Regenerative amplifier with internal telescope of cylindrical lenses

摘要

The device has an optical switching element (9) with rectangle shaped cross-section approximately at right angles to beam direction. A beam shaping lens (7) is provided in beam path before the optical switching element. A laser beam of roughly round cross section passes through the rectangle shaped optical switching element and converts to approximately elliptical beam cross-section. Independent claims are also included for the following: (A) Amplification device; and (B) Ultrashort pulse laser.