Abstract

The liquid crystal adaptive lens (LCAL) is an electrooptic device that emulates a variable focal length lens. The LCAL focuses light by creating a parabolic refractive-index profile across the aperture of a liquid crystal cell. The focal length is electronically controlled by applying appropriate voltages to the array of independent electrodes, thus grading the refractive index of the liquid crystal material across the aperture. Beam translation perpendicular to the optical beam path is described theoretically and demonstrated. This capability coupled with the LCAL’s programmable focal length allows 3-D beam control. Meshing, the smoothing of the refractive index between adjacent electrodes, is a critical parameter in achieving near diffraction-limited optical performance. Using two planar electrodes and a ground plane immersed in an isotropic dielectric as a model, a steady-state dc theoretical computer simulation is compared with experiment. Improvements in the liquid crystal cell design demonstrate improved performance over previous LCALs. A larger number of electrodes creates an image without spatial aliasing within the aperture.

© 1988 Optical Society of America

Imaging performance of the liquid-crystal-adaptive lens with conductive ladder meshing

Wing W. Chan and Stephen T. Kowel
Appl. Opt. 36(34) 8958-8969 (1997)

Focusing by electrical modulation of refraction in a liquid crystal cell

Stephen T. Kowel, Dennis S. Cleverly, and Philipp G. Kornreich
Appl. Opt. 23(2) 278-289 (1984)

Adaptive spherical lens

Stephen T. Kowel, Philipp Kornreich, and Akbar Nouhi
Appl. Opt. 23(16) 2774-2777 (1984)

Polarization independent blue-phase liquid crystal cylindrical lens with a resistive film

Yan Li, Yifan Liu, Qing Li, and Shin-Tson Wu
Appl. Opt. 51(14) 2568-2572 (2012)

Adaptive dielectric liquid lens

Hongwen Ren, Haiqing Xianyu, Su Xu, and Shin-Tson Wu
Opt. Express 16(19) 14954-14960 (2008)