500 mW tunable external cavity diode laser with narrow line-width emission in blue-violet region

A tunable external cavity diode laser (ECDL) system with narrow line-width emission at 410 nm is presented. Based on a commercially available laser diode and a Littrow arranged reflective holographic grating, a maximum output power over 500 mW with line-width of about 50 pm is achieved at the rated current. The power efficiency is over 85% and the threshold decreases over 20% compared to the free-running laser diode. Manual tuning range over 5 nm is achieved around threshold condition and over 2 nm at high injection currents up to 500 mA with side mode suppression ratio larger than 20 dB.