Software Manual Section 09

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Holder Control
	Introduction This tool controls the movement of the sample stage (holder). You can store any number of locations and move to them later with just one click. Among the better features is the option to load an SEM image of your sample into the "background" of your holder display. Once everything is nicely aligned, it is possible to just click into the image to have the stage move to the respective location.
	Beam/Stage Position The current position of the primary ion beam on the sample is displayed here. (Yes, I know, the beam is always at the same position and it is the sample stage that is moving. But -in the spirit of universal relativity- I will simply ignore this fact and pretend that the beam is moving across the sample.) The values shown represent the X- and Y-positions in microns. The possible range for both values is from -10000 to +10000. This display will be automatically updated whenever the stage is moved with the 'joystick'. There are several different ways to move the beam (stage) from the computer. The simplest way is to enter a numerical value for X or Y here. The stage will immediately move to the new position. It is also possible to move the "Beam" (stage) in steps by clicking on one of the four arrow buttons in this control. Note that a red box "Stage is Moving" will pop up every time the step motors are moving the stage. Wait until the move is complete before entering the next command. The duration of the move depends only on the length of travel.
	Step Size With this pull-down menu the step size for the arrow buttons (discussed above) can be changed.
	Sampe Unload This is a button that moves the holder to the 'Unload' position for sample exchange. It is the same as moving the "Beam" to position X = -10000 (microns) and Y = 0 (microns).
	Beam to Center This button moves the "Beam" to the center of the moving range (i.e. the beam is moving to position X = 0 and Y = 0).
	Graphical Stage Display In addition to the digital display of the "Beam" position, its location on the sample is also shown graphically in the large diagram. The displayed range from -10 to +10 for X and Y (this time in mm) is the full possible range of "Beam" positions. Note that the 'background' picture of the stage display may vary. See comments below.
	Target Position The "Target" is just another point somewhere on the sample stage that can be moved around with this control in much the same way as the beam with the "Beam/Stage" contol described above. All by itself, the "Target" doesn't do much and moving it to different positions on the sample has no physical effect on the 3f instrument. Think of the "Target" as a position that you may want to move the beam to in the future (hence its name). How this can be done is discussed below.
	Beam to Target Clicking this button is the easiest way to move the beam to the position of the "Target".
	Target to Beam This button does just the opposite of the previous one, it moves the "Target" point to the current location of the beam. Why would you want to do this? One possible use of this function is to briefly 'store' an important position. After you have moved the "Target" to the "Beam" position, you can move the "Beam" around on the sample, while the "Target" stays where it is. One click on the "Beam to Target" Button then gets you back to the previous location.
	Move Target with Mouse There is one more way to change the position of the "Target": The position of the "Target" is always shown in the graphical stage display. It is possible to move it directly in the display with the mouse. Simply click on the blue dot and drag it to a different location. The changes will immediately be reflected in the digital "Targe Position" indicator. The same does not work for the "Beam" position, but after moving the "Target" to the desired position, it only takes one click on "Beam to Target" to move the "Beam" there, too.
	Save Locations In addition to the "Target" positions, it is possible to save an unlimited number of other "Locations". Simply enter a name here (e.g. 'Point A') and click "Store". This will store the current position of the "Target" as a new "Location" with the name 'Point A'. With these "Locations" it is e.g. possible to first record the coordinates of all particles and standards that are to be measured and then move from one to the next once the instrument is tuned up for high mass resolution.
	Locations in the Graphical Stage Display All stored "Locations" are indicated with open blue circles in the graphical stage display.
	Select/Edit Stored Locations This pull-down menu will display a list of all "Locations" that have been stored. (In this case, the stored "Locations" are 'Point A' and 'Point B'.) By selecting the name of a stored "Location", the "Target" will immediately be moved to the corresponding position. Select "-Delete All Stored Locations-" to erase the list of "Locations" that has been stored. Selecting "-Delete Checked Location-" will erase only the "Location" with the 'check mark' in front of it (i.e. the "Location" that was last selected). Example: To erase 'Point A', you first have to select it. This puts the 'check mark' in front of it. Then select "-Delete Checked Location-".
	Background Image To make the navigation on the sample holder somewhat easier, it is possible to load several different images into the 'background' of the graphical stage display. The following background pictures are always available: SEM Stub: This is just a circle, showing the approximate dimensions of the standard SEM stub sample holders for general orientation. Thin Section: This is also a circle, only bigger, showing the rim of a standard one-inch Ø thin section. 3 Holes: This is a background image with the standard CAMECA sample holder with 3 rectangular holes. In addition, it is possible to Load a New Picture into the background. This function is described below.
Load New Picture When "Load New Picture" is selected from the "Background Image" pull-down menu, this window opens. From here a picture for the background of the graphical stage display can be selected. This of course requires, that you have a digitized SEM or optical microscope picture of your sample available. Currently it supports four basic image formats: Raw Binary, Table in ASCII Text, uncompressed TIFF and BMP. (I may add more formats later.) Click on the appropriate button and select the file containing the image. If everything works fine, the "Preview" window on the left should show the selected image. The name and the pixel size of the image is also displayed. Click "OK" or "Cancel" to exit this window.
	Alignment of the Background Image After a new image has been loaded, it is immediately displayed in the background of the graphical stage display. Most likely, it will not yet be aligned correctly. With these four controls, the background image can be moved, scaled and rotated until it corresponds to the actual sample in the instrument. The Horizontal and Vertical Offset controls move the image in increments of one pixel (I think). The % Scaling control changes the size of the image. The normal size is 100 %, where one pixel of the picture corresponds to one pixel on the screen. The Degree Rotation control rotates the images around its center. A positive value results in a CCW (counter clockwise) rotation. As in all controls of this kind, one can either enter a numerical value directly or click on the little up/down arrows to change the values. It will probably take some practice to move the images into the right position, but I think this could be a very useful tool in many situations. With a little bit of practice, we could also figure out at what magnification an SEM image has to be acquire, so that no scaling is necessary.
	High/Low Contrast By default all grayscale pictures are loaded at high contrast, which means that the brightness range goes from all black to all white. While this is a good setting for viewing the picture, it can make it difficult to see the labels for "Beam" and "Target". Therefore, it is possible to switch to low contrast for the background picture in the graphical stage display. The effect of the different settings are shown below: High Contrast Low Contrast
	Reset This button sets all the alignment controls for the background picture back to their default values.
	Exit Closes this window. Note that it is not necessary to close this window during a measurement. There is no reason why this window couldn't stay open all the time in the background.

FJ Stadermann	Back to Top	Next Section