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Example: If the user has collected samples [1-1000] and the Sample limit it set to 100,

samples [900-1000] will be the only samples visible in the strip chart. Statistical results will

be computed using all the samples [1-1000].

3.2.9.2.2 Samples

The Samples indicator shows the total number of samples collected.

3.2.9.2.3 Check Boxes

The Check Boxes allow the user to specify what results items are to be graphed on the strip

chart. One or all of the following may be selected:

 Centroid X

 Centroid Y

 Peak X

 Peak Y

 Radius

3.2.9.2.4 Radius Relative to:

The Radius Relative to control modifies the display of radius information. The radius is

referenced from an Origin set up in the LBA-PC or from the continuously calculated

Average Centroid position.

3.2.9.2.5 Strip Chart Zooming

All strip chart data is plotted on the same horizontal and vertical scale. This situation will

cause traces that vary greatly along the vertical axes to dominate the vertical scale. Traces

that have small vertical fluctuations will show up as flat lines. In order to see small details

the user must stop or pause the data collection and drag a zooming box around the region of

interest. To do this, start in the top left, drag a box spanning downward and to the right

until the region of interest is selected. More than one zoom operation may be performed to

achieve the desired detail.

Zooming out can only be done once. The plot will return to full zoomed-out mode. Zooming

out is accomplished by dragging a box from the bottom right back to the top left. The size of

the zoom-out box does not matter because all zoom out operations return the plot to the full

view.

Note: The direction of the zoom operation (in or out) is controlled by the direction the box is drawn, down and to

the right to zoom in and up and to the left to zoom out.

3.2.9.3 Peak/Centroid Scatter Plot and Histogram

There are two ways to use the Scatter Plots in the Beam Stability window. One is to test stability

from the standpoint of spatial dimension using units such as millimeters or microns. The other is

Operator’s Manual LBA-PC

Doc. No. 10654-001, Rev 4.10