| 摘要 |
<p>A grating (12) is induced in the core (14) of a hydrogen-loaded high-germanium-content optical fiber (10) using near-UV (275 nm-390 nm) laser light (40). An interference pattern is generated at the core (14) using a molded polymer phase mask (30) with a square wave surface relief pattern (34). The light (40) is directed through the phase mask (30), through a protective fiber coating (18), through the cladding (16), and into the core (14). The phase mask (30) generates an interference pattern with a period half that of the surface relief pattern (34). Index of refraction changes occur at the bright fringes of the interference pattern, thus creating the grating. Advantages over existing mid-UV technology include lower fabrication costs for phase masks, simplified grating induction since fiber coatings do not need to be removed, and reduced infrared absorption caused by grating formation in the fiber.</p> |
