Andor Technology iXon Ultra 897 User Manual page 74

SETTING THE AQUISITION
The Exposure Time (in seconds) is the time during which the EMCCD collects
Exposure Time
light prior to readout. The system will default to a minimum Exposure Time should
you attempt to enter too low a value.
The system allows you use the EMCCD-chip at the heart of the detector in a Readout
number of ways to collect and read out data. See SECTION 4.5 – SETTING THE
ACQUISITION to view the various Readout Options and Binning Patterns available
with this system.
Frame transfer is a special acquisition mode that is only available if your system Frame Transfer
contains a Frame Transfer CCD, (FT CCD).
A FT CCD differs from a standard CCD in 2 ways. Firstly, a FT CCD contains 2
areas, of approximately equal size. The first area is the Image Area, which is
located at the top and farthest from the read-out register. This is the light sensitive
area of the CCD. The second section is the Storage Area, and is located between the
Image Area and the read-out register. This section is covered by an opaque mask,
usually a metal film, and hence is not sensitive to light.
The second way in which a FT CCD differs from a standard CCD is that the Image
and the Storage areas can be shifted independently of each other. These differences
allow a FT CCD to be operated in a unique mode where one image can be read out
will the next image is being acquired. It also allows a FT CCD to be used in
imaging mode without a shutter. Note: This is only applicable when the camera
is running in Accumulate or Kinetic mode.
For an explanation of the Gain principle of your iXon CCD, please see SECTION Gain
3 - INSIDE THE iXON CCD. In the Setup CCD Acquisition Dialog box, you can
control the level of Gain your iXon CCD is operating at. The Gain can be
increased from 0 (unity i.e. no gain) to a factory set level of 1000 times. The level
of Gain required can be entered manually in the control box, or you can use the
toggle keys to raise or lower the value to the required level.
Section 4 . 5
Page 74