High-power　vertical-cavity　surface-emitting　laser　(VCSEL)　arrays　are　increasingly　utilized　as　light　sources　in　modern　lidar　and　three-dimensional　optical　sensing　systems　owing　to　their　strong　coherence　and　high　beam　quality.　In　this　article,　a　narrow-linewidth　in-phase　mode　output　VCSEL　array　is　demonstrated,　employing　a　droplet-shaped-mesa　and　evanescent　wave,　to　improve　the　coupling　efficiency　and　coherence.　The　maximum　coupling　efficiency　is　determined　theoretically　to　be　32.6%　with　a　77.3°　droplet　tip　angle,　exactly　twice　of　the　total　reflection　angle.　The　wavelength　redshift　rate　of　the　droplet-shaped-mesa　VCSEL　array　is　0.03　nm/mA,　which　is　30%　that　of　a　single　VCSEL.　The　full　width　at　half　maxima　(FWHM)　of　the　emission　spectrum　of　the　fabricated　1×2　VCESL　array　is　0.14nm,　which　is　32.5%　that　of　the　single　device.　Finally,　the　far-field　divergences　at　1/e2　peak　intensity　in　the　horizontal　and　vertical　directions　are　8.3°　and　8.6°,　respectively,　which　are　47.1%　and　46.6%　lower　than　that　of　a　single　VCSEL　device　of　the　same　size.　©　1983-2012　IEEE.