Princeton Instruments PI-MAX4, Manual

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196 PI-MAX
®
4 System Manual Issue 9
13.2 Advantages of PI-MAX4: 1024i-RF
Classically, the experimenter wishing to use the RF technique had to collect and
interconnect and control various devices, including the ICCD itself, one or two RF sources,
two (usually) RF power amplifiers, a light source and a modulator. With the
PI-MAX4: 1024i-RF, the two RF sources and one RF amplifier are integrated in the ICCD.
This saves time, money, bench space and complexity. Coordination between the RF and the
camera actions is built in. The RF sources are direct digital synthesizers (DDSs) so the
generated RF is very precise in frequency and phase. The user still needs to provide a light
source capable of RF Modulation and possibly an RF amplifier matched to the needs of the
user’s light source. As many light sources are feasible, the PI-MAX4: 1024i-RF was
designed with a low level RF output for the user’s convenience. It can drive most
commercially available RF amplifiers.
The PI-MAX4: 1024i-RF is capable of executing RF sequences, much like the gate
sequences in the PI-MAX4. In fact, the RF sequence works in conjunction with the gate
sequence so that the RF is on during the time the PI-MAX4: 1024i-RF is capturing light,
and off during the reading of the CCD. For those using the homodyne technique, this makes
operation simple and convenient. Once the user selects a set of phase shifts and frequencies,
these can be loaded into the camera so that the camera can execute them at the highest rate,
limited only by the exposure time per image, the readout time, and the phosphor decay time.
The frequency and phase points can be in any order; they are not required to be in a strictly
ascending or descending order. This means that once the exposure of the sample starts, the
data will be measured in the minimum time, thereby minimizing sample degradation due to
the illumination.
NOTE:
The PI-MAX4: 1024i-RF does not support picosecond gating
nor MCP gating.
Figure 13-1: System Diagram: RF Operation
Computer
PI-MAX4: 1024i–RF
GigE
Trigger In
Power
Supply
Power
AUX Power
User RF Out
LASER
AUX I/O Cable
LASER
Modulator
100 V – 240 V
S
PECTROGRAPH
,
COOLANT CIRCULATOR
,
AND DRY NITROGEN TANK CONNECTIONS
ARE OPTIONAL AND ARE NOT ILLUSTRATED
.
4411-
0139
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