| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the size of a device and to improve outgoing light quantity efficiency relative to excitation light quantity, while maintaining the advantages of an optical fiber laser device, such as superior light-condensing characteristics and thermal stability in output and lateral mode are maintained. SOLUTION: For an optical fiber laser device in which an optical fiber 1 comprises a core 2 having laser activation material and a clad 3 surrounding the core and laser light is outputted from an optical fiber end part, when the core is supplied with excitation light, the optical fiber is surrounded with an optical medium 4. When the optical medium 4 is viewed cross-sectionably with respect to the optical axis of the optical fiber, a plurality of optical axes of optical fiber are included in the optical medium. The refractive indices of the clad 3 layer of the optical fiber relative to excitation light increase as proceed from the outer most part of an outer layer to a border with the core, so that the scattering loss at an interface between the clad 3 and the optical medium 4 is prevented.</p> |
