Teledyne Princeton Instruments IsoPlane 81, Руководство пользователя

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Appendix E: Timing Generator
The IsoPlane 81 includes a built-in general purpose Timing Generator (TG) with 10 ns
resolution. The TG is often used in conjunction with the IsoPlane 81 laser accessory, but
is not limited to the laser. It can control the timing of any two devices that support TTL-
level timing inputs. The timing generator provides two output pulses. In a pump-probe
experiment, for example, the first pulse could time the pump flash and the second
could time the probe laser pulse.
The user can easily set the width and delay of each pulse from the starting point, T
0
.
LightField provides a virtual oscilloscope display so the user can view the timing
graphically. The timing generator has access to internal signals of the IsoPlane 81, so
that the pulses can easily be coordinated with the exposure and readout of the IsoPlane
81 CCD. It also has flexible trigger modes, so the user can easily synchronize it to an
experiment. Furthermore, the user can set the TG to provide multiple (or single) sets of
pulses in response to a trigger.
E.1 T
0
T
0
is the time from which the TG times its pulses. T
0
only exists inside the TG and is not
directly accessible to the user. When using external trigger, T
0
is a few nanoseconds
after the trigger pulse (the interval from trigger to T
0
is the sum of a few propagation
delays in electronic components and the time for the trigger to travel from the
connector to the TG). When the TG is being timed from the camera operation, T
0
is the
time when the TG receives the “go ahead” signal from the camera. In many cases, the
delay from trigger to T
0
is small enough to ignore.
E.2 Configuring the Timing Generator in LightField
Open the Camera Timing Dashboard and select either Repetitive or Sequential mode.
Repetitive mode is discussed first; sequential mode is a little more complex.
E.2.1 Repetitive Timing Mode
LightField labels the two pulses Gate and AUX Output. These outputs and the Trigger
input are available on the Auxiliary Cable (TPI part 6050-0752).
CAUTION!
!
Exercise caution when plugging the AUX Cable into the
rectangular connector adjacent to the USB connector. The
connector is delicate. Be sure to squeeze the two finger
grips on the sides of the connector when plugging it in. This
releases the locking barbs. When plugged in, the connector
will be locked in.
The AUX cable has three coaxial cables that terminate in three color-coded BNC
connectors:
• Black
This is the external trigger input.
• Red