LCD与CRT电视显示器测试项目比较

介绍了LCD和CRT显示器的特性,对目前LCD和CRT电视显示器的测试项目如几何失真、可视角、亮度、对比度、响应时间等进行了比较.     

用LCD显示器测量人眼亮度对比度敏感视觉特性

根据LCD显示器亮度的均匀性和显示光栅对比度的稳定性实验分析,提出了一种采用LCD显示器显示光栅测量人眼对比度敏感视觉特性的实验方法,并测量了48位青年对象对3种平均亮度光栅的对比度视觉特性,且与目前有代表性的测量方法和结果进行了对比分析。结果表明该测量方法是一种有效、实用和简便易行的人眼对比度敏感视觉特性测量方法。     

软打样显示器的显色性能研究

显示器的显色性能会随着使用时间以及环境条件的改变而变化。本文以显示器显色性能为研究对象,设计一套系统的显示器性能测试实验,采用正交试验分析色温、亮度和Gamma值对EIZO CG247和Dell P2714H显示器显色能力的影响,为显示器确定合适的校准条件。此外,还对显示器的空间均匀性和时间稳定性进行了对比测试,以更好地将显示器应用于软打样。实验结果表明:对于两台显示器,在三个校准参数中,都表现为色温对显示器呈色的影响最大,Gamma值次之,亮度最小;两显示器的最佳显色参数都为色温6 500 K,亮度120cd/m~2,Gamma值2.2,但是Dell P2714H的平均色差1.06大于EIZO CG247显示器的0.64;并且两显示器在空间均匀性和时间稳定性方面表现相接近。     

应用于彩色FED显示器的亮度与灰度校正技术

为了改善彩色场致发射(FED)显示器的显示质量,分析了彩色FED显示器中存在的显示亮度不均匀、灰度损失和灰度畸变等问题.通过实验测试和理论分析,提出了相应的亮度与灰度的非线性校正方案.将该校正技术应用到彩色FED驱动电路中,使彩色FED图像的亮度均匀性和灰度再现性能得到了较好的改善,同时也增强了图像显示的层次和细节程度.     

TFT—LCD液晶显示器现状及发展

TFT-LCD显示器具有诸多优点:比普通CRT显示器能够节省大量空间;在重量、耗电等方面,LCD显示器的重量仅为同屏幕尺寸的CRT显示器的1/7左右,耗电量仅为CRT显示器的1/4;同时,LCD显示器有利于使用者的健康,可以说是一种真正意义上的无辐射产品;另外,由于不存在电子束的汇聚问题,LCD显示器不存在几何失真和散焦现象,新一代的LCD还具有不受电磁场的干扰、亮度较高、视角宽广的特点。     

LCD显示器阶调复现曲线的函数表达

通过对S-shape和S-curve函数曲线的分析,提出了LCD显示器阶调复现曲线的S-form函数表达.实验采用X-Rite Monitor Optimizer测量了两台LCD显示器和一台CRT显示器的阶调复现曲线,并分别用S-shape,S-curve和S-form函数进行了拟合,结果表明:S-form函数拟合阶调复现测量曲线优于S-shape和S-curve函数;S-form函数不仅适用于LCD显示器,也适用于CRT显示器.     

@OLED显示技术之三@

目前最流行的扁平显示技术是液晶显示器(LCD),这与它所具有的优点分不开,如其工作电压低、功耗小、毫无辐射、对人体健康无损害,完全平面、无闪烁、无失真、用眼不会疲劳,可视面积大,既薄又轻、能大量节省空间,其抗干扰也比CRT显示器强得多.因此,LCD在各种扁平显示领域中得到了较广泛的应用.但是,这并不表示它就是取代CRT显示器的最好代表,因为LCD显示器也有它不可克服的弱点,如视角小、亮度与对比度不够大,与CRT显示器相比,图像逼真度及饱和度仍不理想,响应时间也不够短等.虽然目前最新的TFT-LCD显示器已经对传统的LCD作了相当的改进,但是其昂贵的石英基板,不高的成品率使得液晶显示器的价格高高在上,同时也就限制了它的尺寸不能够做得太大,固而难以得到普及.     

