Patent ID: 6671444
Filing Date: 2003-12-30
Classification: G02B,G02F,H01S

Abstract:
An optical fiber, which generates white light by means of the nonlinear phenomenon in the wavelength bands at both sides of a pumping optical pulse that is input, wherein said optical fiber is formed by covering the surroundings of a core by a first cladding, which is lower in refractive index than said core and covering the surroundings of said first cladding by a second cladding, which is greater in refractive index than said first cladding but lower in refractive index than said core, by having in at least part of the length direction of said optical fiber, a portion in which the wavelength dispersion gradient for the wavelength band at the shorter wavelength side of the wavelength of the pumping optical path is positive and the wavelength dispersion gradient for the wavelength band at the longer wavelength side of the wavelength of the pumping optical path is negative, by having in at least part of the length direction of said optical fiber, a zone in which the wavelength. dispersion for the wavelength of the pumping optical pulse varies from anomalous dispersion to normal dispersion from the side at which the pumping optical pulse is made incident towards the side at which light exits, and by by having a transmission loss of the optical fiber that is 10 dB/km or less for light of a wavelength in the vicinity of 1.4 &mgr;m, having a polarization-maintaining mechanism that maintains the polarization of the light that propagates through said optical fiber, wherein the polarization-maintaining mechanism is formed by having a pair of stress-applying parts inside the second cladding so as to sandwich the core, wherein the shortest distance between the pair of stress-applying parts is 2.3 times or more the mode field diameter for the wavelength of the pumping optical pulse.