An optical transmission system includes a lens wafer to couple light into an optical transmission medium. The lens wafer includes a set of collimating lenses on a first side of the lens wafer, the collimating lenses to collimate beams of light from a plurality of light sources. The lens wafer also includes a focusing element on a second side of the wafer opposing the first side. The focusing element is to focus the collimated beams of light into an optical transmission medium.