Chapter 5 Operation; Introduction; Figure 16. Block Diagram Of Proem+ System - Princeton Instruments ProEM+ EMCCD User Manual

Operation

Introduction

Once the ProEM+ camera has been installed as explained
in the preceding chapters, operation of the camera is
straightforward. In most applications you simply
establish optimum performance using the Focus
{Preview} mode (in WinX, for example), set the
target camera temperature, wait until the
temperature has stabilized, and then do actual data
acquisition in the Acquire mode. Additional
considerations regarding experiment setup and
equipment configuration are addressed in the
software manual.
During data acquisition, the CCD array is exposed
to a source and charge accumulates in the pixels.
After the defined exposure time, the accumulated
signal is readout of the array, digitized, and then
transferred to the host computer. Upon data transfer,
the data are displayed and/or stored via the
application software. This sequence is illustrated by
the block diagram shown in Figure 16.
Whether or not the data are displayed and/or stored
depends on the data collection operation that has
been selected in the application software.
In WinX and LightField, the data collection
operations use the Experiment Setup parameters to
establish the exposure time (the period when signal of
interest is allowed to accumulate on the CCD). Focus {Preview} is more likely to be
used in setting up the system (see the "First Light" discussions) and Acquire is then
used for the collection and storage of data. Briefly:

In Focus {Preview} mode, the number of frames is ignored. A single frame is
acquired and displayed, another frame is acquired and overwrites the currently
displayed data, and so on until Stop is selected. In WinX, the last frame acquired
before Stop is selected can be stored; in LightField, this frame cannot be stored.
Focus {Preview} mode is particularly convenient for familiarization and setting up.
For ease in focusing, the screen refresh rate should be as rapid as possible, achieved
by operating with axes and cross-sections off, and with Zoom 1:1 selected.

In Acquire mode, every frame of data collected can be automatically stored (the
completed dataset may include multiple frames with one or more accumulations).
This mode would ordinarily be selected during actual data collection. One limitation
of Acquire mode operation is that if data acquisition continues at too fast a rate for it
Chapter 5
Figure 16. Block Diagram of
ProEM+ System
39