| 摘要 |
PURPOSE:To miniaturize the whole device by forming a connecting optical system by a rod lens having a plane on its laser element side and a convex face on the other end on the optical fiber side and reducing the refractive index of the rod lens at almost the square distribution of distances from the center. CONSTITUTION:The laser module having an optical isolator is arranged between a laser element 1 and an optical fiber 9 and an optical system 30 for converging light projected from the laser element 1 and making the light incident on the optical fiber is formed by the rod lens 20 having a plane on one end of the laser element side and a convex face on the other end of the optical fiber side. In this case, the rod lens 20 is set up so that its refractive index is reduced at almost the square distribution of distances from the center. Namely, optical length for inserting the optical isolator is secured by the rod lens 20. Since the optical length for inserting the optical isolator can be set up only by one lens, the whole device can be miniaturized. |
