Zeiss LSM 880, Operating Manual

Page: 281 / 690

CHAPTER 1 - SYSTEM OPERATION
LSM 880 Left Tool Area and Hardware Control Tools ZEISS
10/2014 V_01 000000-2071-464 275
(2) Correlation G(
t
)
The diagram shows the correlation functions for each activated channel. The zoom function can be used
to display certain diagram areas of interest in an enlarged form. Use the left mouse button to click on the
margin of the area of interest in the diagram, keep the mouse button pressed and draw a rectangular
above the area of interest in any required direction. On release of the mouse button, the selected area is
displayed in an enlarged form in the diagram. The scaling of axes is matched automatically.
By clicking the right mouse button you can choose
between different options in the
Correlation
context menu (Fig. 367).
•
Select the line Reset Diagram Zoom with the
left mouse button to reset the zoom value.
The data (measuring values) of the diagram can be
copied to the clipboard or stored directly as an
ASCII file via the context menu.
•
Select the line
Copy data to clipboard
with a
click of the mouse if you want to insert the data
directly into other WINDOWS programs via the
clipboard. The Paste function permits direct
insertion of these data into the required
program.
•
Select the line Write text to file to store the data in an external ASCII file (.txt). Normalized values
will also be exported in this way.
Note that the
Export
button in the
Display Correlation
window will only export the original
values.
The diagram display can be manipulated with the context menu as follows:
•
Selection of
Abscissa logarithmic
will scale the x-axis logarithmically
•
Selection of Ordinate logarithmic will scale the y-axis logarithmically.
•
The line width allows you to select the thickness of the graph. Six settings are possible.
•
Selection of
Normalize
will normalize the curves to 2 (Fig. 368):
If
Normalize
is selected the G(0) value corresponding to the number of diffusing particles will be
normalized to 2, not the total correlation to which also other processes like triplet state can
contribute. All other values (subtracted by 1) will than be multiplied by the correction factor defined
by the ratio of 1 to [G(
0
)-1] and increased by 1, hence G (
t
)
normalized
=[1/ (G(
0
)-1) * (G(
t
)-1)]+1.
Deactivating Normalize will display the normal correlation curve.
Normalization only works for a curve, for which a fit has been conducted in
FCS Fit
and hence a
G(0) is available.
Fig. 367 Correlation context menu