Fig. 4: Beam quality measurement.
From: Massive-scale spatial multiplexing of multimode VCSELs with a 3D-printed photonic lantern
a Self-interference experimental setup. M.O microscope objective, ND neutral density filter, BS beam splitter. 7-MM PL, 19f-MM PL, and 37-MM PL: b measured intensity, complex field, (c) M2, and ideal fiber coupling at different currents per VCSEL source (6–11.2 mA).
