| 摘要 |
A Fourier transform spectrometer for conducting Fourier transform spectroscopy. The spectrometer has a light source emitting light to a sample via a rapid scan interferometer. The transmittance of the sample varies when stimulated. A stimulus generator gives a stimulus to the sample at regular intervals of tau asynchronously with a reference signal produced for the interferometer. A delay circuit produces a trigger delayed with respect to each stimulation to control a gate circuit. Radiation emanating from the sample is detected by a detector. The output signal from this detector is gated onto a band-pass filter after a given delay DELTA tau with respect to each stimulation by the gate circuit. The gate circuit produces a digital interferogram. The band-pass filter passes only those frequency components which satisfy the condition: m/2 tau <f<(m+1)/2 tau where m is a positive integer. The analog output signal from the filter is converted into digital form by an A/D converter and fed to a computer, which Fourier-transforms its input signal.
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