Fresnel Zone Plate Array Fabricated by Maskless Lithography

This work reports the fabrication of Fresnel Zone Plates (FZP) by employing a maskless lithography tool based on direct laser writing. The target application areas in this work are to use a micro lens array (MLA) in a wavefront sensor, for optical aberrations quantification in human eye diagnostics or adaptive optical system. This last one is essential in astronomy applications in order to correct the aberrations introduced by earth atmosphere. The fabricated FZP generates illumination points with high contrast intensity in the focal plane, which is the purpose of the wavefront sensor. This high-contrast image suggests that the employed fabrication process is well controlled and it matches the design parameters.