THORLABS BC207UV, Operating Manual

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BC207 Series Chapter 5: The Graphics User Interface (GUI)
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MTN026962-D02
present. Areas with a power level lower than the clip level will be ex-
cluded from further calculations.
Auto Rectangle ISO: The rectangular calculation area is calculated according to ISO11146-1
using multiple iteration steps. The clip level is determined during the
calculation.
Full ROI: The entire image area defined by the ROI is involved in beam calcula-
tions.
User Rectangle: A rectangular area, set by user input is defined as Calculation Area.
Enter pixel values which describe the Calculation Area position and
size or simply drag a rectangle into the 2D Projection window.
Auto Ellipse: An elliptical area is created automatically by the software around the
beam shape. Criteria:
Clip Level . Areas with a power level lower than
the clip level will be excluded from further calculations. The clip level
can be set up in the Application Settings.
User Ellipse: An elliptical area, set by user input, is defined as Calculation Area.
Enter pixel values which describe the Calculation Area position and
size or simply drag an ellipse into the 2D Projection window.
When "User Rectangle" or 'User Ellipse' is selected,
please enter size and position of the Calculation Area
numerically or drag and drop the borders of the user
rectangle (ellipse). All values are in µm or pixels, de-
pending on the
unit selection , and the point of origin
is situated in the upper left corner of the entire sensor
area. X (Y) Positions describe the position of the left
(upper) border of the user rectangle (ellipse). Further,
a defined calculation area can be rotated by entering
numerically the desired rotation angle.
The Calculation Area can also be set and visualized
within the
2D_Projection window. See the appropri-
ate chapter for details.
Clip Level of the Calculation Area
If the calculation area is detected automatically ( Auto Rectangle or Auto Ellipse ), the borders
of the Calculation Area in all four directions are defined by the calculation area clip level. The
border in one direction is set when all pixel values fall (seen from the peak) below the Clip
Level. Decreasing the Clip Level increases the Calculation Area which in return increases for
example the 4
s diameters, but also increases the noise. For a steep beam profile, 1.0% is an
optimal clip level value. If the beam profile is rather flat, it might be advantageous to lower the
clip level.
The clip level is set by default to 1 % and can be set between 0.01 and 13.5 %. In order to
quickly return to the recommended 1.0% clip level, just click to the box
Default (1.0%) .
Note The " Clip Level of Calculation Area" is different from the Clip Level used for beam
profile calculations!
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