Multiwavelength Blue Light Source Based on MgO : PPLN SHG Using Vertically Stacked Grating-Coupled Surface-Emitting Lasers

In this letter, we present the first experimental results of frequency doubling the output of vertically stacked grating coupled surface-emitting laser/dual-grating reflector devices with different emitting wavelengths. We used a multigrating 5% magnesium-oxide-doped periodically poled lithium niobate (MgO : PPLN) crystal as the nonlinear conversion medium. In pulse operation, 0.6 W of multiwavelength total second-harmonic peak power was obtained. The individual emitter output is focused into each channel of the crystal by diffractive beam shaping optical element array to minimize the footprint area of the whole setup.