LCD显示器与CRT显示器

LCD显示器与CRT显示器存在以下6个方面的不同。 厚度不同 CRT显示器由于采用真空显像管,因此厚度比LCD显示器大很多。 工作原理不同 CRT显示器的工作原理是在真空的显像管中,用电子束轰击显示屏而产生图像;而LCD液晶显示器,是使用液晶元件来调变光亮度而产生图像。     

三款15英寸液晶显示彩色电视机

虽然CRT(阴极射线显像管)彩色电视机性能不错、价格下降,目前仍然是家用电视机的主流机种,但许多公司新开发的LCD(液晶显示器)彩色电视机已开始在市场上亮相。二者相比,LCD彩电具有重量轻、占用空间小、屏幕绝对平坦、画面无弯曲畸变和闪烁等优点。此外,由于LCD显示器的屏幕没有掩蔽部分,比同一尺寸的CRT显示器具有更大的观看面积。所以,就画面大小而言,一台15英寸LCD电视机的实际观看效果相当于一台17英寸CRT电视机。目前LCD彩电的主要缺点是价格昂贵,图像的亮度和对比度还不如CRT彩电那样大,看起来比较乏味,但一些新型LCD彩电在这方面已有明显改进。因此,在选购LCD彩电时应注意检查其图像的亮度和对比度。如果只是用作彩色电视机而不打算用作PC显示器,则不必购买价格昂贵的高分辨率机型。下面介绍三款目前颇具代表性的15英寸LCD彩色电视机,看看它们有哪些特点。     

一种基于LCD-LED双调制显示器的HDR图像显示方法

提出一种针对HDR图像的显示方法,该方法应用于LCD-LED双调制高动态显示器,旨在使显示器更好地显示HDR图像要求的亮度细节,提高视觉质量。首先,建立HDR图像亮度与LED亮度范围对应关系,使用光扩散函数作为背光LED亮度取值范围的权重。然后,统计LED的亮度辐射区域内不同LED发光强度等级的权重,取权重最大者对应的亮度作为该背光LED亮度。最后,利用依据LED亮度生成LED背光扩散图像与HDR图像计算出LCD显示图像。仿真结果表明,该算法可以使显示器亮度失真率系数低至0.006以下。在LCD-LED双调制高动态显示器上实验验证结果表明,该算法可以有效提高图像的层次感,有效抑制LCD-LED双调制高动态显示器的"光晕"以及亮度截断现象,提高显示质量。     

LCDs versus CRTs-color-calibration and gamut considerations

This paper presents a comparative evaluation of liquid-crystal displays (LCDs) and cathode-ray tube (CRT) displays from a color-rendition and color-calibration perspective. Common display calibration models and assumptions are reviewed and their applicability to LCDs and CRTs is evaluated through an experimental study. The displays are compared with respect to the color-calibration accuracy, ease of calibration, and achievable color gamut. The offset, matrix, and tone-response correction model commonly employed for CRT color calibration is also suitable for color calibration of LCDs for most applications, though the calibration error for LCDs is higher For the prototype LCDs used in the experimental study, large color variations significantly above the calibration accuracy are observed with changes in viewing angle. Under typical viewing conditions, LCDs provide a significantly larger color gamut than CRTs primarily due to their higher luminances     

平面介质阻挡Xe放电荧光灯型LCD背光源的新进展

近年来随着大屏幕液晶显示器的快速发展，对背光源性能的要求也越来越高，使得各种新型背光源不断被开发出来。平面介质阻挡Xe放电荧光灯因其具有优越的光电特性，可望被用于台式电脑液晶显示器和液晶电视中。本文对具有代表性的几种新型平面介质阻挡Xe放电荧光灯进行了介绍，分析了进一步提高放电灯性能需要解决的问题。     

