InGaAlAs/AlGaAs/GaAs strained double quantum well (DQW) linear array diode lasers with asymmetric wide waveguide have been successfully fabricated by pulse anodic oxidation process upon molecular beam epitaxy (MBE) material growth, high efficiency and high power quasi-continuous-wave (QCW) output has been realized at 808 nm wavelength. The pulse anodic oxidation process is used to etching and insulating film preparation in QCW device process with electrolyte solution of 4∶20∶1∶1 ratio of glycol∶deionization water∶phosphoric acid∶2% hydrochloric acid. The fill factor of the prepared linear array is about 72.7%, the threshold current and slope efficiency of the prepared devices are 24 A and 1.25 W/A respectively under QCW operation condition of 100 Hz repetitive frequency and 200 μs pulse width, a maximum electrical-optical conversion efficiency of 51% has been achieved.