Compact Blue Light Source by Single-Pass Second Harmonic Generation of DBR Tapered Laser Radiation

We demonstrate a continuous-wave 460-nm compact visible laser module having a footprint of 75 mm × 25 mm × 25 mm. This blue light source is achieved through single-pass second harmonic generation with a distributed Bragg reflector tapered diode laser as a single-frequency pump source at ~920 nm in a periodically poled MgO-doped lithium niobate crystal with a planar waveguide. The compact blue laser module reached an optical output power of 286 mW with the highest optical conversion efficiency of 11.6% at room temperature. The power stability of the blue light from the laser module is measured at an output power of 268 mW with a variation of ±3.5% during a period of 1 h.