title: Single aspherical lens for deastigmatism, collimation, and circularization of a laser beam.
abstract: An astigmatic and elliptically diverging laser beam generated by a gain-guided laser diode can be converted into a collimated and circular beam with a single specially designed lens. The designed lens also corrects for the astigmatism present in the laser diode. The input surface of the lens has a different concave and convex aspherical profile in the transverse and the longitudinal direction, respectively, for astigmatism correction. The output surface possesses a convex aspherical and a straight profile in the transverse and the longitudinal direction, respectively, for collimation and circularization of the final output laser beam.
authors.affiliation: Metrology Laboratory, School of Mechanicaland Production Engineering, Nanyang TechnologicalUniversity, Singapore. mxqzhou@ntu.edu.sg
authors.forename: X Q
authors.initials: XQ
authors.lastname: Zhou
authors.forename: B N
authors.initials: BN
authors.lastname: Ann
authors.forename: K S
authors.initials: KS
authors.lastname: Seong