| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an optical fiber which allows single mode transmission at a wavelength of 1,550 nm, includes a large effective core cross-sectional area, keeps an appropriate bending loss and is suitably used for a large capacity optical transmission. <P>SOLUTION: The optical fiber 10 includes the effective core cross-sectional area of 175μm<SP>2</SP>or larger at the wavelength 1,550 nm, the bending loss of 10 dB/m or smaller at a diameter of 20 mm, a cutoff wavelengthλc of 1,550 nm or smaller, and includes a first core 11 which is located at the center and includes a higher refractive index than that of a clad 13, a second core 12 which is formed at the outer periphery of the first core 11 and includes a smaller refractive index than that of the clad 13, and a sub medium section which includes a lower refractive index than that of a main medium section and a main medium. The sub medium section includes a plurality of first sub medium sections 15 disposed along the outer periphery of the first core 11, and a plurality of second sub medium sections 16 disposed along the outer periphery of the first core 11 and outer side of the first sub medium sections 15. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
