USER
MANUAL
28
www.vareximaging.com
2315NDT v2 CMOS X-ray Detector User Manual
1
Before an exposure, the detector is continuously reading dark frames from the sensor to
avoid the accumulation of dark current in the pixels. A frame readout lasts a time T
R/O
.
2
The user sends the trigger signal from the software to the detector (T
WSI
).
3
When the detector receives the trigger, the SyncOut 1 signal changes its status and the sensor
finishes the ongoing frame readout (T
R
).
4
After T
R
the detector enters the exposure window (T
EW
) and the Sync Out 2 level changes.
5
At the same time, the detector starts accumulating the image on the sensor.
6
The user can configure the X-ray to be active during T
EW
.
7
After the detector’s programmed exposure window T
EW
, the frame is read out and
transmitted to the PC. SyncOuts levels go back to their initial values.
8
The detector resumes the dark frame readout cycles until the next software trigger.
Figure 8
Continuous readout - Software Trigger Schematic
T
EW
Detector exposure windows
(not including the frame
readout T
R/O
-
)
Minimum = 200 µs
SyncOut pulse width. Due to
latency in the optocoupler, a
pulse sent to the output has an
additional 100
µs duration.
T
XRAY
Duration of the X-ray pulse
Minimum = Set by the user.
Maximum = T
EW
.
N/A
Note
: The ‘Exposure time’ the user sets in the API must be obtained by the sum of T
R
and the wanted
T
EW
. See the
Dexela X-ray Detector Software Manual
for more information.
Table 12
Software Trigger Values for continuous readout.
