Dein SHAW and S. P. CUO^*

Department of Power Mechanical Engineering, National Tsing Hua University, 101 Kung Fu Rd. Sec. 2, Hsinchu, Taiwan 30013, R.O.C.

(Received August 24, 2010; Accepted September 30, 2010)

The purpose of this study is to find the best shapes of a flexible image sensor of a hemispherical electronic eye to fit with the Petzval surface of a variable focus lens. The flexible image sensor which can obtain a clearer and wider image compared with that attained by an electronic eye with a flat image sensor. In this study, the sensor chips are on a flexible membrane, and that membrane is deformed by applying a hydraulic pressure load. The deformed shape of the membrane for different pressure and different material properties are fit with the Petzval surface to find which conditions of the membrane have the best fit. It is found that the deformation shapes of membranes of Young's modulus 0.75 and 1.5 MPa, thickness 0.3 mm, and diameter 20 to 25 mm are fit for Petzval surfaces of different focal lengths from 15 to 40 mm.

Key words: variable focus, liquid filled lens, electronic eye, flexible image sensor, Petzval surface

^*E-mail address: d9633833@oz.nthu.edu.tw