Operation 25
RM/TM-4200GE Series
3.3.4
Asynchronous Programmable Exposure Mode
In Asynchronous Programmable Exposure Mode, when an external trigger is applied, the exposure starts after
one discharge signal (Vsub), which happens after the trigger’s active edge is off. Because the discharge signal
(Vsub) synchronizes with LDV in this mode, there is a maximum one video line of jitter between the trigger
active edges to discharge signals (Vsub) off. In this mode, the exposure time from 0 video line to 2079 video
lines can be controlled via software in one video line steps. In this mode, the minimum exposure time is equal
to 0 video line plus overhead: the maximum exposure time is equal to 2079 video lines plus overhead. Where
the specified exposure time is n video lines, the real exposure time is equal to:
•
If the exposure time is less than one frame time, the maximum trigger frequency is equal to 1/1 frame
time.
•
If the exposure time is longer than one frame time, the maximum trigger frequency is equal to 1/
exposure time.
•
The minimum active period of the external trigger is 5
µ s.
Figure 17.
Asynchronous Programmable External Trigger