title: Making fast cylindrical gradient-index lenses diffraction limited by using a wave-front-correction element.
abstract: A wave-front-correction element (WFCE) is produced to make a cylindrical Ag-ion-exchanged gradient-index (GRIN) lens with a high numerical aperture (0.53) diffraction limited (wave-front error, 0.02lambda rms). The wave-front aberrations of the cylindrical GRIN lens are measured by a phase-shifting shearing interferometer, with a conventional microscope objective used as a compensation lens. The continuous surface relief of the WFCE is produced by a lithographic process. The wave-front-corrected GRIN lens is applied to collimate the strongly divergent light (57 degrees full diverging angle measured at 1/e(2) of maximum intensity) emitted by a high-power diode laser. The power irradiated into a full angle of 2 mrad can be enhanced by a factor of 1.8 with the WFCE.
authors.forename: A V
authors.initials: AV
authors.lastname: Pfeil
authors.forename: B
authors.initials: B
authors.lastname: Messerschmidt
authors.forename: V
authors.initials: V
authors.lastname: Blümel
authors.forename: U
authors.initials: U
authors.lastname: Possner
authors.forename: T
authors.initials: T
authors.lastname: Possner