Matrix Vision mvBlueFOX, Техническое руководство, Страница: 168 / 255

19.4 Working with HDR (High Dynamic Range Control) 161
• 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
).
19.3.1.2 Example
19.3.1.2.1 External synchronized image acquisition (high active)
Note
Using mvBlueFOX-MLC or mvBlueFOX-IGC, you have to select DigIn0 as the trigger source, because the
camera has only one opto-coupled input. Only the TTL model of the mvBlueFOX-MLC has two I/O's.
• Trigger modes
–
OnHighLevel:
The high level of the trigger has to be shorter than the frame time. In this case, the sensor will make
one image exactly. If the high time is longer, there will be images with the possible frequency of the
sensor as long as the high level takes. The first image will start with the low-high edge of the signal.
The integration time of the exposure register will be used.
– OnLowLevel:
The first image will start with the high-low edge of the signal.
– OnHighExpose
This mode is like OnHighLevel , however, the exposure time is used like the high time of the signal.
See also
Block diagrams with example circuits of the opto-isolated digital inputs and outputs can be found in
Dimen-
sions and connectors (p. 59).
19.4 Working with HDR (High Dynamic Range Control)
There are several use cases concerning High Dynamic Range Control:
19.4.1 Adjusting sensor -x00w
19.4.1.1 Introduction
The HDR (High Dynamic Range) mode of the sensor -x00w increases the usable contrast range. This is achieved
by dividing the integration time in two or three phases. The exposure time proportion of the three phases can be set
independently. Furthermore, it can be set, how much signal of each phase is charged.
MATRIX VISION GmbH