Balluff MATRIX VISION mvBlueFOX Series, Техническое руководство

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1.19.2.5.2 Details of operation
The sensor uses following acquisition mode:
• rolling shutter ( ShutterMode = "ElectronicRollingShutter" )
With the rolling shutter the lines are exposed for the same duration, but at a slightly different point in time.
Note
Moving objects together with a rolling shutter can cause a shear in moving objects.
Furthermore, the sensor offers following operating modes:
• free running mode (Overlapping exposure and readout)
• snapshot mode (Sequential exposure and readout)
1.19.2.5.2.1 Free running mode
In free running mode, the sensor reaches its maximum frame rate. This is done by overlapping erase, exposure and
readout phase. The sensor timing in free running mode is fixed, so there is no control when to start an acquisition.
This mode is used with trigger mode
Continuous .
To calculate the maximum frames per second (FPS
max
) in free running mode you will need following formula:
FrameTime = (ImageHeight * (1650 / PixelClock)) + (25 * (1650 / PixelClock))
If exposure time is lower than frame time:
FPS_max = 1
----------------------
FrameTime
If exposure time is greater than frame time:
FPS_max = 1
------------------------
ExposureTime
1.19.2.5.2.2 Snapshot mode
In snapshot mode, the image acquisition process consists off several sequential phases:
1.19.2.5.2.3 Trigger
Snapshot mode starts with a trigger. This can be either a hardware or a software signal.
The following trigger modes are available:
Mode Description
Continuous Free running, no external trigger signal needed.
OnLowLevel As long as trigger signal is Low camera acquires images with own timing.
OnHighLevel As long as trigger signal is High camera acquires images with own timing.
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