| 摘要 |
<p>Optical fiber designs are depicted with a core having an alpha profile inner portion (55) and a steep vertical step (56a) between the core and a cladding with no shoulder, referred to herein as a truncated core. A further aspect of this invention can include a trench (56c) between the truncated core and cladding (56d). In this embodiment, the core performs as not only as the primary light guiding structure, but now also functions essentially the same as that of a trench structure. Thus, what was formally a trench can now be much less negative or even positive. Another embodiment of the present invention includes an optical fiber having a truncated core with the addition of a ledge or shoulder between the core and vertical step, followed directly by a cladding.</p> |
