DRILLING METHOD AND DEVICE OF STRATUM IN LIQUID

摘要

A drilling method of a stratum capable of drilling a stratum such as an underground resource endowment layer in liquid by laser irradiation in liquid. A laser beam transmitted by a laser transmission means (20) is applied, as a laser beam having a wavelength exhibiting high absorptivity to liquid (90), from a laser induction bubble generating means (35) into the liquid (90) to generate a bubble flow (36) and a stratum existing in the liquid is drilled using a fracture action force induced by laser. On the other hand, a laser beam (41) exhibiting low absorptivity to the liquid (90) is applied from a laser irradiating means (39) and passed through the bubble flow (36) so that a thermal action force is applied to the stratum thus fracturing the rock and drilling the stratum. The fracture action force and thermal action force can be cooperated.