Teledyne Princeton Instruments PI-MAX 3, System Manual

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Chapter 14: Picosecond Option
The picosecond gating option for the PI-MAX3 allows optical gates down to less than
500 ps or to the lowest gate width the intensifier will support, whichever is greater. It
consists of a Picosecond Gating Board installed in the PI-MAX3 and additional
modifications to support the board.
The picosecond option can operate up to a 100 kHz repetition rate (the primary gate
generator goes to 1 MHz) and has a few nanoseconds’ larger insertion delay than the
primary gate generator.
REFERENCES:
Refer to Section 14.4, Repetition Rate Issues , on page 180,
for detailed information about achievable repetition rates.
The MONITOR BNC output operates differently in picosecond operation.
14.1 Activating Picosecond Operation
The activation of Picosecond depends on the data acquisition software being used:
• WinX/32
Automatically selects the picosecond gating board whenever the gate width is
set below 3 ns.
• LightField
The Picosecond Widths button will be added to the
SuperSYNCHRO Timing expander when a PI-MAX3 equipped with the
picosecond gating board is detected and loaded as an experiment device.
14.2 Gain and Gate Width
The apparent gain of the intensifier falls off as the gate width is reduced. Typically, at
the lower limit, the gain is less than 10% of the value observed at 50 ns.
• WinX/32
The software automatically selects the appropriate gate pulse generator to use
when the user selects a gate width.
The standard switch-over width is 3 ns.
• LightField
The user selects one of the available gate widths from the Picosecond Widths
drop down list and that width will be automatically entered in the Gate Width
field(s).
NOTE:
When Sequential Gating is active, the starting and ending
gate widths are the same: there are NO gate width
sequences. However, differing starting and ending gate
delays (swept delay) can be used with a constant gate width.