The first integrated 1310 nm wavelength MEMS-VCSELs have been reported in this issue of Electronics Letters by collaborating researchers in the US. Optimised specifically for swept-source optical coherence tomography (SS-OCT) applications, these MEMS-VCSELs can also be continuously tuned over 150 nm, which is the largest tuning range of any surface emitting diode lasers at any wavelength.“MEMS-VCSELs have previously demonstrated speed and coherence length advantages for SS-OCT, but questions remained as to whether MEMS-VCSEL tuning range could compete with widely tunable external-cavity lasers,” said Dr Vijaysekhar Jayaraman from Praevium Research who took the lead on the design and fabrication. “We believe that this work demonstrates for the first time that MEMS-VCSEL tuning range can be on a par with these other devices.”