indicated.