Interferometric spectral imaging of liquid in laser ablation

The first experiment of time‐resolved spectral imaging of liquid in laser ablation is reported. An interferometric spectral imaging system dedicated to the measurements of the laser ablation is constructed. A pair of two‐dimensional arrays of images are formed by a lenslet array coupled with a polarization interferometer and superposed on a detection plane. Each image in the array is provided with a varied path difference by the wedge‐shaped liquid‐crystal polarization interferometer to generate the interference signals. These interference signals include all the information necessary to reconstruct a spectral image and can be collected simultaneously. The mechanism of ablation of phenanthrene/ethanol solution was investigated by making use of the time‐resolved spectral images of the laser induced plume. The results suggest that the photothermal processes are dominant in the ablation of the solution.