Talk:Fourier-transform infrared spectroscopy

don't get it

It states what the difference is between it and standard spectroscopy (lots of colours at once and in various different patterns), but not why you'd want to do that.

conceptual introduction

Reflectance (ATR) is also important. There are pictures of ATR devices in Wiki commons, but in FTIR a cylindrical rather than a flat crystal is used. I didn't think it worth going into so much technical detail. Petergans (talk) 21:05, 1 August 2010 (UTC)

Secondly, I don't think that the illustrated interferogram is real. It looks like a sinc function which would imply a monochromatic source. Petergans (talk) 21:27, 1 August 2010 (UTC)

Good point, it is too specific to say the light passes through the sample. I'm sure it can be reworded somehow. :-)

You're right that the interferogram has more peaks than a typical spectrum. I don't know where it's from. I have a few interferograms on my computer, I guess I could plot and upload one when I get a chance? :-) --Steve (talk) 21:58, 1 August 2010 (UTC)

I've just looked at Frustrated total internal reflection. I believe that this is the same as ATR. Some general clean-up is needed. I don't think that the link as it stands is helpful.Petergans (talk) 08:48, 2 August 2010 (UTC)

Another point. "while a disadvantage is that FTIR cannot use as sensitive a detector as dispersive measurements can". I wonder if this is any longer true. See Mercury cadmium telluride#infrared detection.Petergans (talk) 15:09, 2 August 2010 (UTC) Also mct vs DTGS comparison

Detector elements could be same, but FTIR detection is crippled by restriction on electronics. As a result, sensitivity of dispersive measurements is greatly superior to FTIR. It is not only lock-in detection, which gives orders of magnitude better S/N, even low-pass electronic filter helps a lot for NIR detectors - those filters are restricted in FTIR by the scanning speed. Materialscientist (talk) 23:32, 2 August 2010 (UTC)

For the sensitivity claim, I just copied it out of a book without double-checking. I don't want to say whether I think it's right or wrong without looking into it more.

For "frustrated total internal reflection", I just moved a redirect from one page to another . The acronym is legitimate, i.e. people really do occasionally use the initials "FTIR" to stand for "Frustrated Total Internal Reflection" rather than "Fourier Transform Infrared spectroscopy". If you have a problem with the frustrated total internal reflection article, you should discuss it at that page, which I haven't looked at. (The way I learned it, it's closely related to ATR but not quite the same, or at least the terms are used in slightly different situations.) Anyway, this is a disambiguation-type link, I think it needs to be there even if the frustrated total internal reflection article is bad. :-) --Steve (talk) 01:09, 3 August 2010 (UTC)

Detectors

There should be a section on detectors. Can anyone help? I created a stub on triglycine sulfate which, amazingly, was (as of 5 Aug 2010) not even mentioned in infrared detector. An important point is that PbS and related detectors are useful in NIR and are often available in UV/Vis spectrometers with a wavelength range that extends into the NIR.Petergans (talk) 16:30, 5 August 2010 (UTC)