Abstract: The present invention provides an optical amplifying device which can be easily downsized, increased in output, and stabilized. An optical amplifying device 1A includes an optical amplifier 10A and an energy supplier 30. The optical amplifier 10A includes an optical amplifying medium 11 and a transparent medium 12. The energy supplier 30 supplies excitation energy (for example, excitation light) to the optical amplifying medium 11. The optical amplifying medium 11 is supplied with the excitation light to amplify light and output it. To-be-amplified light passes through the transparent medium 12 in the optical amplifying medium 11 a plurality of times. The transparent medium 12 can propagate the to-be-amplified light, for example, zigzag inside.

Abstract: An optical element 20A which is composed of a light transmission characteristic medium, that has a refractive index higher than a refractive index of air, the optical element causes an incident laser beam to be propagated inside while reflecting the laser beam by a wall surface 20a a plurality of times, the optical element includes an incident window 21 which is located in a part of the wall surface 20a, that is for allowing the laser beam to be incident, an emitting window 22 which is located in a part of the wall surface 20a, that is for allowing the laser beam propagated inside to be emit, and wavelength dispersion compensating units 31 and 32 which are integrally located in parts of the medium, the wavelength dispersion compensating units compensate for wavelength dispersion by causing the laser beam to be transmitted or reflected at least twice.

Abstract: The present invention provides an optical amplifying device which can be easily downsized, increased in output, and stabilized. An optical amplifying device 1A includes an optical amplifier 10A and an energy supplier 30. The optical amplifier 10A includes an optical amplifying medium 11 and a transparent medium 12. The energy supplier 30 supplies excitation energy (for example, excitation light) to the optical amplifying medium 11. The optical amplifying medium 11 is supplied with the excitation light to amplify light and output it. To-be-amplified light passes through the transparent medium 12 in the optical amplifying medium 11 a plurality of times. The transparent medium 12 can propagate the to-be-amplified light, for example, zigzag inside.