BOBCAT Hardware User’s Manual
Imperx, Inc.
Rev. 1.0
6421 Congress Ave.
5/4/2010
Boca Raton, FL 33487
+1 (561) 989-0006
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TRIGGER
DATA
TRANSFER
EXPOSURE
STROBE
DATA
Exp.1
Exp.2
Exp.3
Exp.4
Exp.5
Trg.1
Trg.2
Trg.3
Trg.4
Trg.5
DATA
OUTPUT
Figure 2.17 – Frame accumulation triggering
E.
Asynchronous Triggering
When the Asynchronous triggering mode is enabled, the camera is free running (no
horizontal and vertical flushing prior to trigger). Upon receiving the external trigger
signal, the current CCD timing stops, all camera lines are rapidly flushed, and a new
frame starts – Figure 2.18. This completes the current trigger cycle, the camera free
running and waits for the next trigger pulse. In this mode the camera exposure can
be controlled with the internal shutter or with the trigger pulse width. The time
required for rapid line flush (all charges stored in the vertical registers are cleared)
is camera dependent and if the camera is triggered via CC line, and the camera
exposure is determined by the duration of the CC pulse, the CC pulse duration must
be longer than the rapid flush time, as shown below.
TRIGGER
EXPOSURE
DATA
DATA
VCCD
DUMP
DATA
DATA
DATA
SHUTTER
Figure 2.18 – Asynchronous triggering
