Sigma LBA-714PC, LBA-710, LBA-300, LBA-712, LBA-708, LBA-500PC, LBA-700 Display Thresholds, Color Bar

•If the Set Reference Source is set to Auto Gauss, and the Gauss Fit item in the Computations dialog box is checked, then the beam profile resulting from a computed Gaussian fit to newly acquired frames will be automatically copied to the Reference frame. In this mode, setting a reference frame manually does not make any sense because the next frame brought into view will automatically update the contents of the reference frame.

Note: In the last two examples, if the Gauss Fit item is not checked and set to Whole Beam, then no fit data will be available and therefore nothing will be copied to the Reference frame.

3.2.7.9Display Thresholds

You can add Display Thresholds to the beam display that permit you to see when energy intensities fall into regions that may be of significance to your application. You can set a Lower and an Upper threshold. Setting the Lower threshold to zero will disable its operation. Setting the Upper threshold to its maximum value will likewise disable its operation. If the Energy of Beam setting is set to zero then the maximum value is 255 for the LBA-300PC; 1023 for the LBA-400PC; 4095 for the LBA-500PC. If you have calibrated the beam energy, then the maximum value will be scaled accordingly.

The visual effect of setting active threshold values is to force the displayed beam intensities that fall between the two threshold settings, to follow the Beam Color selection. Beam intensities that lie below the Lower threshold, or above the Upper threshold, will revert to a different color style. Intensities that lie within the threshold region are defined as being in-bounds. Intensities that lie outside the threshold region are said to be out-of-bounds.

If your Beam Colors is set to one of the colored selections, i.e., Color Bands, Color Continuous, Green, or Yellow; then the out-of-bounds colors will be replaced with the Gray Scale palette.

If your Beam Color is set to the Gray Scale selection, then the out-of-bounds colors will be replaced with the Color Continuous palette.

Hint: Program both the Lower and Upper threshold values to visually indicate that your Top Hat beam’s intensity remains within a certain range. Program just the Upper threshold value to see if your beam’s peak intensity exceeds a certain maximum value.

Note: Using the Lower threshold feature in 2D, combined with a colored beam selection will have the effect of making your beam profile displays disappear. Use a Gray Scale selection if you want to preserve the beam profile displays.

3.2.7.10 Color Bar

If you check the Color Bar item, a color-coded Z axis intensity scale will appear along the right- hand edge of the beam display window. This scale will reflect the colors that are currently operating on the beam display. The numerical amounts indicate the intensity value that is required to produce the associated color. Use this only as a guide, unless you have perfect color/gray-scale acuity.

Operator’s Manual	81	LBA-PC
Doc. No. 10654-001, Rev 4.10