Optical fiber coupling part and manufacturing method thereof
An optical fiber coupling part that reduces the difficulty in adjusting cores, minimizes coupling loss, and prevents optical characteristics from deteriorating. An optical fiber is fused to one end of a GRIN lens which includes a quartz glass containing one or more refractive index regulating substances selected from Sb 2 O 3 , Ta 2 O 5 , TiO 2 or ZrO 2 . Optical characteristics are not deteriorated because an adhesive is not used, and self-alignment effects facilitate adjustment of the cores of the GRIN lens and the optical fiber. Furthemore, coupling loss can be minimized by setting a refractive index distribution constant g of the GRIN lens within an appropriate range.
1. A method of manufacturing an optical fiber coupling part, comprising:
mixing a silicon alkoxide, an alcohol, an acid or a base as a solvent, and a refractive index regulating substance to make a wet gel, wherein the refractive index regulating substance includes tantalum, antimony and zirconium;
providing a concentration distribution of the refractive index regulating substance in the wet gel;
drying the wet gel to make a dry gel;
baking the dry gel to make a glass body;
spinning the glass body into a thread;
cutting the spun thread into a cycle length of ¼ as long as a zigzag cycle of a light propagated through the thread or a length that is an odd number times a length of ¼ of the zigzag cycle to make a GRIN lens; and
fusing an optical fiber to one end of the GRIN lens.