A method and system for the controlled irradiation of optical fibers in a process for fabricating optical fiber components such as Bragg grating devices. The crystal grains are of a main component represented by the formula ABO3 and an additive containing a rare earth element wherein A is at least one of barium, calcium, and strontium, barium being an essential element, and B is at least one of titanium, zirconium, and hafnium, titanium being an essential element. The panel type speaker has high excitation efficiency and a simple structure, making it easy to add an acoustic characteristic regulating mechanism. The memory router stores memory partition information, which describes the memory allocated to the processor. In order to keep the area between the parts which can move in relation to each other as small as possible, the threaded hollow spindle is mounted in a rotationally fixed and longitudinally displaceable manner on a catch device which can be rotationally driven around the axis of the hollow spindle. A consistent data copying is guaranteed by circulating the determined guarantee time via the loop communication route.