A multi-mode to single mode optical interface device includes an optically pumped edge emitting semiconductor laser device and a lens. The optically pumped edge emitting semiconductor laser device includes (1) a gain area, and (2) an edge located single mode output. The lens focuses a multi-mode optical fiber output beam into a substantially line shaped output beam focused onto the gain area of the optically pumped edge emitting semiconductor laser device. A method for converting a multi-mode optical signal into a single mode optical signal includes (1) focusing the multi-mode optical signal onto a gain area of an optically pumped edge emitting semiconductor laser using at least a line focusing lens, and (2) converting the multi-mode optical signal into the single mode optical signal using the semiconductor laser.