Liquid Crystal And Polymer Composite Film Research Articles

An optical image stabilisation using a droplet manipulation on a liquid crystal and polymer composite film

ABSTRACTWe demonstrate an image system with an optical image stabilisation using a droplet manipulation on a liquid crystal (LC) and polymer composite film (LCPCF) to reduce motion blur while preserve image quality. Such an image system adopts a liquid lens on an LCPCF and the mechanism is on a basis of droplet movement on LCPCF whose position changes because electrically tunable orientations of LC molecules on the surface of LCPCF. The change of position of the liquid lens compensates the deviation of light as the image system is under a handshake vibration. As a result, the image system under handshake vibrations could keep a clear image. The operating principles are introduced, and the experiments are performed and discussed. The concept in this paper can also be extended to design other optical components for modulating direction of light.

A droplet manipulation on a liquid crystal and polymer composite film as a concentrator and a sun tracker for a concentrating photovoltaic system

We demonstrate a droplet manipulation on a liquid crystal and polymer composite film (LCPCF) as a concentrator and a sun tracker for a concentrating photovoltaic (CPV) system with a steady output electric power. The CPV system adopts a liquid lens on LCPCF whose curvature is not only tunable but position is also bistably switchable based on liquid crystal orientations on LCPCF. The change of curvature of the liquid lens results in a tunable concentration ratio which helps to increase photocurrent at a low illumination and prevent the effect of the series resistance at a high illumination. Moreover, the change of the position of the liquid lens helps to track sun owing to sun movement. Therefore, the output power of such a system is steady no matter the sunlight condition and the angle of incident light. The operating principles and experiments are investigated. The concept in this paper can be extended to design optical components for obtaining steady output power of the solar cell at indoor or outdoor use and also tracking sunlight.

A Sperm Testing Device on a Liquid Crystal and Polymer Composite Film

Developing a handy sperm testing device is important since sperm quality is a significant factor for fertility potential. In this paper, we demonstrate a sperm testing device based on a switchable surface, a liquid crystal and polymer composite film (LCPCF). The wettability of LCPCF is electrically switchable due to the electrically tunable orientations of liquid crystal molecules. In experiments, two motions of a semen drop on switchable surface of LCPCF are observed: back-and-forth stretches and collapses of semen drops. The better quality spermatozoa results in back-and-forth stretches of a semen drop on LCPCF; otherwise, the semen drop collapses. The motility and concentration of semen can also be sensed by the stretch distance and collapse distance of semen drops, respectively. The mechanism of back-and-forth stretches of semen drops results from fertile sperms swimming against the flow with the periodic changes of the orientation of LC molecules with pulsed voltages. The mechanism of collapses of semen drops results from the washed-away infertile sperms which are deposited on LCPCF and then re-modify surface of LCPCF. Potential applications for this device include sperm testers and microfluidic devices for Assisted Reproductive Technology.

An electrically switchable surface free energy on a liquid crystal and polymer composite film

An electrically switchable surface free energy on a liquid crystal and polymer composite film (LCPCF) resulting from the orientations of liquid crystal molecules is investigated. By modification of Cassie’s model and the measurement based on the Chibowski’s film pressure model (E. Chibowski, Adv. Colloid Interface Sci. 103, 149 (2003)), the surface free energy of LCPCF is electrically switchable from 36×10−3J/m2 to 51×10−3J/m2 while the average tilt angle of LC molecules changes from 0° to 32° with the applied pulsed voltage. The switchable surface free energy of LCPCF can help us to design biosensors and photonics devices, such as electro-optical switches, blood sensors, and sperm testers.

AN ELECTRICALLY TUNABLE FOCUSING PICO PROJECTION SYSTEM BASED ON A LIQUID CRYSTAL LENS ADOPTING A LIQUID CRYSTAL AND POLYMER COMPOSITE FILM

An electrically tunable liquid-crystal-on-silicon (LCOS)-based pico projection system based on a liquid crystal lens adopting a liquid crystal and polymer composite film (LCPCF) is demonstrated. The LC lens consists of two built-in sub-lenses: one is an electrically tunable focusing lens controlled by a LC layer and the other is a fixed focused LCPCF lens. The electrically tunable focusing range of the pico projection system is 200 cm to ~7 cm when the voltage is from 0 to 35 Vrms. The image performance is also demonstrated. The related optical analysis is discussed. This study opens a new window for electrically tunable focusing pico projection system.

P‐144: A Reflective Polarizer‐free, Color‐filter‐free, and Bistable Display Using a Droplet Manipulation on a Liquid Crystal and Polymer Composite Film

AbstractA single pixel of a polarizer‐free, color‐filter‐free, and bistable display using a droplet manipulation on a liquid crystal and polymer composite film (LCPCF) is demonstrated. Because of the electrically tunable orientation of the liquid crystal directors anchored among the polymer grains, the wettability of the LCPCF changes with an applied electric field. As a result, we can manipulate a color droplet on LCPCF by distribution of LC directors on LCPCF and then realize a reflective polarizer‐free bistable display. The contrast ratio is around 8:1 in a reflective mode.

A bistable polarizer-free electro-optical switch using a droplet manipulation on a liquid crystal and polymer composite film

A bistable, polarizer-free, and reflective electro-optical switch based on a droplet manipulation on a liquid crystal and polymer composite film (LCPCF) is demonstrated. A color droplet on LCPCF can be manipulated by a wettability gradient owning to the distribution of LC directors anchored among the polymer grains on LCPCF. The contrast ratio is around 8:1 in a reflective mode. The potential applications of droplet manipulation are electronic papers and reflective displays.