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The energy consumption of buildings is influenced by the climates tremendously. Taiwan is an island covered with high mountains. Crossed by the tropic of cancer, the basic climates zones include tropical and subtropical climates. In this research, the degree day and degree hour methods were used to analyze 37 weather stations data in mid and high elevation regions of Taiwan collected over 10 years. The WRF model were used to predict summer cooling hours using 26, 28, 30°C as the base temperatures. The research showed that Taiwan has complicated climate zones due to the variations of the elevation. The low air-conditioning load areas in the mid and high elevation regions will be the most suitable areas to design low energy consumption buildings in Taiwan.

Environmental conditions for the roughly three million people living in the Taipei basin of Taiwan are greatly affected by the land–sea breeze and afternoon thunderstorm activities. A new perspective on the land–sea breeze life cycle and how it is affected by afternoon thunderstorm activity in the Taipei basin during the dry season is provided. During the summer monsoon break–revival phase, about 75% of rainfall in the Taipei basin is produced by afternoon thunderstorms triggered by sea-breeze interactions with the mountains to the south of this basin. Because the basic characteristics of the land–sea breeze and the changes it undergoes through the influence of afternoon thunderstorms have not been comprehensively analyzed/documented, a mini–field experiment was conducted during the summers of 2004 and 2005 to explore these aspects of the land–sea breeze in this basin. Thunderstorm rainfall is found to change not only the basin’s land–sea-breeze life cycle, but also its ventilation mechanism. On the nonthunderstorm day, the sea breeze supplies the open-sea fresh air for about 8 h during the daytime, but the land breeze persists on the thunderstorm day from afternoon to the next morning, acting to sweep polluted urban air out of the basin.

Outdoor thermal environments influence thermal adaptation, thereby affecting the utilization of space. To determine the effects of thermal comfort and adaptation on attendance regarding different shading levels and activity types, this study conducted field investigations at a public park located in southern Taiwan, using micrometeorological measurements, estimations of park attendance, and questionnaire surveys on thermal comfort. The results indicate that participants' acceptable range of thermal comfort leads to substantial changes in overall park attendance during different seasons, whereas characteristics of thermal adaptations influence the individual differences of utilization in various ways within diverse spaces. In addition, this study reveals that in unshaded areas within parks, the number of visitors increases following rising thermal conditions during cool seasons, whereas the number of visitors decreases during hot seasons. However, the number of visitors to shaded areas increases with rising thermal conditions in both cool and hot seasons. Because of the possibility and effectiveness of personal behavior adjustments (e.g., decreases in the amount of clothing worn, the wearing of hats, or carrying of an umbrella) in decreasing thermal discomfort, people choose to seek adjustments in external environments. That is, they move from unshaded to shaded areas to relieve their perception of thermal discomfort. The results of this study reveal the importance of shading facilities within parks in the hot climate zone of Taiwan, and can be used as references in future park designs.

In order to decrease the impacts of climate changes and global warming on the environment, many countries have started the zero carbon or low carbon researches to decrease the production of CO2. The government of Taiwan also follows the trend in conserving energy and decreasing carbon production and develops a “low carbon island” demonstration plan. The energy consumption of a building is closely linked to the climates of its location. Therefore, studying the local climates is the foundation of low carbon building design. However, the meteorological data collected for general purposes do not provide detailed sorting and time selection for building design. Therefore, it is important to create an architectural meteorological database specially for building design. In this research, we created an architectural meteorological database for Liuqiu island, an off-shore island in the “low carbon island” plan of Taiwan. Using this database, the building designer can improve the natural ventilation design of the building to decrease the usage of air conditioning and the goal of low carbon building can be achieved easily.

In order to accommodate the global climate change, the idea of constructing zero-carbon green buildings has become the main stream and highest standard in building design in many countries. Located in subtropical zone, Taiwan features hot and humid weather in summer. The high usage of air conditioning is the main challenge to design zero-carbon green buildings in Taiwan. However, the temperature in the middle and high mountain areas decreases as altitude increases and makes it possible to create a living environment without using air conditioning in the summer. This project analyzed weather data in the middle and high mountain areas of Taiwan. The degree hour method and weather research and forecast model were used to evaluate the demand of air conditioning in the summer based on outside air temperature. The results showed that the low air conditioning load areas are above 1000 m elevation. This project then simulated energy consumption of a two-floor building near the Sun Moon Lake, an area of low air conditioning load, to explore the feasibility of zero-carbon green buildings in Taiwan. Based on the life style of a four-member family, a simulation process was conducted to estimate energy consumption of various appliances and different life habits. This study showed that the energy consumption in the buildings can be reduced up to 70% by using three major design strategies. These strategies include selection of a low air conditioning load location, using high energy efficient appliances, and application of energy conserving habits. Followed by renewable energy evaluation, it is possible to put zero-carbon green building into practice in Taiwan.

