STRUCTURE OF FORMED END OF OPTICAL FIBER

摘要

PURPOSE:To stabilize optical output characteristics of an LD module by forming an end surface including at least the end surface of an optical fiber strand of a center element out of a pair of butted end surfaces as an inclined surface. CONSTITUTION:An optical fiber core 11 is held on the center and the end surface 12a of the center element 12 and the end surface 13a of a rod-like lens 13 for leading light into the core 11 or out from the core 11 are butted and fixed with an optical adhesive after butting their optical axes each other. A pair of the butted end surfaces 12a, 13a including the end surface of the optical fiber strand are partially inclined in the same direction. Since the LD coupling efficiency with reflected and returned light to be generated by respective end surfaces 12a, 13a due to gaps generated between the center element 12 and the lens 13 is remarkably changed because of the change of the refractive index of the optical adhesive or the thermal expansion of the member, the characteristics of the LD module can be stabilized.