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There is provided an end-pumped vertical external cavity surface emitting laser (VECSEL) in which a pump laser beam is incident on a laser chip at a right angle. In the external cavity surface emitting laser, a laser chip package is provided with a laser chip emitting light at a first wavelength by optical pumping, an external mirror is spaced apart from a top surface of the laser chip package to transmit a portion of the light emitted from the laser chip to the outside and to reflect the remainder to the laser chip, a heat sink is coupled to the bottom surface of the laser chip package to discharge heat generated by the laser chip, and a pump laser faces a bottom surface of the heat sink to emit pump light at a second wavelength perpendicular to the laser chip.

We have optimized a resonant gain structure of a 920 nm vertical external cavity surface emitting laser. We found that a long saturated carrier lifetime in shallow quantum well (QW) under a high injection level restricts the laser performance. An insertion of non-absorbing laser in the middle of barrier layers with multi QWs is effective to reduce the saturated carrier lifetime and, therefore, to enhance the laser performance. With the optimized laser structure, which has 10 periods of triple In 0.09 Ga 0.91 As QWs located at the anti-standing wave optical field with A l0.3 Ga 0.7 As non-absorbing layers in the middle of GaAs barrier, we achieved 4.9 W operation at 920nm. Subsequently blue laser was achieved by employing an intra-cavity frequency doubling crystal LBO. As a result, we demonstrated 2 W single transverse mode operation in blue (460 nm) with a 20 W pump laser power. The conversion efficiency from 808 nm pump laser to the blue laser is measured to be 10 %.