Solar radiation data is an important consideration factor in building environment planning. This study focused on the regional characteristics of global solar radiation of Taiwan. The research utilized the raw meteorological data meseaursed by the Central Weather Bureau to establish reliable solar radiation data of weather stations by means of statistic analysis. A total of weather station’s data are used where their geographical location are evenly distributed from northern to southern Taiwan. The results of this study will presented the diagrams of annual and monthly averaged solar radiation in Taiwan. Geographical distribution of inter-annual trend of global solar radiation during this period was also presented in this paper. It can be used for further study of the climate zoning comparing with other climate conditions. Furthermore, researchers of solar cell design, building energy, shading design, site planning, etc. can utilize the distribution diagram to fetch reliable solar radiation values to carry on reasonable quantitative analysis.

This study employs simulated electronic paper to investigate critical issues and focuses on improving legibility of display and reducing users' visual fatigue. Three critical factors--choice of surface treatment, ambient illumination, and bending curvature--are evaluated through the method of a letter-search task. The results show that subjects performed better on legibility and felt less visual fatigue with an anti-glare treatment. Choosing the better anti-glare treatment instead of the anti-reflection series can save significant cost for manufacturers. In addition, ambient lighting of 1500 lux is more appropriate for reading on electronic paper than an environment with extreme illumination (e.g., 8000 lux). The present study also found that curvature had no impact on legibility or visual fatigue. These evaluations of simulated electronic paper may provide manufacturers useful information in fulfilling ergonomic requirements for product design.

This study examined the effects of anti-glare surface treatment, ambient illumination and bending curvature on legibility and visual fatigue in reading electronic papers. Results showed that surface treatment significantly affected legibility and visual fatigue, and surface treatment can improve legibility and reduce visual fatigue under intense ambient illumination. However, there is no significant difference on bending curvature. In addition, due to no significant difference between anti-glare 43% haze and anti-glare 7.5% haze, it is suggested that electronic paper manufacturers may use cheaper options for cost consideration.

A plasma-beam-irradiated PI film has been used in flexible liquid crystal display manufacturing. The beam had energy of 450 eV and incident angle of 70° with respect to normal flexible indium-zinc-oxide coated substrate. The pretilt angle and anchoring energy of LCs on plasma aligned PI surface were almost identical to those on rubbing aligned PI surface. However, the optical performance of plasma aligned cell was superior to the rubbing cell under various bending conditions. Furthermore, such non-contact alignment technology is suitable for large area and roll-to-roll fabrication of flexible LC films.

Conjugated poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) films, prepared by inkjet-printing and spin-coating methods, have been studied using atomic force microscopy, micro-Raman spectroscopy, photoelectron spectroscopy, and four-point probe conductivity measurements. Electrical conductivity of the inkjet-printed film was enhanced by a factor of around 10 when compared to a spin-coating film. The improved conductivity was attributed to longer effective conjugation length of PEDOT chains in inkjet-printing PEDOT:PSS films as suggested by their micro-Raman spectroscopy. PEDOT:PSS films formed by the inkjet-printing method are appropriate for use as an anode for simplification of the fabrication process of polymer light-emitting diodes whose performance is about 1.2 cd/A.

A numerical study of a cold surge that occurred from 19–23 December 2001 was conducted to better understand the cold surge characteristics over the Taiwan area. The National Centers for Environmental Prediction (NCEP) nested Mesoscale Spectral Model (MSM) was used for this study. Simulation results demonstrated that the nested NCEP MSM captured salient features of the selected cold surge case. We demonstrated that the local minimum center of the time change of virtual potential temperature (dVPT) can serve as the location of severe weather of the cold surge for all Taiwan regions. Furthermore, thermodynamic equation analyses revealed that the leading edge of the cold surge was maintained primarily by meridian thermal advection, while diabatic heating, vertical and zonal thermal advections were less important.

