I have a CW laser which is modulated by an optical chopper rotating at 1kHz. The modulated CW beam struck a sample holder and the absorption signal is recorder via an Infrared Associates MCT detector. The MCT detector, in turn, is connected to its own preamplifier, which in turn is connected via a BNC to a lock-in amplifier (SRS830 model). The optical chopper control provides a reference signal that is fed to the lock-in amplifier.
My data is collected via an NI USB 6210 DAQ (data acquisition) system.
The SRS 830 is able to provide instantly the magnitude and phase of the signal. However, I am absolutely lost on how to use this data to reproduce a vibrational spectra. The data I collect in the time domain corresponds to the absorption signal of the sample in the frequency domain.
I have been trying desperately to find literature on the subject of spectrometer building, but it seems I almost need a degree in physics to do this (I am a chemist, btw).
A depiction of the system I am trying to recreate can be shown here:
https://pubs.acs.org/cms/10.1021/ja200539d/asset/images/medium/ja-2011-00539d_0002.gif
A full description of the system can be found here:
https://pubs.acs.org/doi/10.1021/ja200539d
Can anyone provide me with some useful information and tips on spectrometer building, on how to understand signal processing from a IR detector and what should I do to get a spectra from the collected data I have?