A novel concept for protection of optical sensors will be described. The device consists of a transparent substrate, a transparent conducting electrode, insulating polymers, and a reflective top electrode layer. Using thin film deposition and photolithographic fabrication techniques commonly available for manufacture of integrated circuits, plus spin coatings as commonly used for polymers, the layers can be placed on the substrate and arrays of apertures created with sizes ranging from micrometers to millimeters. Due to the stress gradient between the polymer dielectric and the reflective metal electrodes, the composite thin film structure will open over the aperture area once a "release layer" is removed by chemical treatment. This is the "open" condition for the "eyelid". By applying a voltage between the transparent conducting and the metal electrodes, an electrostatic force is created which closes the "eyelid". Upon elimination of the voltage, the stress gradient opens the "eyelid" again. Preliminary devices have been fabricated and operated up to a frequency of 4 kHz and at lifetimes of over 1010 cycles. The power consumption is extremely low. The potential of this technoogy for a variety of applications will be discussed.
Revised: November 10, 2005 |
Published: June 15, 2000
Citation
Goodwin-Johansson S., P. Holloway, G. Mcguire, L.J. Buckley, R. Cozzens, R. Schwartz, and G.J. Exarhos. 2000.Artificial Eyelid for Protection of Optical Sensors. In Electroactive polymer actuators and devices, PROCEEDINGS- SPIE THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING, edited by Yoseph Bar-Cohen, 3987, 225-231. Bellingham, Washington:INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING.PNNL-SA-33320.