| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an optical fiber that increases a mode field diameter, while maintaining a value of a bending loss to be not more than that having no problem in practical use, and also turns a cutoff wavelength into a short wavelength side. <P>SOLUTION: The optical fiber 1 is equipped with: a core 10; a clad 20 formed around the core 10; and a hole area including a plurality of holes formed to extend in a shaft center direction of the core 10 in the clad 20. The hole area has a first hole area 22 including a plurality of holes 220 formed in the periphery of the core 10 and a second hole area 24 formed in the periphery of the first hole area 22 and including a plurality of holes 240. The optical fiber is provided such that the number of the holes 220 per unit cross section of the first hole area 22 is smaller than that of the holes 240 per unit cross section of the second hole area 24. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
