Apparatus for coupling a multiple emitter laser diode to a multimode optical fiber

摘要

A small diameter multimode optical fiber with a low numerical aperture (i.e., 0.1) is used as a microlens to collimate the output emissions of a laser diode before butt coupling the output of the laser diode to an optical fiber. The optical fiber used as the microlens is chosen such that its diameter roughly equals the diameter of the fiber to be coupled to the laser diode. One end of the fiber is mounted in a fixed position and the other end of the fiber is slip fit into the end of a hollow receiving member mounted in a fixed position and running parallel to the axis of the fiber. The collimation is performed in the high NA direction of the output of the laser diode. The output of a bundle of butt coupled optical fibers may be used to pump a laser system.