This paper describes a recording of a holographic grating on a homeotropically aligned dye-doped liquid crystal (DDLC) cell. The photo-excited azo dyes, methyl red (MR), diffuse and adsorb onto the substrates, thereby forming a ripple structure. The adsorbed dye and the laser-induced ripple structure then reorientate the liquid crystal molecules, and induce a holographic grating.

This study reports the observation of two-beam coupling (2BC) in polymer-dispersed liquid crystal (PDLC) films during the formation of a holographic grating. A non-stationary grating effect causes such a coupling. Based on the model we propose for the dynamic behavior of a PDLC grating, the experimental results agree well with the 2BC theory.

Influences of anti-reflection and anti-glare surface treatments, radius of curvature and ambient illuminance on legibility and visual fatigue of reflective-type displays were studied. The results showed that legibility and visual fatigue mainly depended on the surface treatment, and better surface treatment can improve legibility and reduce visual fatigue especially in the intense ambient illumination. Surface treatments of 0.8% anti-reflection and 44% anti-glare show the same visual performance.

The finite-difference time-domain (FDTD) method is a powerful numerical algorithm used to directly solve Maxwell's equations. We introduce the idea of the FDTD method and the techniques required for optical simulation of cholesteric liquid crystal (Ch-LC) devices. Bragg reflection characteristics of Ch-LC cells are investigated using the FDTD method. Three approaches to broadening the bandwidth of Bragg reflection are demonstrated: (1) using a higher birefringence LC, (2) using a cell with a gradient pitch length, and (3) using a cell with a new multidimensional structure of a Ch-LC.

The nanoparticles-induced vertical alignment (NIVA) of the nematic liquid crystals (LC) was proposed to make a tunable liquid-crystal flat microlens with hybrid-aligned nematic (HAN) mode, which was fabricated using micro drop technology. The minute amount of nanoparticle solution was dropped on the selective area, which was surrounded by homogeneous alignment layer. Due to vertical alignment induced by the nanoparticles, the liquid-crystal concave microlens with concentric non-uniform distribution of the refractive index was then formed in the planar LC cell. The divergence effect of this flat lens was observed and its focal length can be electrically controlled at applied voltages.

The technique, nanoparticles-induced vertical alignment (NIVA), was applied to fabricate a guest-host liquid crystal display (GH-LCD) without conventional alignment layers. The GH-LCD produced by NIVA exhibited a high reflectance of approximately 59% in the voltage-off state and a low threshold voltage of approximately 2.1 V(rms). NIVA is very suitable to be applied for fabricating a plastic LCD requiring a low temperature process, and a flexible timepiece by using NIVA was demonstrated.

A polarizer-free flexible and reflective electro-optical switch using dye-doped liquid crystal (LC) gels is demonstrated. The electro-optical performances of both scattering and absorption based dye-doped LC gels depend on curing temperatures due to domain sizes of polymer networks. Such flexible electro-optical switch is bendable and trim-able because of the vertical polymer networks and gel-like materials. The dye-doped LC gel shows good reflectance ~55%, good contrast ratio~450:1 and fast response~6.4 ms at curing temperature 10 degrees C. The bending curvature is 21 mm. The dye-doped LC gels open a new window for trim-able electronic papers, decorative displays, electrically switchable curtains, and electrically switchable sun control film for the automobiles, homes or commercial buildings.

A flexible and reflective polarizer-free display using dye-doped liquid crystal (LC) gels is demonstrated. The electro-optical performances of both scattering and absorption based dye-doped LC gels depend on curing temperatures. The dye-doped LC gel shows good reflectance ~55%, good contrast ratio~450:1 and fast response~6.5ms at curing temperature 10 °C when UV curing intensity is 2.6 mW/cm2. The EO performance depends on the curing temperature. The hysteresis is independent of sampling time duration. The bending curvature is 21 mm. The response of dye-doped LC gels is faster under bending due to the bending-induced sheared force of polymer networks. The dye-doped LC gels open a new window for trimable electronic papers, decorative displays and switchable curtains.

