抄録
Laser microdrilling in a metal foil (stainless steel, thickness 20, 40, 100μm) was carried out with a nanosecond pulsed Bessel laser beam (wavelength: 532nm). Microdrilling without precise control of the work distance was shown to be possible due to the deep focal depth of the Bessel beam. The diameter of a penetration hole thus formed was maintained at several μm while the work distance was changed within a range of several mm. The effects of foil thickness on the relationship between the irradiation energy densities and averaged ablation rates were examined. It was revealed that these values depend significantly on the thickness of the foil. It was also found that the diameter of the hole can be controlled by adjusting the irradiation beam energy.
