| 摘要 |
PURPOSE:To manufacture a laser element at a high yield, which is able to oscillate in a single longitudinal mode by a method wherein ranges of a standardized coupling coefficient kL proportional to a depth of a diffraction grating, the length of a resonator, and the like, and a reflectance of an end face are optimized. CONSTITUTION:A diffraction grating and a waveguide path structure both uniform in a direction of a resonator axis are formed, one of end faces is made to be 30% by optical power in reflectance and the other end face is made to be 5-15% in reflectance, and that the product kL of a coupling coefficient k and the length L of a resonator is determined so as to satisfy an inequality, 0.4<=kL<=1.3. When a reflectance of an end face and the product kL of a coupling coefficient k and a resonator length L are determined, a light intensity inside a laser element is taken into consideration and also a mode instability due to a hole burning phenomenon which occurs in a direction of a resonator axis is taken into consideration. |
