Patent ID: 6594289
Filing Date: 2003-07-15
Classification: H01S

Abstract:
A tunable laser source apparatus including an external cavity, the apparatus comprising:a semiconductor laser including a reflection surface formed on one end, a surface with an anti-reflection film formed on the other end, and an active layer extending from said reflection surface toward a tip portion, a window region formed between the tip portion of said active layer extending toward said surface with the anti-reflection film of said semiconductor laser and said surface with the anti-reflection film of said semiconductor laser, and wavelength selecting means for selecting from laser light emitted from said semiconductor laser through said surface with the anti-reflection film and feeding laser light of a desired wavelength back to said semiconductor laser through said surface with the anti-reflection film, wherein said window region enables the laser light of the desired wavelength fed back from said wavelength selecting means to be coupling thereon, while dilating the beam size of a portion of the laser light which is reflected from said surface with the anti-reflection film to reach said tip portion film.