Vertical-Cavity Surface-Emitting Lasers (VCSELs) are very attractive to high power light sources owing to the
advantageous configuration of two-dimensional arrays and being free from catastrophic optical damage. Although oxideconfined
VCSELs have been employed in most of applications with VCSELs, ion-implanted VCSELs have a potential to
be the better light sources for high power applications. In spite of the fact, the detailed characteristics of the ionimplanted
VCSELs had been researched only in ten milliwatt-class output power. Here we report on a high power
VCSEL-array with proton-implanted current apertures. A peak output power of over 40 W under short-pulse operation
has been achieved. This is the first demonstration of ten watt-class output power for ion-implanted VCSELs.
High Power Laser Diode (LD) modules are widely used as high-brightness light sources for pumping solid-state lasers
and for direct diode laser processing utilizing a compact feature. The LD bars installed in modules are required with
higher output power, efficiency and beam quality. We have optimized the LD bar structure for high output power and
efficient operation. The water-cooled heat sink has been designed for excellent thermal performance as well as long-term
stable cooling performance. We have also developed the thermal expansion controlled assembly technique to suppress
the "smile". As a result, we have achieved an output power of over 200 W and a conversion efficiency of 58% from 940
nm LD bars under continuous wave (CW) operation with very low smile of 0.8 μm.
Long life, high power and high repetition frequency 2D laser diode (LD) arrays are needed for pumping solid state lasers. The reliability of AlGaAs/GaAs high-power lasers has been studied. Over 1 X 10<SUP>9</SUP> operation shots in 4-stack 2D LD arrays with 350 W peak output power and over 1 X 10<SUP>13</SUP> shots in single-stripe laser diodes with 2.3 W peak output power have been obtained. 2D LD arrays of 3.5 kW (emitting area 3.2 cm x 1.0 cm), 2.5 kW (emitting area 1.0 cm x 1.0 cm) and 2.2 kW (emitting area 6.5 cm x 0.12 cm) were demonstrated under quasi continuous wave operation.