Specifications

Version 1.1 rev Jan 2013
Page 82
iXon Ultra
, Features and Functionality
3.9.1 - Cropped Sensor Mode Frame Rates
In biological imaging, Cropped Sensor Mode can be successfully used to enhance performance, and throughput, in
super-resolution ‘nanoscopic’ applications including STORM and PALMIRA.
Imaging frame rates exceeding 1,000/s can be achieved with a sufciently small crop area. A series of measurements
carried out on the Andor iXon Ultra 897 EMCCD camera, has demonstrated that Cropped Sensor Mode, in conjunction
with binning, pushed the speed beyond 4,000 frames per second.
The Imaging frame rate potential of the Andor iXon Ultra 897 EMCCD camera under conditions of Cropped Sensor
Mode readout are shown in the Table below:
Crop Mode
BINNING 256 x 256 128 x 128 64 x 64 32 x 32 512 x 100 512 x 32 512 x 1
1 x 1 111 595 1,433 3,534 282 858 11,074
2 x 2 215 1,085 2,433 5,328 539 1,589 -
3 x 3 402 1,803 3,578 6,579 982 2,682 -
4 x 4 699 2,532 4,211 6,146 - 3,727 -
Standard Mode
BINNING 512 x 512 256 x 256 128 x 128 64 x 64 512 x 100 512 x 32 512 x 1
1 x 1 55.8 110 212 397 266 704 2,778
2 x 2 109 210 392 694 485 1,136 -
4 x 4 206 385 680 1,099 813 1,587 -
8 x 8 369 645 1,042 1,493 - 1,923 -
EMCCD-based adaptive optics, for which smaller format EMCCD sensors are often used, can benet from cropped
sensor readout. EMCCDs can be exibly optimized in cropped mode to exceed 2,000 fps. Use of cropped sensor mode
opens new possibilities for very fast adaptive optics imaging, enabling the users to reach into several thousands of
frames per second.
There is also potential to use cropped EMCCDs for multi-spectral uorescence confocal scanning, as an alternative
to the arrays of PMTs that have traditionally been used in this approach. The > 90% quantum efciency of the back-
illuminated sensor, single photon sensitivity, array architecture and rapid pixel readout speed can be exploited to
markedly improve this approach. The laser dwell-time should be set to coincide with the time to expose and readout a
short row of approximately 32 pixels - sufcient spectral channels to yield effective un-mixing of several known emitting
dyes, resulting in a data cube of 512 x 512 x 32 (spectral), and taking less than 1 second to generate. There is a clear
sensitivity advantage of EMCCD pixels over the usually employed PMT-technology, which is circa 5-fold in the blue-
green and up to tenfold in the red wavelengths.