Tapered　diode　laser　with　ridge　waveguide　was　introduced　and　formed　through　etching　the　wafer　with　asymmetrical　waveguide　structure　and　double　quantum　walls.　In　the　laser,　the　negative　effect　of　p-cladding　layer　was　decreased　and　the　vertical　divergence　angle　was　reduced.　The　high　brightness　power　is　arrived　on　account　of　the　combination　of　the　ridge　waveguide　and　the　taper　waveguide.　In　experiment,　the　laser　delivers　976　nm　and　4　W　CW　at　7　A　current.　The　slow　direction　beam　quality　and　the　fast　direction　beam　quality　are　measured　of　1.593　mm·mrad　and　0.668　mm·mrad,　respectively.　©　2016,　Science　Press.　All　right　reserved.