Free-space to single-mode collection efficiency enhancement using photonic lanterns

Opt Lett. 2013 Sep 15;38(18):3554-7. doi: 10.1364/OL.38.003554.


We demonstrate single-mode collection efficiency enhancement for free space optical systems using a photonic lantern to collect scattered infrared light from diffuse objects at far- and near-field distances. A single-mode collection efficiency improvement of ∼8 dB is demonstrated in the near-field region relative to standard single-mode fiber. The insertion loss properties of the photonic lantern are also analyzed, and an additional insertion loss penalty is observed for near-field distances when the transmitted beam is collimated. The photonic lantern can be used for coherent detection systems such as light detection and ranging and free-space optical communication with improved collection efficiency and nearly perfect mode matching.