Optical apparatus, methods of forming the apparatus, and methods of using the apparatus are disclosed herein. In one aspect, an optical apparatus may include a substrate, an on-substrate microlens coupled with the substrate to receive light from an off-substrate light emitter and focus the light toward a focal point, and an on-substrate optical device coupled with the substrate proximate the focal point to receive the focused light. Communication of light in the reverse direction is also disclosed. Systems including the optical apparatus are also disclosed.