Cover Story：Zhang L, Pan J, Zhang Z, Wu H, Yao N et al. Ultrasensitive skin-like wearable optical sensors based on glass micro/nanofibers. Opto-Electron Adv 3, 190022 (2020). 

Micro/nanofiber (MNF) is a kind of optical fiber that is dozens of times thinner than human hair. Due to its tight optical confinement, strong evanescent fields, excellent mechanical properties, and small bending radius, MNF offers outstanding advantages in highly sensitive optical sensing. Recently, Professor Lei Zhang and Professor Limin Tong in nanophotonics research group at the College of Optical Science and Engineering of Zhejiang University reported a highly sensitive skin-like wearable optical sensor based on MNF. The flexible polymer film-embedded MNF likes a nerve in the skin. When the MNF is subjected to external stimuli such as pressure, vibration, and bending, the optical signal output from the MNF changes accordingly. High-sensitivity sensing of weak pressure (0.1 Pa), high-frequency vibration (20 kHz), angle, sound and pulse is achieved by detecting light signals in real time. This "optical skin" sensor can not only be attached to human skin to monitor physiological indicators, but also integrate with gloves to sense the movement of the hand joints, enabling remote and precise manipulation of a mechanical hand. This research has opened up new avenues for the development of new tactile sensing systems and smart robots in the future.