Optical fiber and an underwater shockwave generating device employing the same

An underwater shockwave generating device, comprising;

• an optical fiber,
• a reflector having a concave surface at a front end,
• a blocking membrane closing an opening of the concave surface,
• a liquid charged between the concave surface and the blocking membrane,
• wherein the reflector has the concave surface of an ellipsoid of revolution shape in which a major axis is a rotating axis, and a centered hole for the optical fiber to communicate with the concave surface formed on the major axis,
• wherein the optical fiber comprises a linear main body part and a laser beam convergence part disposed on a front end thereof,
• wherein the optical fiber is fixed to the reflector so as a front end of the laser beam convergence part is located on a focal point of the concave surface,
• wherein an interior angle with respect to a radial direction of a lateral face of an axial cross-section of the laser beam convergence part continuously or non-continuously and gradually decreases toward the front, and
• wherein an outer surface of the laser beam convergence part is configured to be a mirror surface by mirror finishing.