Laser light emission across a wide bandwidth emission spectrum is enabled in a laser amplifier equipped with solid gain media. The laser amplifier is equipped with: a resonator; a plurality of solid gain media, having fluorescent spectra that a least partially overlap with each other, provided within the resonator; and pumping means, for pumping the plurality of solid gain media. The entire fluorescent spectrum width of the plurality of solid gain media is greater than the fluorescent spectrum width of each solid gain medium.