Laser processing method to an optical waveguide
AssigneeNippon Sheet Glass Co., Ltd.
InventorsKeiji Tsunetomo, Tadashi Koyama
Life of this patent
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Abstract
In a method for forming a hole for fitting an optical fiber only at a core portion without having to precisely match or accord the focus of a laser beam with the end surface of an optical waveguide, when a laser beam is irradiated onto the end surface of the optical waveguide, the focus of the laser beam is turned away from the end surface of the optical waveguide and a region of the irradiation includes the core and the periphery thereof. Thereafter, the energy of the laser beam is increased step by step, and a few pulses thereof are radiated with the intensity fixed when ablation occurs at the core portion, so that the hole is formed only at the core portion.
Claims5
A laser processing method to an optical waveguide, comprising the steps of:
- forming a highly refractive core in which a light beam is to be transmitted in a substrate;
- making absorption characteristics of the core with respect to a laser beam superior to absorption characteristics of the substrate in proportion to a refractive index of the core;
- and radiating the laser beam onto a region, in which the highly refractive core is exposed, including the core at an end surface of the optical waveguide;
- wherein an intensity of the laser beam is set at a value more than a threshold value that is enough to cause fusion, evaporation or ablation to the core and less than a threshold value that is sufficient to cause fusion, evaporation or ablation to other portions of the region;
- so that a hole is formed only at a portion of the core exposed in the region.
Dependencies are inferred from the claim text.