Basler A640F, Руководство пользователя

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Basic Operation & Standard Features
BASLER A640
f
3-13
DRAFT
Determining whether your camera will operate with overlapped or non-overlapped exposures is
not a matter of writing to a register or switching a setting on or off. Rather the way that you operate
the camera will determine whether the exposures are overlapped or not overlapped. If we define
the “Frame Period” as the time from the start of exposure for one image capture to the start of
exposure for the next image capture, then:
• Exposure will overlap when: Frame Period
≤
Exposure Time + Readout Time
• Exposure will not overlap when: Frame Period > Exposure Time + Readout Time
You can calculate the readout time for a captured image by using the formula on page 3-17 .
Guidelines for Overlapped Operation
If you will be operating the camera with overlapped exposures, there are two very important
guidelines to keep in mind:
• You must not begin the exposure of a new frame while the exposure of the previous frame is
in progress.
• You must not end the exposure of a new frame until readout of the previous frame is com-
plete.
If either of these guidelines is violated, the camera will produce unacceptable images or may stop
capturing images and require a reset.
When you are operating the camera with overlapped exposures, you could use the camera’s
shutter setting and the timing numbers shown in Section
3.2.10 to calculate when it is safe to begin
and end each exposure. However, there is a much more convenient way to know when it safe to
begin and end overlapped exposures.
A640
f
cameras supply a “Trigger Ready” signal that is
specifically designed to let you perform overlapped exposures safely and efficiently. For more
information on using the Trigger Ready signal, please see Section
3.2.8 .