Spectrometer Oriel Mir 8000 Instrumentation

[Paeline]

Hi people,

In our lab, we are currently using a FTIR spectrometer manufactured in 1998 : Oriel MIR 8000. Kind of old stuff.
Anyway, we would want to get back the raw data from the spectrometer, and calculate the Fourier Transform ourselves (with Labview obviously).
We assume that the FFT is processed by the software provided by Oriel after the raw signal is acquired by a special acquisition card Oriel also provided.
But we don't have any idea about where to got the raw signal from the spectrometer and how does it looks like...
I have been searching around quite a lot but it seems that not a lot of people tried to develop something with this instrument.
It would be great if someone knows something about that all.

Thanks !
Pælín

[AnalogKid2DigitalMan]

Paeline:

I have some limited experience with the 8000- our unit here blew out the MSB on the A/D converter board and pretty much rendered the unit useless. I managed to get another A/D chip for the board (very limited availability) but could not solve the issue- there was damage to other chips on the board. What I can tell you, since Oriel (now owned by Newport) supplied me with the schematics, is that there is more than A/D conversion going on in the board. There looks to be a custom ASIC to do signal processing in hardware, circuitry to perform filtering, various amplifiers for setting gainds, and digital control lines to monitor and control the spectrometer. It looks like they took the approach they did in hardware to simplify post-processing of data in software.

We no longer have the unit. I think you will still need their board and software in order to control the spectrometer. Due to custom chips I can't tell what processing is being done to the analog signal, but it arrives to the A/D chip ADC4355 (U21) at pins 14 (gnd) and 15.

When I get a chance, I'll try to trace back where the raw signal comes into the board at. (EDIT- looks possibly like JP1, pin 4 (+) and pin 6(-), not quite sure yet)

Hope this helps

-AK2DM

Message Edited by AnalogKid2DigitalMan on 07-31-2008 09:24 AM

[AnalogKid2DigitalMan]

Paeline:

My foggy memories of over 3 years are coming back. The card I spoke of was within the MIR housing on a backplane with some other cards. What I thought was an ASIC is actually an EEPROM. Regardless, I still think you need to run the instrument with the Oriel software and the card that resides in the PC. You should be able to locate leads coming from the detector module to get access to the raw detector signal. I think these went to a pre-amp module that piggy-backed to the A/D card on the instrument's backplane. I do not have the entire set of schematics, just the A/D card. If it helps, I have attached that file. Seeing that the instrument was at it's end of service life (a USB based setup replaced it) and the EEPROM is essentially a 'black box'- without the code no secrets are being given away here.

[AnalogKid2DigitalMan]

Paeline:

I found something that may be a fistful of diamonds or a lump of coal for you. Here is the LabVIEW library of vi's from Oriel to control and acquire data from the 8000.

Never have used them, they are quite old (circa 1998).

-AK2DM

[Paeline]

AnalogKid2DigitalMen :

Thanks a lot for the help.
I had a look at the Labview Library, and actually I was able to see a lot of interesting VI for our projects when opening the library with Labview 8. Are these VI from Oriel or from an independent developer ?
Anyway, we have more troubles now. I tried to upload the library on our old computer which drives the spectrometer with the Oriel software.
When opening the library with Labview 6, it is opening a whole VI (Oriel Instruments MIR 8000) in which I guess contains all the VI from the library. I am right ? Isn't it possible to open each VI separately with Labview 6 ?

Another thing is that we first succeeded in getting some interferometer with the VI, but when trying to get the same spectrum with the Oriel software, the spectrometer goes crazy.
Now we are unable at all to make any ZPD adjustment or whatever, neither using the VI neither the original software.
Did you also had troubles when using the VI, if you did ? We are wondering if it is basically a hardware trouble or a software one (like if running both the VI and the software messed it all up).

[AnalogKid2DigitalMan]

Paeline:

Like I said, I never have used them. I think they came from Oriel, they may have subcontracted the developement of them, somewhat poorly written with a lot of variables and sequence structures upon further inspection. You should be able to open up individual vi's within the library. Looks like Oriel Instruments MIR 8000 is the top level main vi.

Regarding improper operation of both the vi's and the Oriel software, have you tried shutting off all hardware and the PC and powering everything back up? That's about all I can suggest. I apoligize for any inconvenience, I would not foresee this happening but have never used the vi library before and not sure if any documentation is included anywhere.

-AK2DM