JEOL and Cameca spectrometer orientations

[John Donovan]

I'm creating an output format in Probe for EPMA for the consensus k-ratio project and wanted to specify the spectrometer orientations for each spectrometer number (for checking simultaneous k-ratios).

Of course JEOL and Cameca utilize different conventions(!), and JEOL apparently used different conventions for the 8900 vs. later instruments. Here is what I have:

Cameca               5

               3                            2

                       SX100/SXFive

                4                           1


JEOL                      5

                3                            4

                       8900/8800

                 1                           2


JEOL                      3

                2                            4

                       8200/8500

                 1                           5


First, are these above schematics correct?  I'm assuming the 8230/8530, JEOL iSP100 and iHP200F are the same as the 8200/8500...

Second, does anyone know the actual angles around the instrument for each spectrometer orientation?  That is: 270, 45, etc. assuming that north (the back of the instrument is zero degrees)?

[Karsten Goemann]

Our 8530F plus is like your 8500 schematic.

The angles are not simple, see attached drawing. Could probably measure them in the drawing but may be easier to just ask JEOL, unless someone else has the angles already?

[Probeman]

Our 8530F plus is like your 8x00 schematic.

The angles are not simple, see attached drawing. Could probably measure them in the drawing but may be easier to just ask JEOL, unless someone else has the angles already?

Julien Allaz confirms that there may be regional differences in the JEOL spectrometer arrangements.





Otherwise it would be just too easy!

[Probeman]

The point of this topic is to document the JEOL (and Cameca) spectrometer orientations as described in The FIGMAS Round Robin Excel spreadsheet by Aurelien Moy.

It really shouldn't matter what the spectrometer ordering is for most purposes. Even for the FIGMAS simultaneous k-ratio measurements it's just a convention. The only reason I can think of why we should document the spectrometer orientations, is for performing a Bragg defocus secondary fluorescence correction along the lines published by Ben Buse, where the spectrometer to boundary orientation must be defined (and the Bragg defocus effect measured using beam scans).

https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/abs/secondary-fluorescence-in-wds-the-role-of-spectrometer-positioning/94F6F5D3992B37BFBB8B4116BB4605D3



If I ever get the time I'd like to implement this procedure in Probe for EPMA, so maybe adding a way for users to define this in PFE is worthwhile.

This is a very rough calibration, but this is this is what I came up with:



The angular distances I calculate are:

350 - 303 = 47
303 - 255 = 48
100 - 39 = 61
39 + 10 = 49

So 4 spectrometers are about 47 to 49 degrees apart (+ or -), but one is 61 degrees away to allow for the SE detector I guess. If anyone has numbers from JEOL schematics please let me know what the actual angles are.

[John Donovan]

In the above post we attempted to determine the spectrometer orientation angles for JEOL EPMA instruments. I'm hoping that someone out there has a JEOL schematic which would provide the actual angles for the WDS spectrometers.

Based on rotation angles with 0 degrees at the top (North or back) of the instrument and starting with the lower left spectrometer (which we refer to as a Type 1 JEOL spectrometer orientation)  and proceeding clockwise we obtain these rough numbers:

JEOLSpectrometerOrientationType=1
SpectrometerOrientations1="250"
SpectrometerOrientations2="300"
SpectrometerOrientations3="350"
SpectrometerOrientations4="40"
SpectrometerOrientations5="100"

JEOLSpectrometerOrientationType=1
SpectrometerOrientations1="250"
SpectrometerOrientations2="100"
SpectrometerOrientations3="300"
SpectrometerOrientations4="40"
SpectrometerOrientations5="350"

Does anyone have better numbers for these orientations?





Much thanks to Julien Allaz for these very pretty schematics!

[John Donovan]

So we finally got some information (from a little bird) on the exact orientations for the JEOL spectrometers. The numbers we guessed by looking at a picture from above were only off by a degree or two, so it's not a big deal, especially since this information is only going to be used for a Bragg defocus corrected secondary boundary fluorescence (someday!).

If you have recently updated PFE and got the message asking which JEOL spectrometer orientation your instrument is (see above post for details), you might want to edit your Probewin.ini file as follows (101.5 degrees, really!?).

JEOLSpectrometerOrientationType=1
SpectrometerOrientations0="215"
SpectrometerOrientations1="253"
SpectrometerOrientations2="302"
SpectrometerOrientations3="351"
SpectrometerOrientations4="40"
SpectrometerOrientations5="101.5"
SpectrometerOrientations6="0"

JEOLSpectrometerOrientationType=2
SpectrometerOrientations0="215"
SpectrometerOrientations1="253"
SpectrometerOrientations2="101.5"
SpectrometerOrientations3="302"
SpectrometerOrientations4="40"
SpectrometerOrientations5="351"
SpectrometerOrientations6="0"   

The latest Probe for EPMA installer contains these updated values (for updating old installations), but it won't automatically update your Probewin.ini file for you if these entries already exist!