Patent ID: 6179830
Filing Date: 2001-01-30
Classification: A61B,A61C,B23K,G02B

Abstract:
A laser probe for organic hard issue, detachably attached to a tip end of a handpiece, for guiding laser light emitted from a laser light source to the handpiece by laser light guiding means, the laser probe comprising an optical fiber having a core and a clad formed on an outer peripheral face of the core, and wherein:the optical fiber has a refractive index distribution in which a refractive index n1c of a center portion of the core is lower than a refractive index n1 of a portion of the core surrounding the center portion,an intermediate layer is formed between the core and the clad,the refractive index n3 of the intermediate layer is lower than the refractive index n2 of the clad,the refractive index n2 of the clad is lower than the refractive index n1c of the center portion of the core,the optical fiber has a refractive index distribution in which the refractive index is sharply changed at an interface between the core and the intermediate layer and an interface between the intermediate layer and the clad,the core of the optical fiber has a diameter of 0.2 mm to 3.0 mm,the laser light has a wavelength of 1.0 .mu.m to 5.5 .mu.m, an output energy of 1 mJ to 2,500 mJ, a pulse width of 1 ns to 9 ms, and a pulse cycle of 1 pps to 200 pps,the core of the optical fiber is made of SiO.sub.2 to which an additive selected from the group consisting of GeO.sub.2, TiO.sub.2, P.sub.2 O.sub.5 and Al.sub.2 O.sub.2 is added in a concentration distribution in which the additive concentration of a peripheral portion of the core is lower than the additive concentration of the center portion of the core,the intermediate layer of the optical fiber is made of SiO.sub.2 to which one selected from the group consisting of B.sub.2 O.sub.5 and fluorine is added, andthe clad of the optical fiber is made of single SiO.sub.2.