Trigger Port
This is very useful for surveillance and machine vision applications. For example a light barrier can
simultaneously send out a trigger pulse to the EYE-12 and to a harddisc recorder when someone enters a
room. Most recording devices can not start recording in a fraction of a second. If the camera would output a
live image, a later image would be recorded, which does not show the exact situation anymore. But as the
trigger function freezes the image output by the EYE-12, the exact image is recorded.
NORMAL MODE (Free Running)
In normal mode (Trigger is de-activated by default) the camera generates live images with a frame rate of
30 fps. The duration of exposure can be changed in the on-screen menu with the shutter setting. The
sampling time is controlled by the camera electronic and can not be changed.
TRIGGER MODE
The EYE-12 offers a trigger input to determine the moment of image readout.
When the TRIGGER-function is activated, the sampling time is controlled by receiving trigger-pulses
(positive or negative edge, selectable in the on-screen menu -
see page 10
).
The image is processed 1/30s after the camera receives the trigger pulse.
The exposure time is variable and determined by the shutter time. However, the end of exposure is always
1/30s after the trigger pulse. The start of exposure is also determined by the shutter time (Shutter is
adjustable in the on-screen menu).
3.3 - 40 Vss
Trigger_in
Exposure
Image readout
t
= Exposure time
exp
1/30s
ready for next trigger
t = frame rate
ro
1/30s
1/30s
Please note:
The maximum trigger frequency is 15Hz (2x 1/30s). This will result in a maximum frame rate of 15fps.
Please note:
When switching on the Trigger mode in the on-screen menu, the EYE-12 freezes the current image. The
next image will be processed when the EYE-12 receives a trigger pulse.
Please note:
When the time between the trigger pulses are too short, the message "Trigger Overrun" will appear on the
screen. Decrease the trigger pulse frequency to rectify this.
13
Example with positive trigger edge
