单玻璃基板与各向异性聚合物膜的IPS-LCD的应用

介绍了一种使用单片玻璃基板和各向异性聚合物膜的轻型、共面转换液晶显示(IPS-LCD)技术。液晶分子由伸长的聚合物膜内的颗粒排列。各向异性聚合物膜的取向性能与聚酰亚胺(PI)摩擦层相当。良好的液晶取向性能使新器件的对比度(514:1)、驱动电压和响应时间都能够与双玻璃基板LCD相比拟。这种各向异性膜也能作为拓宽视角的相位补偿膜来使用。该技术特别引人注目之处在于制作单基板显示器,同时它也具有实现双层宾主显示和IPS-LCD柔性显示的潜在应用。     

整合型液晶邦定机

用于液晶显示屏制作过程中的邦定技术目的是使TCP或FPC(柔性电路板)与ITO玻璃之间建立稳定连接的生产工艺,是液晶显示屏制作过程中的主要设备之一.介绍了针对液晶显示器制作工艺开发出的整合型邦定机,整合了各向异性导电膜(ACF)机构、预压对位机构、主压邦定机构.重点介绍了该设备的工作原理、系统控制设计、软件控制并指出了...     

An optically controlled liquid crystal device using azopolymerfilms

We have developed a liquid crystal (LC) device that is totally controlled using light. The initial alignment is made by optically buffing the azopolymer film with two coherent argon laser beams. Surface relief gratings have been optically induced on an assembled cell filled with LC. A single linearly polarized argon laser beam is then employed to irradiate the sample and photoinduce a twisted alignment structure. This can then be erased by a circularly polarized beam. The alignment information can also be erased by heating to the glass transition temperature of the azopolymer film     

Strong Vertical Alignment of Liquid Crystal on Porous Anodic Aluminum Oxide Film

Properties of anodic aluminum oxide (AAO) film as a liquid crystal (LC) alignment material is studied. We deposit the transparent porous AAO film on glass with the diameter of the pores controlled between 17–65 nm. The liquid crystal can be aligned vertically against the substrate with the AAO film. The measured polar anchoring strength is about 1.5 $,times 10 ^{-5} {rm J/m} ^{2}$, which is comparable to that of N,N-dimethyl-N-octadecyl-3-aminopropyl -trimethoxysilyl chloride (DMOAP) layer. AAO films with smaller pore diameters exhibit higher anchoring strengths. On the other hand, the uniformity of the pore array in the AAO films does not affect the alignment quality significantly.      

Anisotropic Change of Liquid‐Crystal Domains by Polarized Infrared Pulse Laser Irradiation for a Columnar Mesophase

The infrared photoinduced alignment change of liquid‐crystal domains was investigated for a hexagonal columnar mesophase of a liquid‐crystalline triphenylene derivative. A uniform and anisotropic alignment change of domains was observed when a polarized infrared (IR) light corresponding to the wavelength of the aromatic C–C stretching absorption band of the triphenylene core was used to irradiate the sample. The relationship between the aligned azimuthal angle of the columnar axis and the polarization of the IR incident irradiation was investigated. IR absorption dichroism is induced as a result of the reorientation of triphenylene core. Texture observation and polarizing microscope FTIR spectra show that a change of the molecular alignment occurred and that the direction of columns depends on the polarization angle of the IR light used for irradiation. The mechanism of the alignment change in a columnar liquid crystal film by IR irradiation is also discussed. The technique could provide a novel technology to control the columnar alignment of highly viscous liquid crystals.     

侧链密度对聚酰亚胺取向膜性能的影响

成功地合成了二胺单体十二烷氧基苯-4′,4″-二氨基三苯胺(DPDTA),并用此单体与3,3′-二甲基-4,4′-二氨基二苯甲烷(DMMDA)和二苯醚四羧酸二酐(ODPA)共缩聚,采用低温缩聚-热酰亚胺化、通过调节共聚物组成制备了2种聚酰亚胺(PI)。利用FT-IR、NMR、UV-Vis与DSC等手段对合成二胺单体及PI进行了结构表征和性能测试。研究了其取向性能、透光性能和耐热性能。结果表明,在摩擦前,含10%DPDTA的PI不能诱导液晶分子取向,含25%DPDTA的PI能诱导液晶分子垂直取向,预倾角可达89.6°。而摩擦后,两种PI都能使液晶分子平行取向,预倾角分别为1.8°和2.4°。两种PI膜在500～800nm区域透光率都在80%以上,玻璃化温度都在230℃以上。     

