| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide mode filtering in multiplex mode light guide, and to provide its selection method, a light guide amplifier using it, a semiconductor laser, and VCSEL. <P>SOLUTION: A mode filtering method has a structure, in which the refractive index to a lateral direction of the clad part of a multiplex mode light guide consisting of a core and a clad, and transmits only certain specific modes having a multiplex mode along a waveguide, by enlarging a reflectance only to a cross section directional wavelength of the certain specific modes, and lessening the reflectance to the other mode. If filtering or selection effect due to a periodical refractive index is applied to EDF, the semiconductor laser, VCSEL and the like, a high power single-mode amplifier that operates at a single mode and has high performance, a laser and the like can be manufactured while having a very large cross section, as compared with those of the conventional products. <P>COPYRIGHT: (C)2004,JPO</p> |
