Present Status of SPring-8 Insertion Devices.

According to the general policy, namely, the pursuit of pure radiation without any unreasonable heat load, the construction of various insertion devices has been scheduled at SPring-8. Most of them are of the in-vacuum type, which makes it possible to realize short-period devices, so that the fundamental of undulator radiation may be obtained in the hard X-ray region. In addition, undulator radiation in the soft X-ray range down to 100 eV is available by introducing helical or figure-8 devices having low on-axis power density, which is very beneficial for the optics, gratings or mirrors. A brief overview of the insertion devices at SPring-8 is presented with the initial commissioning results.