UV laser source implementing an IR pump laser with multi-element ridge waveguides

Biomedical optics applications of advanced lasers and nonlinear optics

“…Conventional UV diode laser systems suffer from limitations in power and spatial mode quality, while nonlinear conversion from the near-IR laser sources in bulk media is very inefficient for CW operation and often hard to maintain for day-to-day operations. 37 Aller et al (AdvR, Inc.) proposed a new device based on a two-part magnesium oxide-doped lithium niobate (MgO:LM) waveguide to enhance nonlinear optical conversion efficiency from the near-IR to the UV. The first section of the waveguide was periodically poled to optimize for second-harmonic generation from 1064 to 532 nm, and the second was adjusted for sum frequency generation of the fundamental and second harmonic to generate UV light at the 355-nm wavelength.…”

“…The lifetime was evaluated, and continuous nondiminishing performance was demonstrated for thousands of hours. 37 For deep-UV generation (200 to 266 nm), there is a distinct lack of commercially available crystals for frequency conversion compared to beta barium borate or lithium triborate/cesium lithium borate crystals (for 266 and 355 nm, respectively). Borate crystals have many of the properties required for deep-UV frequency conversion including an acentric structure, low-UV absorption, reasonable nonlinear coefficient, and a moderate birefringence.…”