But over the past decade, scientists were unable to effectively enhance the brightness of ultraviolet light, due to the "phase mismatch" problem. Because infraredextreme ultraviolet light run at different phase velocities, resulting in low up-conversion yield of EUV beam. Chen’s solution was to use a small iris to change the photon phase, resulting in a bright attosecond EUV light.

Chen＇s lab found accidently that by adjusting the aperture size of the iris they could precisely control the EUV’s bandwidthcentral wavelength. This was the breakthrough everyone had been looking for, since the simple iris actually increased the up-conversion yield of 18 nm more than one order of magnitude because of the phase mismatch between the infrared raythe converted EUV light.

EUV has been widely used in scientific research in such areas as materials, electronics, biology, medicine, physics, chemistry, chemical engineering, geology, archeology, energy, environmental protection,micro-mechanics. Especially, EUV has been the key technology for the next generation high-volume manufacturing of semiconductor devices. The table-top EUV light source will definitely make gr