MICROLENSES FABRICATED BY MELTING A PHOTORESIST ON A BASE LAYER

We report on the fabrication of novel refractive microlens arrays in p hotoresists, in particular on lenses with numerical apertures ranging from 0.1 to 0.3. A base layer technique is described that makes it pos sible to fabricate lower numerical aperture lenses in resist, compared with microlenses on glass substrates. The wave aberrations were measu red in a Mach-Zehnder interferometer. Diffraction-limited performance was achieved for a numerical aperture of 0.2 and a lens diameter of 27 0 mum.