Comparison of Ultrafast Coherent Anti-Stokes Raman Scattering Techniques for One-Dimensional Imaging

One-dimensional ultrafast coherent anti-Stokes Raman scattering measurements are investigated for two chirped-probe pulse durations, 1.2 ps and 6.2 ps. A femtosecond coherent anti-Stokes Raman scattering (fs-CARS) instrument is demonstrated with a spatial dimension of 2 mm oriented vertically in the lab reference frame. One kilohertz single-shot measurements are demonstrated at elevated temperatures up to 1200 K in an atmospheric pressure flame. Two chirping rods, 5 cm SF-6 and 30 cm SF-10, were used to sample different segments of the Raman resonance. Single-shot data are fit against a time-domain model for resulting temperature measurements for both chirping rod conditions. Higher precision is revealed with the longer probe pulse for certain regions of the image, which correspond to higher signal-to-noise ratios. Variations in probe pulse energy are examined, highlighting the importance of properly quantifying shot-to-shot stability.