| 摘要 |
PURPOSE:To obtain an optical transmission wire of good optical transmission characteristics and high reliability by providing an elastic resin thin layer of a refractive index smaller than those of core and clad between the core and clad. CONSTITUTION:Between core glass 1 of phosphate glass or the like and clad glass 3 of silicic acid base or the like is provided a thin layer 2 of epoxy resin or the like being elastic material of a refractive index smaller than that of the glasses 1, 3 as a buffer material. This constitution causes the stress generated owing to the difference in the coefficient of thermal expansion of the glasses 1, 3 of the case of transmitting light of large numerical aperture by increasing the difference in the refractive index of the glasses 1, 3 to be absorbed in the good layer 2. Hence, the degree of freedom in selection of the compositions of the glssses 1, 3 is increased and the optical transmission wire of good optical transmission characteristics and high reliability may be obtained. |
