OPTICAL FIBER AND LIGHT GUIDE

摘要

An optical fiber comprising a core portion and, provided on the outer circumference thereof, a cladding portion of refractive index lower than that of the core portion, wherein the cladding portion in its interior is provided with four vacancies with a four rotational symmetry around the core portion so as to realize a zero dispersion wavelength of 900 to 1150 nm and a cutoff wavelength of 950 nm or less. Preferably, the cutoff wavelength is 900 nm or less. Accordingly, an optical fiber of single mode suitable for transmission of light of 900 to 1150 nm wavelength, and thus a light guide including the same, can be provided through easy productive operation at low cost.