We describe a fast optical recording material based on a dye-doped polymer-dispersed liquid-crystal film. A holographic grating is written in this film with a single Q -switched Nd:YAG laser pulse that has a duration of ~6 ns . Such a grating is due to the reorientation effect of the liquid-crystal molecules through interaction with the photoinduced adsorption of the doped azo dyes. Experimental results indicate that the grating thus formed is permanent but electrically switchable.

A reflective polarizer-free liquid crystal display (LCD) using dye-doped LC gels is demonstrated. The main mechanism is to combine dye absorption and polydomain scattering. The potential applications are electronic papers and flexible displays.

The following report presents innovative technique for surface modification and device construction of top-contact pentacene-based thin film transistors (TFTs) with saturation mobility about 2.0 cm 2 /Vs. In the experiment we have utilized PSPI as a modification layer presenting a non-polar interface on which the semiconductor, pentacene, could grow. The surface of the modification layers was exposed to a polarized ultraviolet light with dose ranging from 0.2 J to 8 J. Ultraviolet light was applied to achieve a non-polar surface on which high performance TFTs have been subsequently fabricated. The experimental results showed that the parasitic contact resistances of silver electrodes could be extracted by gated-transfer length method, and the corrected field-effect mobility of pentacene TFTs for linear region was as high as 2.25 cm 2 /Vs. In this study, we were able to control the surface energy of polymer-based gate dielectric layers and the surface energy of the PSPI layer increasing the energy from about 38 to 42 mJ/m 2 by differentiating doses of polarized ultraviolet light. When the PSPI film was exposed to 1 J of polarized ultraviolet light, the surface energy of PSPI, measured by the contact angle method, was about 38 mJ/m 2 . The measured energy matched the theoretically calculated surface energy of a pentacene crystal. Hence, the higher mobility OTFTs with low surface energy gate dielectric were obtained by spin-coating the PSPI as a modifier.

We first demonstrated that an organic electroluminescence (EL) device based on conjugated polymers, which emitted polarized light, aligned by ion beam processed films of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). Such devices would be particularly useful as backlights for conventional LCDs. Homogenous alignment of 4,4'-Bis[2-9(-ethyl-3-carbazoyl)vinylenyl]-1,1'-biphenyl (BECVB) films on thin layers of ion-beam-processed or rubbed PEDOT:PSS allows the construction of light-emitting diodes that emit polarized blue light (λ em = 455 nm). The ion-beam-processed or rubbed PEDOT:PSS acts as an effective hole-injecting alignment layer. Polarized photoluminescence spectra demonstrated that the long axis of BECVB molecule was oriented along the ion-beam or rubbing direction. Owing to the orientation of BECVB molecules, polarized EL in the rubbing or ion-beam direction was observed in the device. The maximum photoluminescence polarization ratios of 5.6:1 and 3.2:1 were achieved for the devices aligned by rubbing and ion-beam methods, respectively.

A paper-like cholesteric liquid crystal (ChLC) display has been developed by photo-induced polymer/ liquid crystal phase separation process. Depending on this process, the homogeneous mixture of ChLC and pre-polymer would separate into polymer walls and ChLC rich region. Polymer walls formed by photopolymerization of pre-polymer provide several advantages of flexible display applications such as good mechanical properties and low cell gap tolerance. The ChLC rich region was a composite combined by the ChLC and dispersed polymer. This dispersed polymer was derived from the residue polymer in the display area after the phase separation process. This dispersed polymer was used to disturb the alignment of ChLC, and break the planar structure into multi-domain planar structure which would present the white appearance in the planar state. The electro-optical properties were measured by Otsuka LCD 5100 and Eldim EZ Contrast 160RH. The relationship between phase separation process and electro-optical properties was also been developed.

A novel hybrid LCD technology has been developed. By replacing a glass color filter with a plastic color filter, a lighter and thinner hybrid LCD can be obtained. A 4" QVGA prototype has been demonstrated. A hybrid LCD can reduce 35% thickness and 36% weight compared with a conventional LCD with 2 glass substrates. This technology can be a good solution for portable display.

200 /spl mu/m thickness of film-like display was developed and a contrast ratio of 35 with a driving voltage of 20 V was observed. In addition, organic TFT is used to drive LCD display. 0.05 cm/sup 2//Vs of electron mobility and 10/sup 5/ of current on/off ratio are achieved.

