Balluff MATRIX VISION mvBlueFOX Series, Technical Manual

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1.18.8.1 Using external trigger with CMOS sensors
1.18.8.1.1 Scenario The CMOS sensors used in mvBlueFOX cameras support the following trigger modes:
• Continuous
• OnDemand (software trigger)
•
OnLowLevel
•
OnHighLevel
• OnHighExpose (only with mvBlueFOX-[Model]205 (5.0 Mpix [2592 x 1944]) (p. 215 ))
If an external trigger signal occurs (e.g. high), the sensor will start to expose and readout one image. Now, if the
trigger signal is still high, the sensor will start to expose and readout the next image (see Figure 1, upper part). This
will lead to an acquisition just like using continuous trigger.
Figure 1: External Trigger with CMOS sensors
• t
trig
= Time from trigger (internal or external) to integration start.
If you want to avoid this effect, you have to adjust the trigger signal. As you can see in Figure 1 (lower part), the
possible period has to be smaller than the time an image will need (t
expose
+ t
readout
).
1.18.8.1.2 Example
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