基于光敏自组装多层膜的液晶光控取向膜

采用layer-by-layer(LBL)的方法，将基板依次在具有光敏双键的季铵盐水溶液和聚乙烯基苯磺酸钠水溶液中浸泡，石英基板表面形成了自组装多层沉积膜。经线性偏振紫外光辐照后，LBL多层膜表现出明显的紫外吸收各向异性。将两片带有各向异性薄膜的基板做成平行液晶器件。在正交的偏光显微镜下观察，发现取得均一、稳定的取向效果。该种光控取向膜有望用作LCoS微显示的取向层。     

Optical scattering in a nematic liquid crystal induced by acoustic surface waves

A standing acoustic-wave pattern at 2.6 MHz is displayed in a nematic liquid-crystal film on a piezoelectric substrate. The striations are visible because the liquid crystal is optically anisotropic, because of the acoustically induced turbulence. This result has implications for liquid-crystal display systems.     

Wide-View MVA-LCDs With an Achromatic Dark State

A multi-domain vertical alignment liquid crystal display (MVA LCD) using a negative C-plate and a biaxial film is proposed to obtain an achromatic dark state. In comparison to conventional approach which uses a negative C-plate and a positive A-plate, the maximum light leakage over entire viewing cone is reduced by ~ 6X at lambda = 450 nm and ~ 4X at lambda = 650 nm. The achromatic dark state is essential for improving the contrast ratio, viewing angle and color saturation of MVA LCDs.     

一种新型液晶垂直取向膜

采用离子沉积法在玻璃基板表面制备了十四烷基磺酸盐自组装膜,用带有该自组装膜的基板制成的液晶器件呈现出垂直取向效果。通过自组装反应过程分析,认为自组装膜表面的纵向沟纹引起了液晶的垂直排列。实验发现,当自组装膜烷烃碳链长度大于11个C原子就可获得垂直取向。这种取向膜制作过程简单、热稳定性好,非常有望应用于多畴垂直取向模式的液晶显示器。     

一种采用内部线栅偏振片的半透半反射式液晶显示器

为了同时获得具有高透射率和反射率的液晶显示器,提出了一种采用内部线栅式偏振片(wiregridpolarizer,WGP)的单倍盒间距的半透半反式液晶显示器方法。在反射模式中,液晶盒内嵌的WGP作为依赖于偏振的外界光的反射器;在透射模式中,不需要消色差的四分之一波片。基于液晶盒的初始取向,该器件可用于正常显黑模式(垂直取向)和正常显白模式(扭曲向列相取向)。本文研究了这两种器件结构详细的电光特性,如电压依赖光效率特性和视角特性。     

A transflective liquid crystal display using an internal wire grid polarizer

To obtain high transmittance and reflectance simultaneously, a single cell gap transflective liquid crystal (LC) display using internal wire grid polarizer (WGP) is proposed. For the reflective mode, the imbedded WGP serves as a polarization-dependent reflector for the ambient light. For the transmissive mode, no achromatic quarter-wave film is needed. This device can be used as a normally black mode (using vertical alignment) and a normally white mode (using twist-nematic alignment), based on the initial LC cell alignment. Detailed electro-optic performance, such as voltage-dependent light efficiency and viewing angle of these two device configurations, is investigated.     

A new COG technique using low temperature solder bumps for LCD driver IC packaging applications

A new chip on glass (COG) technique using flip chip solder joining technology has been developed for excellent resolution and high quality liquid crystal display (LCD) panels. The flip chip solder joining technology has several advantages over the anisotropic conductive film (ACF) bonding technology: finer pitch capability, better electrical performance, and easier reworkability. Conventional solders such as eutectic Pb-Sn and Pb-5Sn require high temperature processing which can lead to degradation of the liquid crystal or the color filter in LCD modules. Thus it is desirable to develop a low temperature process below 160/spl deg/C using solders with low melting temperatures for this application. In our case, we used eutectic 58 wt%Bi-42 wt%Sn solder for this purpose. Using the eutectic Bi-Sn solder bumps of 50-80/spl mu/m pitch sizes, an ultrafine interconnection between the IC and glass substrate was successfully made at or below 160/spl deg/C. The average contact resistance of the Bi-Sn solder joints was 19m/spl Omega/ per bump, which is much lower than the contact resistance of conventional ACF bonding technologies. The contact resistance of the underfilled Bi-Sn solder joints did not change during a hot humidity test. We demonstrate that the COG technique using low temperature solder joints can be applied to advanced LCDs that lead to require excellent quality, high resolution, and low power consumption.     

