1：Experimental Design and Method Selection:

A Spectra Physics Nd:YAG laser with a simultaneous wavelength output of 1064 and 532 nm was used in the LIDT test system and pump-probe image system. The laser was under TEM00 mode. A 1064 nm laser with 10 ns pulse width and a 532 nm laser with

2：5 ns pulse width were set as the pump and probe lasers, respectively. The beam diameter was approximately 70 μm at the focus. A long working distance microscope and several Spiricon SP620U charge-coupled devices were used to achieve μm scale imaging resolution. Sample Selection and Data Sources:

The fused silica samples (50 × 50 × 10 mm) were ground and polished by SiC abrasives and CeO2 powder of different sizes and removal depths.

3：List of Experimental Equipment and Materials:

Spectra Physics Nd:YAG laser, Spiricon SP620U charge-coupled devices, long working distance microscope, fused silica samples, SiC abrasives, CeO2 powder.

4：Experimental Procedures and Operational Workflow:

The pump laser first irradiated the tested sample from the left side of the input surface, passed through the bulk material and exit surface, and finally exited to the air side. Meanwhile, the probe laser angle irradiated the test area at a specific delay time to diagnose the damage information of the tested sample.

5：Data Analysis Methods:

The difference between the particle locations in the two images was compared and divided by the interval time of the two probe lasers (usually 30 ns) to calculate the particle ejection velocity.