Beam Sampling Grating (BSG) is an expensive optics due to its complicated manufacturing process. However, BSG is vulnerable, or easily laser-induce-damaged, when suffering intense ultraviolet laser in laser system. Enhancing the laser-damage resistance of BSG and extending the lifetime of BSG is necessary and economically efficient. In this work, base on that laser-damage precursors on the surface of optics can be mitigated by wet chemical etching (using Hydrogen Fluoride based solution as etchant), it is proposed that shallowly wet chemical etching can be used to enhance the laser-damage resistance of BSG, thus to extend the lifetime of BSG. Meanwhile, it is also found that the sampling efficiency of BSG changes little during shallowly wet chemical etching and can be acceptable for some application in laser system.

Beam Sampling Grating,Wet Chemical Etching,Laser-damage Threshold