A team at the University of Central Florida in Orlando has demonstrated a differential-pumping scheme for a xenon capillary-discharge plasma source that enables the device to produce 11.3- and 13.5-nm light in a full hemisphere. The previous uniform-pressure configurations displayed a limited angle of emission.The new device, which the team described in the Sept. 20 issue of Applied Optics, uses the capillary as the differential-pumping tube, so emission occurs near the surface of the structure. The light source may find a place in extreme-UV imaging applications.