Princeton Instruments ProEM+ EMCCD, User Manual

Page: 69 / 152

68 ProEM
®
+ System Manual Version 1.B
Figure 33. EMCCD Array Structure
WinX and LightField allow you to specify the type of readout (full frame or binned), the
output amplifier, and the gain (the number of electrons required to generate an ADU).
Dual-Readout Port Operation
The ProEM+: 512B/BK, 1024B, 1600
(2)
, and 1600
(4)
models are configured with
software-selectable dual-readout amplifiers, also referred to as "ports", shown in
Figure 33. The two amplifiers are listed below.
Port #1: Multiplication Gain
Port #2: Low Noise (Normal CCD)
If your camera is configured with two readout amplifiers (ports), the software
automatically allows port selection.
Note:
As the user interface may be different, please refer to your software manual for
specific information on readout amplifier/port selection.
1. Multiplication Gain {Electron Multiplied}: When this port is selected, the EM
gain value can be entered on the
Experiment Setup|Main
tab {
Analog to
Digital Conversion expander}. Since the multiplication gain can be used to
overcome the read noise of the fast amplifier, this mode is most useful in
applications requiring low-light sensitivity at high frame rates (e.g., Single
molecule fluorescence, ion imaging, etc.). Only 25x - 100x EM gain is required
to overcome the read noise of the camera. Using excessive EM gain will not
improve the overall signal to noise ratio (SNR).
Note:
An image read out of the Multiplication Gain {Electron Multiplied} port
is the mirror image of the same image read out of the Low Noise port. Unless the
application software automatically corrects the orientation when the selected port
changes, you may need to specify a horizontal-flip of the image.
2. Low Noise: When the camera is using this amplifier, electrons (signal) generated
in pixels are clocked through the standard serial register. The amplifier is
designed to take advantage of the dynamic range of the CCD and is most useful
when the frame rate is not critical. (e.g., bright field, fixed cell fluorescence, etc.)
Note: An image read out of the Low Noise port is the mirror image of the same
image read out of the Multiplication Gain {Electron Multiplied} port. Unless the
application software automatically corrects the orientation when the selected port
changes, you may need to specify a horizontal-flip of the image.