Varex Imaging 2315NDT, Руководство пользователя

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USER
MANUAL
36 www.vareximaging.com
2315NDT v2 CMOS X-ray Detector User Manual
The Exposure modes for multiple images acquisition with one trigger (Sequence, Frame-rate and
Pre-programmed) shown in “Readout Mode ‘Continuous’” on page 26 are not available in Idle
mode as the exposure window is determined by the distance of the trigger sent and not via
register. A trigger is needed for each image acquisition.
19.2.1 Idle Readout – Software Trigger
In Software Trigger, the trigger is sent by the software (SCap or API function). In SCap, this
source is selected using Configuration — External Trigger — Software Trigger and following the
sequence below, see Figure 18 . Values are shown in Table 15 .
1
Before an exposure, the detector is waiting without reading out dark frames from the sensor.
2
The user activates an external trigger signal (T
WSI
).
3
When the detector receives the trigger, it will start reading out the sensor and the SyncOut 1
and SyncOut 2 signals will change their status.
4
The first image will contain all the dark currents accumulated from the detector since it was
powered on, so it will likely be noisier or even saturated and it will need to be discarded.
5
After T
R/O
the detector finishes the acquisition on the first (discarded) image and the
SyncOut signals both go back to their initial status.
Table 15 Software Trigger values for Idle readout
Symbol Description Value Notes
T
WSI
Software trigger/SyncIn
duration Minimum = 200 µs
N/A
T
R/O
Detector frame readout
time See Frame readout
times in
Table 13
on page 29
.
N/A
T
EW
Detector exposure
windows (not including
the frame readout T
R/O
Table 13 on page 29
)
Minimum = 200 µs T
EW
is the frame exposure window (not
including the readout, see
Table 13 on
page 29
). In Idle mode, it is determined by
the time difference between trigger. 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 Set by the user.
Maximum equal to
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 specified
T
EW
. See Dexela X-ray Detector Software Manual for more information.