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We synthesize three liquid crystal molecules with angular anthradithiophene (a-ADT) as the core for the application in organic film-effect transistors (OFETs). Thiophene-octyl group and thiophene-dodecyl group are introduced on both sides of the a-ADT core to yield compounds Bis-C8T-a-ADT and Bis-C12T-a-ADT. Moreover, thiophene-dodecyl group is attached to the a-ADT core on one side to yield compound C12T-a-ADT. The synthesized compounds are measured by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) to determine their mesomorphic properties. Compound Bis-C8T-a-ADT shows nematic and smectic A phases while both compounds Bis-C12T-a-ADT and C12T-a-ADT reveal smectic A phases. The optical and electrochemical properties of the compounds are characterized by UV–vis spectroscopy and cyclic voltammetry (CV). The HOMO levels for Bis-C8T-a-ADT and Bis-C12T-a-ADT are estimated to be −5.27 eV while the HOMO level of C12T-a-ADT is estimated to be −5.34 eV. The low-lying HOMO levels of the molecules indicate their great oxidation stability in OFET devices. The carrier mobilities are observed to increase 10–1000 times using rubbed polyimide (PI), resulting from the better arrangements of the liquid crystal molecules, and excellent carrier mobilities of 1.06 and 1.02 cm2/Vs are obtained from compounds Bis-C12T-a-ADT and C12T-a-ADT, respectively.

A thieno [3,2-b] thiophene-based planar liquid crystal molecule, C12-PTTT, which possesses the characteristics of an organic field-effect transistor (OFET), was synthesised and its mesomorphic properties were studied by polarising optical microscopy and differential scanning calorimetry. A wide temperature range for a highly oriented smectic phase was observed. OFET devices made under various conditions, such as self-assembled monolayer treatment and alignment treatment, and with micro-channel structures, were fabricated to measure the electrical properties. Among different OFET device conditions, the best electric carrier mobility for C12-PTTT was 0.038 cm2 V−1 s−1.

Color sequential transmissive and reflective projection displays using a vertical field switching (VFS) polymer-stabilized blue phase liquid crystal (BPLC) are proposed. The VFS-BPLC exhibits submillisecond response time which is useful for suppressing color breakup, hysteresis-free for accurate grayscale control, high optical efficiency, and low operation voltage.

The unplugged electronic display were fabricated and investigated in this study. The electro phoretic display (EPD) and solar cell device were laminated as an ultra thin structure, leading to a flexible, light and unbroken characteristics. Also, surface engineering for dust-proof and water-proof was performed for product application. Furthermore, the electricity generated by solar cells can support the operation of EPD device by maximum power point tracking (MPPT) technology.

We investigated the electrooptical properties of vertically aligned ferroelectric liquid crystal (VAFLC) cells by applying a transverse electric field induced by interdigital electrodes. Compared with a surface-stabilized FLC (SSFLC) cell, a VAFLC cell has an analog-grey scale capability requiring a high driving voltage. In this study, we propose two alignment methods, the single- and double-sided rubbed methods, to reduce the driving voltage of the VAFLC cell. The dynamic response time is below 1 ms in our methods. A single-sided polyimide aligned method can achieve a contrast ratio of 520 at an applied voltage of 50 V.

The synthesis of two series of liquid crystalline polyoxiranes and polyoxetanes containing 4-(4-hydroxybiphenyl-4′-carbonyloxy)- phenyl (2S,3S)-2-chloro-3-methylvalerate side groups is presented. Differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction measurements reveal liquid crystalline phases for all obtained polymers. A majority of the prepared polyoxiranes present cholesteric, smectic A, chiral smectic C and an undefined smectic phases. Most of the prepared polyoxetanes reveal only a chiral smectic C phase. Effect of polymer backbone and spacer length on the mesomorphic properties of the obtained polymers is discussed. Although the polyoxirane and polyoxetane backbone are more flexible than the polymethacrylate backbone, side-chain crystalization does not occur in any of the synthesized polymers.

A 6-inch rollable active-matrix electrophoretic display driven by organic thin-film transistor is demonstrated by using solution and photolithography processes. All process temperature are kept below 120 degree C. Pixel OTFT devices exhibit an average mobility of 0.6 cm2/Vs and good reliability. The rollable EPD prototype has thin (125um) and light (14g) features. The minimum rolling diameter can reach 25 mm.

This study investigates the effects of ambient atmosphere on electrical characteristics of Al2O3 passivated InGaZnO thin film transistors during positive bias temperature stress. Under H2O vapor environment, the Al2O3 passivated device exhibited stable electrical behaviors (ΔV th < 0.5 V), while the unpassivated device showed an apparent hump effect in the transfer curves under bias stress. The hump phenomenon was attributed to the absorption of the H2O molecule which can serve as a donor to develop a conductive back channel. The experiment results suggest that Al2O3 is an effective passivation layer to suppress water vapor absorption in the InGaZnO back channel.

With the technology of display getting mature, the desire of the stereo vision on display is in great demand. Many vivid 3D display technologies can be found in different application market, including shutter glasses, pattern retarder, lens-type… etc. However, there is no perfect 3D display technology so far. Besides, there is still room for the content to improve and need to be studied how to fit in related 3D display technologies. The key to link the software (3D content) and hardware (display) is human factor. In this talk, we share the 3D technology development experience and some human factors study, which will show the importance of the content flexibility.

An advanced MVA technology, AMVA III (AUO or Advanced MVA generation III) which is a protrusion-free technology has been developed. The AMVA III TFT-LCD panel has high optical transmittance (20% higher than conventional MVA), high static contrast ratio (>8000:1), fast response time, low color washout, and substantially free from motion blur. This advanced technology is newly launched for mass-production in LCD-TV.

In this paper we succeeded to develop a approach by using new material, named gray bump in stead of current bump material to achieve excellent contrast ratio(CR) of liquid crystal display(LCD) at normal direction for MVA mode. Meanwhile, we needn't change any processes, and surely no additional cost. Except CR enhancement at normal direction, it can also reduce the oblique light leakage of dark state and improve the viewing angle. We evaluate the response time and reliability for image sticking of this new bump design and it has the similar response time and image sticking performance as the original bump design. Finally, we also show the CR >3000:1 32″ TV that adopting this new design and using higher CR polarizers with lower haze value surface treatment.

We report an advanced gamma control technology for color wash-out free liquid crystal display (LCD) with individual subpixel control technique. The measured Δu'v' of the skin color is less than 0.02 at whole viewing angle. Compared to the conventional gamma setting, this advanced technology provides not only lower color wash-out but the smoother oblique gamma curve with the suitable area ratio design. This implies that the delicate display quality can be achieved without artificial contour in oblique view.