In the current ATR Uptodate, we have put together a special issue on the optical micro-devices developed by ATR Adaptive Communications Research Laboratories (ACR). Recently, the optical and electrical devices that ACR has constructed from III-V compound semiconductors, such as those using GaAs, have become recognized as attractive key technologies for application to lightwave and wireless communication systems that offer large capacity and ultra-high-speed performance. At the same time, we are witnessing the emergence of a ubiquitously networked society, which will surely make drastic changes in our lifestyle. Many of the systems that will be in demand to meet the needs of this future ubiquitous society will require new functional devices. Such advanced systems cannot be developed by conventional concepts of device design and materials usage.
　　A wide variety of ACR devices-lateral p-n junction devices, 2D microcavity lasers, quantum dots, and Micro-origami, to name a few-each has its own unique features based on a long history of expertise and innovation in device manufacturing techniques. In spite of ACR being a small but elite team, it has been working tirelessly since its establishment to produce flexible, large-capacity communication links, and the ACR team is determined to keep up its challenging spirit by creatively using new functional materials. We can expect that the refined manufacturing abilities of ACR will bring about fantastic and highly useful devices for constructing platform systems of the coming ubiquitous society, including ad hoc networks and optical wireless systems. To achieve its goals, the ACR team will surely need to form many collaborative arrangements outside of ATR, with both domestic and overseas organizations.
　　Finally, we are extremely grateful to Professor Hasegawa, Director of Research Center for Integrated Quantum Electronics, Hokkaido University, for kindly contributing to this issue as our guest author.

YAMAHATA Shoji
ATR UptoDate Editorial Staff