Princeton 4411-0106 User Manual

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Chapter 5 
Operation 
Introduction 
Once the PIXIS 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 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 is displayed and/or 
stored via the application software. This sequence is 
illustrated by the block diagram shown in Figure 12.  
Whether or not the data is 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 
to be stored, data overflow may occur. In WinX, this could only happen in Fast Mode 
operation.  
Figure 12.  Block Diagram of  
PIXIS System