|Smoke and Mirrors: Ultra-Rapid-Scan FT-IR
The instrument was purged with dry, CO2 -free air while the
data in this slide and the next were recorded. This interferogram was recorded from a
model rocket igniter mounted at the source location, 660 ms after ignition. The burning
was quite erratic as can be seen from the interferogram baseline. The time interval shown
is 6 milliseconds, so the fluctuations have components up to at least 1 kHz. At a
conventional scan velocity, these fluctuations would have a disastrous impact on the SNR.
The same measurement approach was tried with gunpowder but the experiment fizzled. The 6
millisecond interval corresponds to 166 scans per second, or 5000 rpm operation.