Basler L301kc, Installation And Operating Manual

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Operation and Features
Basler L301kc 3-3
DRAFT
3.2 Exposure Time Control Mode Basics
The
L301
kc
can operate under the control of an external trigger signal (ExSync) or can operate in
“free-run.” In free-run, the camera generates its own internal control signal and does not require
an ExSync signal.
3.2.1 ExSync Controlled Operation
In ExSync operation, the camera’s line rate and exposure time are controlled by an externally
generated (ExSync) signal (see Section
2.4 ).
When the camera is operating under the control of an ExSync signal, the length of the ExSync
signal period determines the camera’s line rate (see Section
2.4.1 ).
When the camera is operating with an ExSync signal, it has three modes of exposure time control
available: edge-controlled mode, level-controlled mode, and programmable mode.
• In ExSync , edge-controlled mode, the pixels are exposed and charge is accumulated over
the full period of the ExSync signal (rising edge to rising edge). The falling edge of the
ExSync signal is irrelevant.
The actual start of exposure is 1.76 µs later than the rise of the ExSync signal. The line is
read out and transferred on the rising edge of ExSync. (see Figure 3-3.)
Figure 3-3: ExSync, Edge-Controlled Mode
• In ExSync , level-controlled mode, the exposure time is determined by the time between the
falling edge of ExSync and the next rising edge. The pixels are exposed and charge is accu-
mulated only when ExSync is low.
The actual start of exposure is 0.050 µs later than the fall of the ExSync signal. The actual
length of the exposure time will be equal to the ExSync signal low time plus 1.76 µs. The line
is read out and transferred on the rising edge of the ExSync signal (see Figure 3-4).
Figure 3-4: ExSync, Level-controlled Mode