Frame Transfer/Full Frame Timing {Trigger Response} Modes And Shutter Control {Shutter Mode; Overview; Ext Sync Trigger Input; Free Run {No Response - Princeton Instruments ProEM+ EMCCD User Manual

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Frame Transfer/Full Frame Timing {Trigger Response} Modes
and Shutter Control {Shutter Mode}

Overview

The basic ProEM+ timing {Trigger Response} modes for Frame Transfer and Full Frame
operations are Free Run { No Response }, External Sync { Readout Per Trigger },
Bulb Trigger { Expose During Trigger Pulse } and Trigger Start { Start On Single
Trigger }. These modes are combined with the Shutter Control {Shutter Mode} options
to provide the widest variety of modes for precision experiment synchronization. The
shutter options available for Frame Transfer and Full Frame operations are Normal,
Disabled Opened {Always Open}, and Disabled Closed {Always Closed}.
Disabled simply means that the shutter will not operate during the experiment. Disabled
closed is useful for making dark charge measurements. PreOpen {Open Before Trigger},
available in the External Sync and External Sync with Continuous Cleans {Clean Until
Trigger} modes, opens the shutter as soon as the ProEM+ 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 {No
Response}, where the modes of shutter operation are identical, both Normal and PreOpen
{Open Before Trigger} lines are shown in the timing diagrams and flow chart.

EXT SYNC Trigger Input

The selected Timing Mode {Trigger Response}
determines how the camera will respond to an
External Sync pulse that is input at the EXT
SYNC connector on the rear of the camera.
Things to keep in mind when setting up the
External Sync pulse input are:
Pulse Height: 0 to +3.3V logic levels (TTL-
Pulse Width (trigger edge frequency): The
EXT SYNC Connector Impedance: High
Trigger Edge {Trigger Determined By}:

Free Run {No Response}

In this mode, there is no external triggering {or the camera is ignoring external triggers}
and all settings are read from the setup parameters, making the duration of each exposure
time constant and the interval times between exposures constant (see Figure 40).
ProEM
compatible).
time between trigger edges.
impedance.
rising or falling edge must be indicated on
the Experiment Setup|Timing tab { Trigger expander}.
®
+ System Manual

Figure 39. Rear of ProEM+ Camera

Version 1.B