Focus-Tunable Microlens Arrays Fabricated on Spherical Surfaces

Author

Zhu, Difeng ; Zeng, Xuefeng ; Li, Chenhui ; Jiang, Hongrui

Author_Institution

Dept. of Electr. & Comput. Eng., Univ. of Wisconsin, Madison, WI, USA

Volume

20

Issue

2

fYear

2011

fDate

4/1/2011 12:00:00 AM

Firstpage

389

Lastpage

395

Abstract

We present microlens arrays consisting of multiple focus-tunable microlenses omnidirectionally fabricated on spherical surfaces, to realize large field of view. Thin flexible polymer bridges connecting adjacent microlenses are designed to reduce the wrapping stress and deformation of the microlens array. Each microlens, formed via water-oil interface, is individually tuned by a thermo-responsive hydrogel actuator. The range of the focal length of each microlens in this array varied from millimeters to infinity. A prototype of optical imaging system based on such a microlens array on a spherical surface, including a charged-coupled device camera, a fiber bundle, and a 3-D rotational stage, is demonstrated as well.

Keywords

CCD image sensors; actuators; deformation; microlenses; optical arrays; optical design techniques; optical fabrication; optical fibres; optical focusing; optical images; optical polymers; optical tuning; 3D rotational stage; charged-coupled camera device; deformation; fiber bundle; focal length; focus-tunable microlens arrays; omnidirectional fabrication; optical imaging system; spherical surfaces; thermoresponsive hydrogel actuator; thin flexible polymer; water-oil interface; wrapping stress; Apertures; Bridges; Fabrication; Lenses; Microoptics; Polymers; Stress; Curvilinear surface; field of view (FOV); focus tunable; microlens array;

fLanguage

English

Journal_Title

Microelectromechanical Systems, Journal of

Publisher

ieee

ISSN

1057-7157

Type

jour

DOI

10.1109/JMEMS.2011.2105858

Filename

5709962