Abstract: Ununiformity of a light intensity of a laser beam is appropriately reduced. An optical element receives a laser beam having a light intensity distribution and provides wavefront aberration of the received laser beam in a first direction orthogonal to a traveling direction larger than a diffraction limit, and provides wavefront aberration of the received laser beam in a second direction orthogonal to the traveling direction and the first direction equal to or smaller than the diffraction limit.

Abstract: An object of the invention is to provide a laser line-generator that generates a straight line with the both end portions as bright as the central portion, and a laser line-generator module that integrates the laser line-generator with a laser light source. A columnar transparent medium has an entrance boundary surface 10 for taking in laser light and an exit surface 20 for emitting the taken laser light linearly. At least one of the entrance boundary surface 10 and the exit surface 20 is composed of a curved surface, and a curve forming the curved surface includes two or more inflection points F.