Chao-Chiun Liang

Critical Field for a Hysteresis-Free BPLC Device

A correlation between the peak electric field and hysteresis of a polymer-stabilized blue-phase liquid crystal (BPLC) is found experimentally. If the peak electric field is below ~ 5 V/μm, hysteresis is negligible. Based on this guideline, we propose elliptical protrusion electrodes to reduce peak electric field which in turn eliminates hysteresis while keeping a high transmittance. Such a hysteresis-free BPLC device is highly desirable for display and photonic applications.

71‐1: Development of Micro‐Pixellated GaN LED Array Micro‐Display System

This paper developed a micro-pixellated GaN LED (μ-LED) array micro-display system. The μ-LED array has the features of high luminance, small optical machine size, high collimation, and lost cost. A time-separate driving method is proposed to drive the micro-display system for releasing the LED over-current and efficiency thermal degradation issues.

A rugged display: Recent results of flexible cholesteric liquid-crystal displays

— A 3-m-long rugged flexible display having a novel single-plastic-substrate structure has been demonstrated with a coated cholesteric liquid-crystal mixture. The display is designed to be fabricated by a roll-to-roll process to increase productivity at a competitive cost. It has the advantage of having almost no limitation in display length. The high-resolution (300-dpi) monochrome cholesteric liquid-crystal display (ChLCD) can be achieved by using a photo-addressing method. A single-layered 10.4-in. color ChLCD also has been developed with good color and contrast.

Accurate-gray-level and quick-response driving methods for high-performance electrowetting displays

Abstract— To achieve quick-response electrowetting displays (EWDs) with accurate multiple-gray-level performance for video applications, several phenomena, such as hysteresis, charge trapping, and oil splitting, need to be addressed. This paper proposes a driving scheme that includes the decoupling driving concept, the asymmetric driving concept, the charge-trapping-suppression method, and the oil-splitting method. The proposed driving scheme was extensively investigated on a developed evaluation platform, and satisfactory results for multiple-gray levels and quick response were obtained for a 6-in. SVGA EWD.

7.4: A Stacking Color Electrowetting Display for the Smart Window Application

The electrowetting display with the property of transflective is applicable as windows. However, low transmittance is a key issue of a stacking color electrowetting display as a window application. To improve the transmittance, an advanced oil splitting suppression waveform was proposed. Finally, a stacking color electrowetting display for the smart window application has been demonstrated. And the transmittance up to 30% has been attended.

27.3: A Decoupling Driving Scheme for Low Voltage Stress in Driving a Large-Area High-Resolution Electrowetting Display

To reduce voltage stress on TFT backplane of electrowetting displays, this paper develops a decoupling driving scheme to diminish the induced voltage stress and allow AC common to reduce the required output voltage from driver IC. Satisfactory results can be obtained on a largest area and highest resolution electrowetting display.

30.3: Master Parameter Governing the Response Time of Reflective Cholesteric Liquid Crystal Displays

We investigated theoretically and experimentally the response time of cholesteric liquid crystal displays (ChLCDs). It turned out that the response time depended more on the structural change of twisted layers of ChLCs than the speed of the individual reorientation of LC directors. Numerical calculations showed that the surface anchoring energy of the substrates governed the transition from the homeotropic to the planar texture: ChLCs anchored weakly (Ws ≤ 10−5J/m2) on the bounding substrates undergo homogeneous transition, which is fast, while ChLCs anchored strongly (Ws ≥ 10−3J/m2) undergo defect-assisted heterogeneous transition, which is slow. Experimental results agreed well with the theoretical results.

30.1: A New Drive Scheme for Cholesteric Reflective Displays Under Active Matrix Addressing

A novel drive scheme for reflective cholesteric active matrix displays is proposed. This method is composed of two stages, a fast resetting phase which drives the cholesteric to the homeotropic state and a determining phase where different voltages are applied in order to get different gray levels of reflectance. When the determining voltage is low, a bright high reflective planar state is achieved while when the voltage is high, a dark focal conic state is formed. We experimentally demonstrated that the drive scheme works well for video ratio operation.

56.3: A Charge Trapping Suppression Method for Quick Response Electrowetting Displays

To achieve quick response electrowetting displays for video applications, the charge trapping phenomenon should be well coped with. for this purpose, an asymmetrical driving concept is proposed and a charge-trapping suppression method is developed in this paper. The performance of the proposed method was investigated and satisfactory results were obtained.

P‐141: Real‐Time Dynamic Characteristics Measurement and Automatic Driving Parameters Extraction for Dynamic Driving Bistable Cholesteric LCD

To obtain the dynamic driving parameters for cholesteric LCD in a systematic manner, its dynamic characteristics and then driving parameters should be measured and extracted respectively. Accordingly, this paper develops a real-time dynamic characteristics measurement system and an automatic dynamic driving parameters extraction scheme. Satisfactory results can be obtained experimentally.