title: Chromatic control in coextruded layered polymer microlenses.
abstract: We describe the formation, characterization and theoretical understanding of microlenses comprised of alternating polystyrene and polymethylmethacrylate layers produced by multilayer coextrusion. These lenses are fabricated by photolithography, using a grayscale mask followed by plasma etching, so that the refractive index alternation of the bilayer stack appears across the radius of the microlens. The alternating quarter-wave thick layers form a one-dimensional photonic crystal whose dispersion augments the material dispersion, allowing one to sculpt the chromatic dispersion of the lens by adjusting the layered structure. Using Huygen's principle, we model our experimental measurements of the focal length of these lenses across the reflection band of the multilayer polymer film from which the microlens is fashioned. For a 56 μm diameter multilayered lens of focal length 300 μm, we measured a ∼ 25% variation in the focal length across a shallow, 50 nm-wide reflection band.
authors.forename: Michael
authors.initials: M
authors.lastname: Crescimanno
authors.forename: Tom N
authors.initials: TN
authors.lastname: Oder
authors.forename: James H
authors.initials: JH
authors.lastname: Andrews
authors.forename: Chuanhong
authors.initials: C
authors.lastname: Zhou
authors.forename: Joshua B
authors.initials: JB
authors.lastname: Petrus
authors.forename: Cory
authors.initials: C
authors.lastname: Merlo
authors.forename: Cameron
authors.initials: C
authors.lastname: Bagheri
authors.forename: Connor
authors.initials: C
authors.lastname: Hetzel
authors.forename: James
authors.initials: J
authors.lastname: Tancabel
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Singer
authors.forename: Eric
authors.initials: E
authors.lastname: Baer
mesh_terms: D007909:Lenses; D018625:Microscopy, Atomic Force; D055620:Optical Phenomena; D011108:Polymers / Q000737:chemistry*
chemical_list: D011108:Polymers