| 摘要 |
In an optical fiber or other light guiding body is utilized that the diffusion properties of fluorine, which reduces the refractive index, are strongly changed, if also a doping with phosphorous is made, to change the refractive index and hereby the light guiding properties. In for example a single mode fiber (1) thus locally an additional waveguide core (9) can be created parallel to the already existing waveguide core (3), by providing in parallel to the ordinary core (3) an activatable region (5) having substantially the sane dimensions as the existing core and having suitable dopings of fluorine and phosphorous. This can be utilized to produce an optical filter element If the optical fiber is D-fiber, a sensor element can be produced. Furthermore, for suitable concentrations of these dopants and of germanium an existing waveguide core can be erased by a heating operation. |
