Sigma LBA-400 Manuel D’Utilisation

Figure 23

If you enter an Energy of Beam value of 0 (zero) the

energy

related results items, such as,

Total (

energy

), Peak (fluence), Min, Gauss Height, etc., will be computed in processed

digitizer units. Processed digitizer units are called counts, and are dimensionless. In this case,
no units will be displayed in the results window.
Any non-zero entry will cause the displayed results to be reported in the units selected. Fluence

results will also rely upon the Pixel Units entry to complete the energy density definition. A

Pixel Unit selection of PX stands for pixel spatial units. The PX unit is dimensionless.
When the Scale Units are set to µm, mm, or cm, the

energy

density results are computed as

energy

/cm². When the scale units are set to PX or m, the density results are displayed as

energy

/PX², or

energy

/m² respectively.

3.2.6.2 Energy Calibration Procedure

After you have set up the LBA-PC and are ready to acquire data, the

energy

calibration procedure

involves the following three operation:

1. Execute

Ultracal! operation.

2. Acquire a calibration frame on the 2D display and a matching

energy

measurement on an

external power/energy meter.

3. Enter

the

energy

and select the units in the Computations dialog box.

3.2.6.3 Quantitative display, on/off

Check the Quantitative box if you want to have the quantitative results item appear in the results

window. Checking this box only controls the display of these results. Even if not checked, these

results will be computed. The only way to turn off all computational activity is to minimize the

Results display window. The displayed quantitative results consist of the following:

• Total

energy

•  % in Aperture
•  Peak fluence
•  Min
•  Peak Loc..ation, in X and Y
•  Centroid location, in X and Y
•  Beam Width, in both X and Y or Major and Minor axes
•  Beam Diameter

Operator’s Manual

LBA-PC