Pulsed holmium lasers application for solid bodies destruction

Abstract

Two pulsed holmium laser and two experimental devises on their basis for crushing stones and burning bones ware done. The lasers made using fiber-optic components schemes: solid-state laser pump diode – fiber-optic ytterbium laser pump – low-power fiber optic pulsed three-level holmium laser fiber optic holmium power amplifier; solid-state laser pump diode – fiber-optic ytterbium laser pumping – fiber-optical shutter based on coil holmium-doped optical fiber and reflecting fiber Bragg gratings – fiber-optic three-level pulsed holmium laser. Fiber-optic lasers advantage is in the presence of thin, flexible fiber-optic cable, allowing carrying out energy impact on destructible objects located in remote places. The crushing stone experiments were done on objects with properties similar to those of kidney stones. The same experiments were carried out on burning of bone tissue. The results of the experiments confirmed the possibility solids states destruction by exposure of holmium laser pulsed radiation with wavelength of λ = 2050 nm. It was established that the destruction is possible due to two mechanisms of action: shock cavitations crushing the stone in liquid media and thermal burn of bone tissue by method of “light scalpel”. It was revealed that cavitations' crushing is most effective for less dense formations and the thermal burning for denser. The experimental devises can be used for medical purposes as well as for breaking and cutting of other materials.