A single cell-gap transflective color TFT-LCD has been fabricated by a novel double gamma method where two TFTs were used to control the reflective region and transmissive region independently. This novel design can simplify the manufacture process and improve the image performance compared with other transflective displays.

A microstructure replication technique to make a high contrast micro-cell LCD has been developed. The robust microstructure can sustain the cell gap very well. Compared with the traditional photopolymerisation-induced phase separation, the micro-cell LCD has higher contrast ratio and more reliable manufacturing process. This technique could be applied in the high performance and low cost flexible LCDs.

This study first demonstrated the feasibility of using the photoalignment method to adequately control the structural anisotropy of pentacene films, which are active semiconducting layers, in thin-film transistors (TFTs) with conspicuous anisotropic electrical characteristics. The photoaligned pentacene films were characterized with respect to structure and morphology using x-ray diffraction, atomic force microscopy and Raman scattering. Compared to the uncontrolled pentacene films, a maximum 25-times increase in field-effect mobility (up to 0.82 cm 2 /Vs) is achieved in the photoaligned pentacene-based TFTs by aligning pentacene orientation parallel to the current flow direction using a photoaligned polyimide layer. Mobility anisotropic ratios ranging between 2.7 -8.3 for the current flow parallel and perpendicular to the alignment of the photoaligned pentacene films have been observed for photoaligned pentacene-based TFTs.

This article describes light-induced reorientation effects on a homeotropical dye-doped liquid crystal (DDLC) cell. The photo-excited azo dye, methyl red (MR), diffuses and adsorbs onto the substrate, thus forming a ripple structure. The adsorbed dye and laser-induced ripple structure then reorient the liquid crystal molecules and induce a holographic grating. Initially, the LC directors are reoriented primarily by the adsorbed dye. However, given sufficiently large ripple groove amplitude, the torque imposed by the ripple grooves overcomes that owing to the adsorbed dyes, and the LCs are realigned along the groove direction.

The effects of light-induced reorientation on a homeotropical dye-doped liquid crystal (DDLC) cell are discussed. The photoexcited azo dye Methyl Red (MR) is diffused and adsorbed onto the substrate, thus forming a ripple structure. The adsorbed dye and the laser-induced ripple structure then reorient the liquid-crystal molecules and induce a holographic grating. Initially, the liquid-crystal directors are reoriented primarily by the adsorbed dye. However, given a sufficiently large ripple groove amplitude, the torque imposed by the ripple grooves overcomes that which is due to the adsorbed dyes, and the liquid crystals are realigned along the groove direction.

A UV-cured adhesive with a low glass transition temperature (Tg) below the room temperature was used as a substrate for manufacturing a film-like liquid crystal display. This film-like liquid crystal display shows a fully flexibility due to the low Tg property, and the manufacture processes are roll-to-roll compatible due to the coating processes.

A multi-switch display using gradient dye-doped LC gels which is still polarizer-free, fast response (∼10ms in general), and high contrast (∼200:1 in general) has demonstrated. By controlling the spatial distribution of the density of polymer networks through fabrication process, gradient dye-doped LC gels can be a multi-switch. The gradient dye-doped LC gel is bright without applied voltage and is dark at a high voltage. It appears the colored pattern when LCs are partially reoriented due to the gradient density of polymer networks. The optical analysis of dye-doped LC gels is also discussed. The potential applications are flexible display and decorative displays.

We have found that nanoparticles of polyhedral oligomeric silsesquioxane (POSS) can induce vertical alignment in nematic liquid crystal (LC) cells as long as the doped weight percentage of POSS in the LC cells is higher than ~1%. Such nanoparticle-induced vertical alignment (NIVA) is a very suitable technique for application in the low-temperature fabrication of plastic LC displays. The dynamic process of LC orientation from randomly parallel alignment to vertical alignment was recorded, and it is posited that the POSS NIVA is due to the adsorption of POSS on the inner surfaces of the LC cells. The influence of the POSS concentration on the electro-optical properties and dielectric constant of LC cells was also investigated and the results indicate that LC cells doped with ~1 wt% POSS provide the best electro-optical performance.

