Design of Fiber Coupled High Power Laser Diode by Concave Mirror

Abstract-Based on high-power laser diodes series beam combine and fiber-coupled technology, a practical method of coupling between laser diodes and multimode fiber with concave mirror is presented. First, the output beam from a laser diode is collimated by a section of multi-mode fiber; beams are rearranged by the plane mirror and concave mirrors in space and coupled into the optical fiber by a non-spherical lens. The practical fiber coupling module have been designed, packaged and tested. In the module, six 980nm laser diodes have been coupled into a single core fiber, of 100μm core diameter and 0.22 numerical apertures. The fiber output power of 11.8W at current 3.0A has been obtained, with the total coupling efficiency of 75%. This fiber-coupled module with a compact structure, simplified optical construction, high-brightness output, can be widely used in medical, laser marking, material handling and other fields.