RMV Operations Manual Revision Copyright illunis LLC, 2014
Page 60
4.2.7: Exposure:Trigger Modes
Trigger Substrate Pulse Delay
The trigger substrate delay (TSUBD) pulse is
useful in applications where a very powerful flash is
used. Because a very bright flash will overpower the
VCCD light shield and create unwanted smear the
TSUBD is used to delay the photo diode erasure
pulse (Substrate Pulse).
If the VCCD is clocked during a very bright
flash then the sensor will contain smear within the
VCCD. The TSUBD allows for the VCCD flush to
stop before the flash thus preventing image smear
(from the flash).
Serial Commands
Target
Index
Command
R/W
Description
02
0B
SUB Delay
R/W
Default = 0x0001
02
0C
Triggered VCCD on
W
VCCD clocks during triggered exposure
02
0D
Triggered VCCD off
W
No VCCD clocks during triggered exposure
Quick FAQ’s:
►Use the TSUBD with applications that have very
tight timing and very bright flash exposures.
►The TSUBD time units are the same as TPD.
►The substrate pulse is used to erase the photo
diodes for the beginning of exposure.
►The default for normal operation of TSUBD is a
register value of 0x0001
►TheTSUBD must be zero for TME mode to
function.
Normal Triggered Image
This scope plot shows a normal triggered im-
age where exposure starts at the trigger and
ends at the interline transfer. The VCCD is
clocked throughout the exposure to minimize
dark current buildup in the VCCD.
Yellow = Trigger, Blue = VCCD Clocks, Red = Exposure strobe, Green = FVAL
Triggered Image with VCCD off and TSUBD
This scope plot shows a triggered image where
exposure is delayed from the trigger by the
TSUBD register value (and ends at the interline
transfer). The VCCD is stopped throughout the
exposure to eliminate smear of the image in
the VCCD.
Yellow = Trigger, Blue = VCCD Clocks, Red = Exposure strobe, Green = FVAL