A polarizer-free flexible display using a dye-doped nematic liquid crystal (LC) gel is demonstrated in reflective mode and transmissive mode. By mimicking the display principle of a paper, combing both scattering and absorption, such a bendable and trim-able LCD exhibits∼55% reflectance, ∼450:1 contrast ratio in reflective mode, ∼20:1 contrast ratio in transmisive mode, and 15 ms response time. A single pixel flexible reflective display using such dye-doped LC gels is also demonstrated under bending and cutting. The minimal bending radius of curvature is ∼21mm.

The spontaneous vertical alignment of the mixtures consisting of nematic liquid crystals (LCs) and nanoparticles and its application to hybrid-aligned nematic (HAN) modes were investigated. The LC directors were aligned perpendicular to the nontreated indium-tin-oxide surface by adding the nanoparticles. Therefore, we fabricated a nanoparticle-filled HAN LC cell without using the vertical alignment layer. The electro-optical properties of nanoparticle-filled HAN cells are very similar to those of conventional HAN cells containing vertical alignment layers. The method of nanoparticle-induced vertical alignment is suitable for fabricating a flexible display due to the reduction of high temperature process of alignment layers.

This letter reports that adding nanoparticles in the negative dielectric anisotropic liquid crystal (LC) cell can exhibit the properties of vertical alignment without using alignment layers. The electro-optical properties of this nanoparticles-induced vertical alignment in the LC cell are very similar to the conventional homeotropic LC cell with alignment layers. This technique can be used to fabricate a flexible LC display requiring a low temperature process.

˙The perturbation in the National Centers for Environmental Prediction (NCEP) Regional Spectral Model (RSM) is defined by the difference between the RSM and its outer model, such as the NCEP global model, on the same given coordinate surfaces. This perturbation is dominated by the difference between terrains of the RSM and the global model if model terrain exists over the domain. After being transformed into spectral space, this difference in terrains is characterized by two distinct groups of coefficients i.e., long-wave and short-wave groups. The long-wave group is considerably larger in amplitude than the short-wave group, and considered to be the cause of error in horizontal diffusion of perturbations on sigma surfaces. A higher order of diffusion and diffusion without long waves on sigma surfaces with perturbations are formulated to investigate the possibility of using diffusion on sigma surfaces. In a typical case, erroneous circulation occurred when fourth-order diffusion on a sigma surface was used; however, reasonable circulation was simulated with second-order diffusion on the pressure surface. Nevertheless, diffusion on a pressure surface is a non-economical method in spectral modeling. The results of sixth- and eighth-order horizontal diffusions of perturbations and no-diffusion on the group of long waves for all orders (second, fourth, sixth, and eighth) on sigma surfaces did not show errone

Liquid crystals (LCs) in flexible cell were aligned on polyimide (PI) surface treated by a paperlike plasma beam. The beam had energy of 450 eV and incident angle of 70° with respect to normal flexible indium-zinc oxide-coated substrate. The pretilt angle and anchoring energy of LCs on plasma-aligned PI surface were almost identical to the angle and energy of the rubbing PI. However, optical performance of the plasma-aligned cell was superior to the rubbing cell under various bending conditions. Furthermore, such noncontact alignment technology is suitable for large area and roll-to-roll fabrication of flexible LC films.

An innovative technique for surface modification of pentacene thin-film transistors (TFTs) with mobility greater than 1.92 cm2 V-1 s-1 is reported in this paper. Photosensitive polyimide was used as a modification layer presenting a nonpolar interface on which the semiconductor, pentacene, could grow. The surface of the modification layer was exposed to a polarized ultraviolet light with a dose of 1 J to achieve a nonpolar surface on which high-performance TFTs have been fabricated. The experiment showed that the parasitic contact resistances of silver electrodes could be extracted by the gated-transfer length method, and the corrected field-effect mobility of pentacene TFTs in the linear region was as high as 2.25 cm2 V-1 s-1.

We have successfully fabricated high-contrast microcell liquid crystal displays (LCDs) using microstructure replication technology in thin plastic film substrates. These novel flexible LCDs comprise microcell replication, alignment treatments, and cell assembly. The cell gap of such flexible LCDs was maintained well by cross-type spacers formed by photolithography, despite bending: moreover, the deviation in cell gap under various bending states was less than 0.1 µm. The structure, fabrication technique, and basic display characteristics of the flexible LCD are also described. Finally, this device shows high mechanical stability against external bending, a high contrast ratio of 500:1, and an acceptable response time. Compared with photopolymerisation-induced phase separation, the micro-cell LCD has a higher contrast ratio, a more reliable fabrication process, and a strong potential as a high-performance flexible LCD.

