Patent ID: 6842471

Claim:
A semiconductor laser device comprising: a semiconductor substrate; and a layer structure formed thereon, comprising consecutively as viewed from the bottom: a lower cladding layer; an active layer; an upper cladding layer; first and second current blocking layers; and an external cladding layer, said layer structure configuring a laser cavity having an emission facet and a rear facet, said first and second current blocking layers having compositions different from each other, said first and second current blocking layers having aligned first openings to form a current injection area for injecting operating current into said active layer, said second current blocking layer having a second opening, through which said external cladding layer contacts said first current blocking layer, in a vicinity of said emission facet to form a current non-injection area for blocking said operating current, and said external cladding layer having a refractive index substantially equal to a refractive index of said first current blocking layer.