| 摘要 |
PROBLEM TO BE SOLVED: To generate a pulse energy having a peak intensity larger than those achieved with a single mode (SM) fiber, by increasing a capacity for accumulating energy in an optical fiber amplifier before starting undesirable non-linearity and gain saturation. SOLUTION: The optical amplifier has a fiber oscillator 10 serving as a laser source, which generates an input beam having a mode close to diffraction limit; a multiple mode fiber amplifier 12; a mode converter 14; and a pump source 20. The mode converter 14 receives an input beam, converts a mode of the input beam so as to conform to a basic mode of the multiple mode fiber amplifier 12, and generates a mode-converted input beam to be inputted to the multiple mode fiber amplifier 12. The pump source 20 optically pumps the multiple mode fiber amplifier 12, and generates a strong output beam which is intrinsically amplified by the basic mode. COPYRIGHT: (C)2007,JPO&INPIT |
