Princeton 4411-0106 User Manual

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PIXIS System Manual 
Version 2.C 
 
Timing Modes  
Overview 
The basic PIXIS timing modes are Free Run {No Response}, External Sync {Readout 
Per Trigger}, and External Sync {Readout Per Trigger} with Continuous Cleans {Clean 
Until Trigger}.  These timing modes are combined with the Shutter options to provide the 
widest variety of timing modes for precision experiment synchronization.  
Mode 
Shutter Condition 
Free Run {No Response} 
Normal 
External Sync {Readout Per Trigger} 
Normal 
External Sync{Readout Per Trigger} 
PreOpen {Open Before Trigger} 
External Sync {Readout Per Trigger} with Continuous 
Cleans {Clean Until Trigger} 
Normal 
External Sync {Readout Per Trigger} with Continuous 
Cleans {Clean Until Trigger} 
PreOpen {Open Before Trigger} 
Table 3.  Camera Timing Modes   
The shutter options available include Normal, PreOpen {Open Before Trigger}, Disable 
Opened {Always Open} or Disable Closed {Always Closed}. Disable simply means that 
the shutter will not operate during the experiment. Disable closed {Always Closed} is 
useful for making dark charge measurements. PreOpen {Open Before Trigger}, available 
in the External Sync {Readout Per Trigger} and External Sync {Readout Per Trigger} 
with Continuous Cleans {Clean Until Trigger} modes, opens the shutter as soon as the 
PIXIS is ready to receive an External Sync pulse. This is required if the time between the 
External Sync pulse and the event is less than a few milliseconds, the time it takes the 
shutter to open.  
The shutter timing is shown in the timing diagrams that follow. Except for Free Run, 
where the modes of shutter operation are identical, both Normal and PreOpen lines are 
shown in the timing diagrams and flow chart.  
The timing diagrams are labeled indicating the exposure time (t
exp
), shutter compensation 
time (t
c
), and readout time (t
R
). These parameters are discussed in more detail in 
Chapter 5. Note that if there is no shutter selected in the software, the shutter 
compensation time (the time required to close a mechanical shutter) will be 
approximately 0 ms.