Stony Brook, N.Y.-based Photonics Industries International Inc. has generated what it says is the highest power at UV wavelength ever reported for the Q-switched Nd:YLF laser third-harmonic output. The company created 7.1 W of single transverse mode UV output at 351 nm, with a 3-kHz repetition rate and 200-ns pulse width, and an overall conversion efficiency of 46 percent. Originating from the Q-switched Nd:YLF's 15.5-W power at 1053 nm, intracavity second- and third-harmonic generations using LBO crystals produced 5 W of power at 1 kHz and 7.1 W at 3 kHz. The company plans to use this development for stainless steel marking and machining applications.