The surface free energy of a dielectric has a strong influence on the performance of pentacene thin-film transistors. Research shows that by matching surface free energy in the interface of the dielectric and the orthorhombic thin-film phase of pentacene film, the field-effect mobility of transistors is enhanced reaching above 2.0cm2∕Vs. The authors suggested that a more complete first monolayer of pentacene was formed upon the gate dielectric surface with almost identical surface free energy, benefiting carrier transportation. The research also discusses the mechanism of surface free energy effects on the crystalline size and structural disorder in pentacene film.

The following research describes the process of fabrication of pentacene films with submicron thickness, deposited by thermal evaporation in high vacuum. The films were fabricated with the aforementioned conditions and their characteristics were analyzed using x-ray diffraction, scanning electron microscopy, polarized Raman spectroscopy, and photoluminescence. Organic thin-film transistors (OTFTs) were fabricated on an indium tin oxide coated glass substrate, using an active layer of ordered pentacene molecules, which were grown at room temperature. Pentacene film was aligned using the ion-beam aligned method, which is typically employed to align liquid crystals. Electrical measurements taken on a thin-film transistor indicated an increase in the saturation current by a factor of 15. Pentacene-based OTFTs with argon ion-beam-processed gate dielectric layers of silicon dioxide, in which the direction of the ion beam was perpendicular to the current flow, exhibited a mobility that was up to an order of magn...

Effects of character size under ambient illuminance and light source on legibility of electronic papers were studied. Legibility was evaluated by a letter-search task. The results showed that search speed increased with illuminance level and character size. However, the effect of illuminance and light source on search accuracy was not statistically significant.

The finite-difference time-domain (FDTD) method is applied to investigate the Bragg reflection of cholesteric liquid crystal (CLC) devices, and a multi-dimensional structure of CLC for achieving broadband Bragg reflection and wide viewing angle is introduced.

Pentacene films with submicron thickness, deposited by molecular beam deposition, were fabricated and characterized using X-ray diffraction, atomic force microscopy, and Raman spectroscopy. Organic thin-film transistors (OTFTs) were fabricated on a p-type silicon substrate, using an active layer of highly ordered small pentacene molecules grown at room temperature. Pentacene film was aligned using the photoaligned polyimide method, which is usually employed to align liquid crystals. Improved field-effect mobility, in the range 0.40.75 cm 2 /V‚s, was obtained in pentacene-based OTFTs with photoaligned polyimide layers in which the pentacene molecules were aligned parallel to the direction of the transport of the carriers. The mobility was improved when the current flowed parallel or perpendicular to the orientation of the pentacene films with anisotropic ratios of 2.7-8.3. The thin-film structures of pentacene on the photoaligned polyimide surface depend on the dose of UV light that irradiates on the polyimide surface. X-ray analyses reveal that the structure of the highly ordered pentacene films includes only a single “thin-film phase”, generated by optimizing the energy of irradiation of the photoaligned polyimide. However, the poorly aligned films include two phases: a “single-crystal phase” and a “thin-film phase”.

Liquid crystals in our experiments could be aligned on a SiO2 surface bombarded by a neutral argon ion beam of an appropriate energy. Also, the pretilt angle of liquid crystals could be varied between 0 and 3.5°, by controlling the argon ion beam with an energy of 500 eV at an incident angle varying from 0 to 85° that was measured from the normal of the substrate. Finally, the twist nematic test cell of the 6 µm cell gap incorporating SiO2 alignment films exhibited a high optical transmission and a fast response time when the angle of the incident ion beam was more than 45°.

We have developed two kinds of ultra-flexible film-like liquid crystal display, pixel-isolated twist nematic and polymer encapsulated liquid crystal displays. By the aids of polymer wall in the thin display, the variation of the cell gap in the bending condition is greatly reduced. They are good candidates for the rollable flexible display due to the excellent flexibility. In this work, this is the first time that the electro-optical properties and reliability of a film-like liquid crystal display after bending test are investigated, and the application limit is investigated.