PURPOSE: To enable low-loss connection and to facilitate optical axis adjustment without offset at the time of fusing by increasing the strength of connection to optical parts without subjecting the end face of the optical waveguide to mirror finishing and perpendicular polishing.
CONSTITUTION: This optical waveguide 1 is formed as a flush type optical waveguide by providing a clad 51 on a glass substrate 4 with a core 3 and coating the surface of the core 3 with a clad 52. The refractive index nw of the core 3 is higher than the refractive index nc of the clads 51 and 52. Circular optical fiber insertion holes 21 and 22 for coupling light into the core 3 by being inserted with the optical fibers are formed at both ends of the optical waveguide 1. The insertion holes 21 and 22 penetrate the substrate 4 from the front surface of the optical waveguide 1 down to the rear surface of the substrate thereby parting the core 3. Both the holes 21 and 22 are bored perpendicularly to the front surface of the optical waveguide and the rear surface of the substrate. These holes 21 and 22 are formed by irradiation with a CO2 laser beam. A light signal is propagated between the optical fiber, the optical waveguide 1 and the optical fiber by the insertion of the optical fibers into the formed holes 21, 22.
HOSHINO HIROYUKI
ANDO YORIO
