MS Macrosystem
3D Laser Beam Tutorial: Part 1.
 
Fig.1 Load the program. The example image will appear. See "samp2.bmp" at left down corner of the Status Bar to confirm the image file under processing. The Main Window looks like fig.1. The Status Bar shows original image size in pixels, second panel, and,  next to it, the 3D window size (clickable). The 3D window is animated (rotations) by default. Stop the animation by pressing square button at the Animation Control Tool  as shown in fig.1, red arrow. To run rotation again clock wise or anticlock wise, click "Run" triangle at the Animation Control Tool. The Main Window can be at 2 basic modes 3D maximized and 2D maximized. To toggle between those modes use 3D>2D button at left down corner.

Fig.2
Press 3D>2D button as shown by lower red arrow in fig.2. This will maximize 2D sub-window. Click param on/off button as shown by upper red arrow to initiate beam parameters calculations. The parameter buttons will get enabled, see fig.2, left side, gray button group. Press Centroid in this group. This will calculate centroid position and show it as "xC=... and  yX=... values in pixel at left side. 
Fig.3 Press StatTable in parameter button group. The ellipse will be calculated and drawn around the beam. The ellipse is found as least square fit for the beam at 13% intensity level, see white ellipse line marked by the blue arrow. The Gaussian fits are calculated for both vertical and horizontal cuts, see red line marked by the cyan arrows. The fit result, red line, is drawn together with measured profile, white line. Gaussian fit is calculated as least square to all points in profile. 

Note that the beam samp2.bmp image is not spread to the whole palette, you can correct this by autoscaling, (see below). 


Fig.4
See diameter measurements in both pixel units and microns. The most reliable diameter measurement for Gaussian shaped (single mode) beams is Gaussian width. For complicated beam use slit diameter measurement as defined by ISO, see "slit dia y,x" in macrons or ISO slit x1,x2,W.

Fig.5 
Click 3D>2D button to maximize 3D sub-window. Go Menu>Data>AutoscaleZ to scale Z into whole palette scale. See change of the image, top became white instead of green. Go menu>View>  check following options: 3D slicers, X-axis arrow, and Scrolls. By "Slicers" we call the semitransparent cut planes used to obtain orthogonal cut profiles, see Magenta arrow. From Options menu check "Contour" option to see contour lines.
Adjust light position relative to using Light position tool, that is indicated by the cyan marker in fig.5. Use Mouse-down and drag operation anywhere within the tool to change light position relative to surface origin. 

Fig.6
Use Menu>Options>Reflections  to make surface specular reflective. This helps to see fine structure of the surface. Use Zoom Up to enlarge surface. Zoom is activated either from menu or by magnifier buttons ("+" and "-") in tool bar. Adjust light position to see offset noise at low intensity level., see gray on the fig.6. Click into the Slicer to pass focus to it and Drug it to different position.
Go Menu>View>2D cut View   to initiate 2D cut form.


Fig.7
Use the form to see profiles of the beam at the slicer position. To change position of the cut on surface either move the slicer, or use slider in 2D cut View. 
You can use "lock to 3D slicers" option as shown on fig.7 to link move of the slider on 2D form to 3D slicer position.

3D Graphics for laser beam analysis

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