High-power 735 nm GaAsP/AlGaAs laser diodes: reliability and beam characteristics

Summary form only given. The increasing interest for light sources in the spectral region between 710 nm and 780 nm is due to special medical applications, for example photodynamic therapy (PDT), which requires high-brightness light sources in this spectral region. The most promising light sources for this purpose are high power diode lasers. In this paper results for high power diode lasers applying tensile-strained GaAsP quantum wells embedded in AlGaAs were presented. These diode lasers having a large optical cavity (LOC) structure show a high wall-plug efficiency larger than 50% and a small vertical divergence of about 25/spl deg/ FWHM. The long-term behavior of broad area lasers is shown and the beam characteristics of broad area lasers and tapered lasers are compared.