聚合物分散液晶的应用

聚合物分散液晶是液晶分子以微滴的形式分散于高分子聚合物中,所形成的性能优异的一种液晶薄膜材料。文中介绍了PDLC的3大应用领域,在大屏弯曲显示方面具有传统液晶显示技术无可比拟的优势,是制作智能玻璃的核心材料,且可用于研制性能更好的可变光衰减器、波带片、透镜和调制器等重要光学器件,并指出纳米掺杂是改进PDLC性能的研究方向。聚合物分散液晶具有广阔的应用前景,且其生产工艺简单、成本低廉,应引起国内学者足够的重视,避免未来国外形成技术垄断。     

光敏自组装单层膜用于液晶光控取向的研究

用丁二酸酐和7-羟基香豆素合成了含有脂肪族羧酸基团的光敏化合物，利用脱水反应使它在玻璃(或石英)基板表面形成自组装单层膜。用偏振紫外光照射光敏性自组装膜，与光矢量方向匹配的香豆素基团发生[2 2]周环反应，反应产物沿辐照光的偏振方向分布，形成表面张力各向异性的薄膜。用它作为向列相液晶取向膜制成平行液晶器件，在偏光显微镜下观察，发现取得了均一、稳定的取向效果。并且该取向膜有良好的热稳定性。     

Understanding of Delamination Mechanism of Anisotropic Conductive Film (ACF) Bonding in Thin Liquid Crystal Display (LCD) Module

The chip-on-glass (COG) technique using anisotropic conductive film (ACF) has been developed for liquid crystal display (LCD) panels with excellent resolution and high quality for several years. However, many serious manufacturability and reliability issues were observed from previous studies. In those, delamination occurring at the ACF interface is one of the common concerns. Few works presented analysis of delamination mechanism through the whole COG bonding process with the combination of LCD module scale and ACF interconnect scale. In this paper, the delamination mechanism of COG/ACF interconnection was studied by using finite element analysis. Equivalent block and global-local modeling methods were implemented with nonlinear elastic-plastic and sequential coupled thermal-mechanical analysis. The critical parameters of the COG bonding process and geometry of integrated circuit (IC) and glass were investigated to understand the mechanism of ACF delamination. It was found that the delamination could be reduced by decreasing the temperature difference between bonding head and glass substrate or using thin and short IC. The local model analysis revealed that the interface of glass/ACF epoxy encountered the higher stress than that in the interface of IC/ACF epoxy and had the higher possibility to delaminate. Therefore, increasing the bonding-strength between glass and ACF epoxy is the direction to reduce the probability of ACF delamination.     

微波退火非晶硅薄膜低温晶化研究

多晶硅薄膜晶体管以及其独特的优点在液晶显示领域中起着重要的作用。为了满足在普通玻璃衬底上制备多晶硅薄膜晶体管有源矩阵液晶显示器,低温制备（＜600℃高质量多晶硅薄膜已成为研究热点。文章研究了一种低温制备多晶硅薄膜的新工艺;微波退火非晶硅薄膜固相晶化法,利用X射线衍射、拉曼光谱和扫描电镜分析了微波退火工艺对非晶硅薄膜固相晶化的影响,成功实现了低温制备多晶硅薄膜。     

TFT-LCD残像原理与分析-加强篇二

残像是TFT-LCD的一种显示特性,主要表现为当液晶显示器长时间显示同一个画面,在把画面切换到下一个画面时,原先的画面会残留在下一个画面中。本文的加强篇二从材料面的彩膜、液晶、配向膜及工艺面的配向膜工程、ODF工程导致的残像具体分析了其原因和改善方法。     

一种新型TFT-LCD用配向膜材料研究

基于面内转换IPS(In-Plane-Switching)液晶显示模式采用新型的光配向技术,相比摩擦配向技术具有无静电、无污染、可控的预倾角等优势。但同时存在显示画质不良如残像,对产品良率及客户体验感影响很大。本文通过对三款聚酰亚胺材料制备及应用光配向技术形成取向层,首先对聚酰亚胺材料特性进行研究,分别为亚胺化率、接触角、Edge Margin、表面各向异性;再对画质不良残像原理进行简单分析,根据残像画面呈现形式分为长期残像与短期残像。通过一系列测试结果得出最优材料亚胺化率为92%、Edge Margin为70.6nm、接触角为78.5°、表面各向异性光配向能量为300mJ,能够满足目前生产要求;实验测试显示画面为短期残像LV2水平优于量产LV3水平,低电阻率(1×10~(12))配向膜对残像具有明显改善效果,能够很好满足客户需求。同时本文研究思路对后续新材料测试及验证具有一定的参考价值。     

未经摩擦处理的可聚合液晶制备的延迟膜

研制了一种由可聚合液晶制备的延迟膜。这种延迟膜是一种负性C-plate,利用胆甾相液晶的性质,对于采用垂直取向(verticalalignment,VA)模式的液晶盒进行光学延迟补偿。所述延迟膜使用不经摩擦处理的取向层,制备工艺简单,且具有优良的光学性能。