This　paper　presents　a　high　power　widely　tunable　frequency-doubled　semiconductor　disk　laser　emitting　at　490　nm　wavelength.　The　laser　utilizes　a　specially　designed　gain　chip　with　widened　gain　spectrum　at　the　center　wavelength　of　980　nm,　along　with　an　anti-resonant　microcavity,　to　extend　the　tuning　range　of　the　wavelength.　A　type-I　phase-matched　5　mm　length　LBO　crystal　is　used　as　the　nonlinear　crystal,　and　a　fused　quartz　birefringent　filter　(BRF)　is　introduced　to　polarize　the　fundamental　emission　and　narrow　the　linewidth　of　the　laser.　When　the　thickness　of　the　used　BRF　is　1　mm,　50.7　nm　tuning　range　of　the　980　nm　infrared　laser　is　performed.　A　maximum　output　power　of　5.36　W　of　the　frequency-doubled　490　nm　blue　laser　is　achieved,　and　the　optical-to-optical　conversion　efficiency　from　absorbed　pump　power　to　the　blue　light　is　about　15.3%.　Meanwhile,　a　record　tuning　range　of　21.5　nm　of　the　blue　laser　is　realized.　The　measured　M2　2　factors　of　the　blue　laser　are　1.00　in　the　x-direction　and　1.04　in　the　y-direction,　respectively.　(c)　2024　Optica　Publishing　Group　under　the　terms　of　the　Optica　Open　Access　Publishing　Agreement