ARRANGEMENT OF OPTICAL ELEMENTS FOR FOCUSING APPROXIMATELY COLLIMATED BEAMS

摘要

A beam focuser for focusing an entrance bundle of approximately collimated beams around an optical axis in a focus area around a focal point. Along the optical path from the light inlet to the light outlet, a first axicon with an axicon angle, and subsequently a second axicon with the same axicon angle are arranged on the inlet side, and an imaging optical system is arranged on the outlet side. The first and second axicon are disposed mirror-symmetrically along the optical axis. The imaging optical system has a focal point which faces the outlet side of the beam focuser.

主权项

1. A beam focuser for focusing an entrance bundle of collimated beams around an optical axis in a focus area around a focal point, the beam focuser comprising:
a first axicon disposed inlet side with an axicon angle; a second axicon with the same axicon angle; and an imaging optical system arranged outlet-side and arranged in succession, centered along an optical axis, wherein the first and second axicon are arranged mirror-symmetrically along the optical axis, wherein a focal point of the imaging optical system faces the outlet side of the beam focuser, and wherein on a plane surface of the first axicon and on a plane surface of the second axicon a diffractive optical element is arranged, which transmission function is selected such that a group velocity dispersion and optionally higher-order dispersions of an ultrashort laser pulse are minimized along the beam path by the beam focuser.