Abstract: VCSEL apparatus having a substrate, a solid-state gain medium, a reflective mirror on one side of the medium, a movable reflective mirror on an opposite side of the medium, and a mechanism configured to move the movable mirror to tune a characteristic wavelength. Also described is a VCSEL apparatus having a silicon substrate having a slot therethrough and electrical connections formed on a first face, a substrate having VCSELs thereon and mounted across the slot and electrically connected to the electrical connections on the silicon substrate, and a glass substrate affixed to a second face of the silicon substrate. Also described is a VCSEL apparatus having a graded-index lens array having GRIN lenses mounted adjacently in a staggered arrangement, a PCB mounted to the lens array, and VCSEL chips mounted adjacently on the PCB and arranged so as to emit laser light through the lenses.