| 摘要 |
PROBLEM TO BE SOLVED: To improve the productivity by irradiating an area which contains a core with a high refractive index on an end surface of the optical waveguide with specific laser light and forming a hole only at the part of the core. SOLUTION: The end surface of the optical waveguide is irradiated with the laser light and in this case, the focus of the laser light is made to deviate from the end surface of the optical waveguide, thereby forming an irradiation range including the core and its periphery. Then the 3rd higher harmonic of Nd-YAG laser is used as the laser light. When the energy of the laser light is gradually increased, vaporization starts at the part of the core to form the hole at the part of the core. Thus, the focus position of the laser light need not be adjusted to the end surface of a glass substrate and is properly determined, and an area including the core to some extent is irradiated with the laser light; and the energy of the laser light is gradually increased thereafter and the intensity of the laser light is determined when the vaporization starts at the part of the core. |
