Abstract
We developed a wafer-level integration process for multiple-wavelength laser diodes. This integration process allows highly accurate and proximal alignment of emission spots, as well as high mass-productivity. Using this process, we fabricated blue/red and red/infrared two-wavelength laser diodes. In these laser diodes, the distance between two emission spots was approximately 3μm. Furthermore we fabricated blue/red/infrared three-wavelength laser diode whose emission spots were aligned within 10μm distance. Such a short spot distance allows the optical components of the pickup to be substantially simplified.