A Millimeter-Tunable-Range Microlens for Endoscopic Biomedical Imaging Applications

We report an electrothermally-actuated microlens scanner that is suitable for biomedical imaging applications. The microlens has a large tunable range and a low driving voltage, and the lens is made of glass. The enabling device is a new electrothermal actuator design that is capable of large vertical actuation (~0.9 mm) on a 3 mm device footprint, with small lateral shift (<; 7 μm) and tilting (<; 0.38°) at less than 4-V. The design, fabrication and characterization of the actuator are presented. Imaging results by the assembled microlens are also demonstrated.

[1]  D. M. Shotton,et al.  Confocal scanning optical microscopy and its applications for biological specimens , 1989 .

[2]  J. Izatt,et al.  Optical Coherence Tomography and Microscopy in Gastrointestinal Tissues , 1996, Advances in Optical Imaging and Photon Migration.

[3]  Gerhard Lammel,et al.  Optical Microscanners and Microspectrometers using Thermal Bimorph Actuators , 2002 .

[4]  V. Milanovic,et al.  Large-displacement vertical microlens scanner with low driving voltage , 2002, IEEE Photonics Technology Letters.

[5]  Luke P. Lee,et al.  Micromachined transmissive scanning confocal microscope. , 2004, Optics letters.

[6]  E. Cocker,et al.  Fiber-optic fluorescence imaging , 2005, Nature Methods.

[7]  Huikai Xie,et al.  An electrothermal SCS micromirror for large bidirectional 2D scanning , 2005, The 13th International Conference on Solid-State Sensors, Actuators and Microsystems, 2005. Digest of Technical Papers. TRANSDUCERS '05..

[8]  Markus F Neurath,et al.  Endoscopic confocal imaging. , 2005, Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association.

[9]  Huikai Xie,et al.  A thermal bimorph micromirror with large bi-directional and vertical actuation , 2005 .

[10]  Hans Zappe,et al.  Tunable microfluidic microlenses. , 2005, Applied optics.

[11]  W. Fang,et al.  Thermal Actuated Solid Tunable Lens , 2006, IEEE Photonics Technology Letters.

[12]  Hyun Joon Shin,et al.  Single fiber confocal microscope with a two-axis gimbaled MEMS scanner for cellular imaging. , 2006, Optics express.

[13]  W. Piyawattanametha,et al.  Two-Dimensional MEMS Scanner for Dual-Axes Confocal Microscopy , 2007, Journal of Microelectromechanical Systems.

[14]  Huikai Xie,et al.  124$^\circ$ Rotation Angle Electrothermal Micromirror With Integrated Platinum Heater , 2007, IEEE Journal of Selected Topics in Quantum Electronics.

[15]  A Lateral-shift-free LVD Microlens Scanner for Confocal Microscopy , 2007, 2007 IEEE/LEOS International Conference on Optical MEMS and Nanophotonics.

[16]  Huikai Xie,et al.  Microendoscopic Confocal Imaging Probe Based on an LVD Microlens Scanner , 2007, IEEE Journal of Selected Topics in Quantum Electronics.

[17]  L. Nieradko,et al.  On-Chip Scanning Confocal Microscope with 3D MEMS Scanner and VCSEL Feedback Detection , 2007, TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference.

[18]  Haishan Zeng,et al.  Magnetically actuated MEMS microlens scanner for in vivo medical imaging. , 2007, Optics express.

[19]  Hongrui Jiang,et al.  Tunable liquid microlens actuated by infrared light-responsive hydrogel , 2008 .

[20]  Huikai Xie,et al.  A large vertical displacement electrothermal bimorph microactuator with very small lateral shift , 2008 .

[21]  2D scanning MEMS stage integrated with microlens arrays for high-resolution beam steering , 2009 .

[22]  Caglar Ataman,et al.  2D scanning MEMS stage integrated with microlens arrays for high-resolution beam steering , 2009, 2009 IEEE/LEOS International Conference on Optical MEMS and Nanophotonics.