OPTICAL FIBER AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To enable the multiple wavelength multiplex by expanding the amplification band to the longer wavelength side. SOLUTION: An optical fiber amplifier excites Er<3+> ions on an Er<3+> ion-doped quartz optical fiber 3 by an exciting light at a longer wavelength band than 1.5 microns to form an inverted distribution between the I15/2 and I13/2 levels of the Er<3+> ions and an optical signal at the longer wavelength band than 1.5 microns inputted to the optical fiber 3 is amplified by the induced emission based on this distribution. In this case, the exciting light at the longer wavelength band than 1.5 microns uses an induced emission light produced from an exciting Er<3+> ion-doped quartz optical fiber 2.