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We numerically calculate dynamical behaviors of the molecular reorientation of liquid crystal (LC) directors and of the phase retardation in an LC optical device with eight-divided circularly hole-patterned electrode and external transparent electrode. The three-dimensional (3D) distributions of the elliptical phase retardation in the hole-patterned aperture can be obtained by adjusting the applied voltage to each electrode. The transient properties of the phase profile can be estimated and be predicted fairly well by the numerical calculation. [ABSTRACT FROM AUTHOR]

Abstract: A stacked structure of liquid-crystal (LC) layers is proposed to build an LC lens of fast operation and large lens power. An LC lens of two LC layers is realized experimentally. By using the thin LC layers, the response time is controlled around 1s. A new drive method, which can prevent the occurring of disclination lines in the LC layers, is discussed in details. [Copyright &y& Elsevier]

Liquid crystal lenses(LCL)of two liquid crystal(LC)layers with parallel and orthogonal optic axes are built. The LCL of two LC layers with parallel optic axes is designed to obtain larger focusing power, and that with orthogonal optic axes is to focus light wave of arbitrary polarizations. The focal lengths of both LCLs can be controlled by external voltages. [ABSTRACT FROM AUTHOR]

The primary objective of this study is to design a cylindrical liquid crystal lens with ideal phase profile, which also overcomes the associated drawbacks of current cylindrical liquid crystal lenses, such as high driving voltages, numerous voltage sources, and complex manufacturing processes. By designing the shape of the indium tin oxide electrode, the parabolic distribution of the resistance is realized, thereby forming a parabolic voltage distribution. The driving voltages are controlled within the voltage range that the phase of liquid crystal layer responds linearly to voltage, so a parabolic phase profile is obtained. The designed indium tin oxide electrode is developed by photolithography. The phase profiles are extracted from interference fringes obtained by use of polarization interferometry. The phase profile maintains parabolic during focus tuning, a positive-negative tunable cylindrical liquid crystal lens with near-ideal phase profile is demonstrated experimentally. The full width at half maximum of normalized intensity at focal plane is smaller than the corresponding diameters of Airy disks, which means the positive lens has a good focusing effect. The negative lens expands the beam to about twice its original width, it is in accordance with the principles of geometrical optics. • Nearly ideal phase profile in the whole focus range (inherent parabolic phase profiles). • The focal length is positive-negative tunable, thus doubling the possible optical power. • Linear relation between the optical power and the driving voltages. • More flexible in design because the voltage profile is produced by the circuit unit outside the lens area. • Easy for mass production. [ABSTRACT FROM AUTHOR]

An imaging system is designed with a liquid crystal (LC) lens as the focusing element. The aperture of the LC lens plays the role of the aperture stop of the system. An entrance pupil larger than the LC lens aperture is realized and the magnification of the image formed by the system remains unchanged when the focal length of the LC lens is changed by the applied voltages. [ABSTRACT FROM AUTHOR]

We propose a laser manipulator for controlling positions and rotation of trapped microscopic particles suspended in water by using a liquid crystal (LC) device. This LC device has unique functions such as an anamorphic lens property, variable-focusing and deflection properties. The trapped slender particle can be aligned along the major axis of the elliptically shaped laser beam spot and the position of the particle can be controlled. Furthermore, the positions of multiple microscopic particles can also be controlled along the interference fringe patterns of a wedge LC cell. [ABSTRACT FROM AUTHOR]

A new method of voltage application is proposed to increase the focus range of a liquid crystal lens driven by two voltages. It is possible for the optical power of the liquid crystal lens to change in a wider range, while the root mean square aberration of low level is maintained. The liquid crystal lens is driven by a frequency of the voltages different in positive and negative lens states to obtain its largest optical power in each state. An obvious increase in focus range is realised. [ABSTRACT FROM AUTHOR]

Transient properties of a liquid crystal (LC) lens are investigated. It is shown that the LC lens maintains its lens properties as it is driven to switch between positive and negative lens states. Its optical power changes from positive to negative values and rms aberration also changes with time but always keeps below 0.1 wavelength. This transient property of the LC lens is made use of to acquire image of extended depth of field. [ABSTRACT FROM AUTHOR]

We use a liquid crystal (LC) lens to create a foveated imaging system which contains a camera module as a main lens, an LC lens as a foveated device, and an image sensor. The principle and experimental results are given. The influences on imaging of the parameters, including the position and aperture of the LC lens, and the aperture of the lens module, etc, are discussed. [ABSTRACT FROM AUTHOR]