Andor Technology iXon3 Series - Triggering Options in Non-Frame Transfer (NFT) Mode; Internal (NFT)

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iXon 3
Features & Functionality
3.5.2 - Triggering options in Non-Frame Transfer (NFT) mode
3.5.2.1 - Internal (NFT)
When the camera is idle, i.e. not actively capturing images, it is repeatedly running the Idle Keep Clean Cycle. When
the Start command is received from the PC, the camera will complete the current keep clean cycle and then perform
sufcient vertical shifts to ensure the Image and Storage regions are completely free of charge. The camera is now ready
to start the real exposure sequence.
The timing sequence is illustrated in the gure below. During the exposure the FIRE output will be high and there will
be no vertical clocking. However, the horizontal register will keep running. At the completion of the exposure time the
FIRE pulse will go low and the Image area of the CCD will be shifted into the Storage area. As the acquired signal is now
safely placed in the masked off region of the CCD light still falling on the CCD will not contaminate the acquired image
whileitisbeingreadout.OncompletionofthereadoutthecamerawillperformtheInternal keep clean cycle until
the user specied cycle time has elapsed. This process is continued until the complete series of acquisitions has taken
place.
Figure 32: Internal Trigger in Non-Frame Transfer mode