Biologically Inspired Artificial Compound Eyes and Optofluidic Systems

Luke P. Lee* Department of Bioengineering, University of California at Berkeley, USA

Abstract

In this talk, biologically inspired optofluidic systems and artificial compound eyes will be presented. Compound eyes in nature present intriguing topics in physiological optics due to their unique optical scheme for imaging. For example, a bee's eye has thousands of integrated optical units called ommatidia spherically arranged along a curvilinear surface so that each unit points in a different direction. The omni-directionally arranged ommatidium collects incident light with a narrow range of angular acceptance and independently contributes to the capability of wide field-of-view (FOV) detection. Artificial implementation of compound eyes has attracted a great deal of research interest because the wide FOV exhibits a huge potential for medical, industrial, and military applications. So far, imaging with a FOV over 90° has been achieved only with fisheye lenses which rely on bulky and expensive multiple lenses and require stringent alignment. However, we have recently accomplished the artificial ommatidium, like that of insect’s compound eyes, consists of a refractive polymer microlens, a light-guiding and self-aligned polymer cone and waveguide to collect light with a small angular acceptance. The ommatidia are omni-directionally arranged along a hemispherical polymer dome such that they provide a wide field-of-view similar to a natural compound eye. After accomplishing deformed elastomer membrane with microlens patterns for the creation of more than 8,700 microlens array on 3D dorm shaped single lens, biomimetic self-assembly of waveguides by self-aligned with microlenses are realized by a self-writing process in photopolymers. The angular acceptance is directly measured by three-dimensional optical sectioning with a confocal microscope and the detailed optical characteristics are studied in comparison with a natural compound eye. If time permits integrated tunable optofluidic system on microfluidic network for dynamic imaging systems and adaptive optics and a tunable microdoublet lens capable of creating dual modes of biconvex or meniscus lens for minimizing optical aberrations and maximizing the tunability of focal length or field of view by controlling variable and fixed lens curvatures will be also discussed.

*Current address: Center for Biosystems Science and Engineering, ETH Zurich-Basel, Switzerland

Prof. Luke P. Lee is Lloyd Distinguished Professor of Bioengineering at UC Berkeley. He is also Director of Biomolecular Nanotechnology Center and Co-Director of Berkeley Sensor & Actuator Center. He received both his B.A. in Biophysics and Ph.D. in Applied Science & Technology (major: Applied Physics & minor: Bioengineering) from UC Berkeley. Prof. Lee has more than ten years of industrial experience in integrated optoelectronics and Superconducting Quantum Interference Devices (SQUIDs). His current research interests are single cell biophysics, quantitative systems biology, molecular diagnostics, soft-state biological devices, and biologically inspired Biomedical-Polymer-Opto-Electro-Mechanical-Systems (BioPOEMS), and Biomolecular-Polymer-Opto-Electronic Technology and Science (BioPOETS). Prof. Lee has authored and co-authored over 150 journal and proceeding articles on BioMEMS, BioPOEMS, SQUIDs, nanostructured SERS, and nanogap dielectric biosensor for label-free biomolecule detection.