无阈值铁电液晶

简要介绍铁电、反铁电液晶的发现、发展、显示应用中遇到的问题以及近来发展起来的无阈值铁电液晶的研究结果,最后讨论无阈值铁电液晶应用前景。     

The flat panel's future

The development of active-matrix liquid crystal displays (AMLCDs) to overcome the limitations of passive LCDs is reviewed. The decision of video graphics adapter (VGA) versions of these displays, the market for these displays, and the companies involved in producing them are discussed. Two alternatives to AMLCDs, one involving a method for driving passive LCDs that would give them most of the benefits of active-matrix displays and the other involving standard passive-matrix color LCDs, are also discussed. The possibility of transferring LCD technology to the high-definition television (HDTV) market and the most likely candidate for that market, plasma display panels (PDPs), are examined     

The dawn of organic electronics

Organic semiconductors are poised to transform the world of circuit and display technology. Major electronics firms such as Philips and Pioneer, and smaller companies such as Cambridge Display Technology, Universal Display, and Uniax, are betting that the future holds tremendous opportunity for the low cost and sometimes surprisingly high performance offered by organic electronic and optoelectronic devices. Using organic light-emitting devices (OLEDs), organic full-color displays may eventually replace liquid-crystal displays (LCDs) for use with laptop and even desktop computers. Such displays can be deposited on flexible plastic foils, eliminating the fragile and heavy glass substrates used in LCDs, and can emit bright light without the pronounced directionality inherent in LCD viewing, all with efficiencies higher than can be obtained with incandescent light bulbs     

The World of Liquid-Crystal Display TVs—Past, Present, and Future

The full-fledge development for liquid-crystal display (LCD) technologies began aiming to achieve a ldquowall-mounting TVrdquo in the 1960 s. Since then, it has been more than 30 years from the birth of LCD product, the market of LCDs has grown above 10 billion dollars, and in the future, it is expected to further expand at a fast pace. The driving force in the current marketplace will be the original goal, ldquoLCD TVs,rdquo which contribute to drastically improving display performance of LCD and the evolution of LCDs. This paper, therefore, will focus on the LCD-TVs, and describe their history, the state-of-the-art of the technologies, as well as the prospect of their potential in the future.     

Assessment of Mobile Technologies for Displaying Medical Images

We compared the characteristics of state-of-the-art mobile display systems based on reflective and transmissive liquid crystal displays (LCDs) and an organic light-emitting display with respect to physical characterization metrics and observer studies. Physical performance factors provided information on the differences among display technologies. Observer studies resulted in different system ranking between the task-based performance and user-preference approaches. The results of the physical characterization and preference study showed that the reflective LCD ranked lower. We also found that ambient illumination played a lesser role than previously seen in large-format workstation displays. The methodology developed in this study provides an initial insight into the comparison of alternative technologies for display of diagnostic images in small portable devices.      

动作环境下液晶显示荧幕对阅读绩效与视觉疲劳之影响

今日交通工具中广泛使用液晶显示萤幕,荧幕也随着各式各样的振动对人产生影响.尤其人们眼睛在阅读精确的文章时,振动所造成不适,影响就变得更剧烈,因此容易造成阅读绩效不佳与视觉不适.本研究想要探讨液晶萤幕在不同振动情形(振动频率、振动振幅与不同振动方向)对数字大小、数字多寡与数字排列之影响.阅读绩效与视觉疲劳的量测为反应时间、正确率、闪光融合阈值、视力变化与主观评量,由实验得到频率对反应时间、正确率与视觉疲劳有显著的影响.因此荧幕硬件与软件之设计必须考虑到振动的影响.     

LCD背光源产品的新发展

目前，多数LCD器件都配备了背光源，在这些器件中，背光源对显示画面的亮度，对比度，发光均匀性等许多重要的性能都有影响，因而不断地改进LCD背光源，并研制新型LCD背光源是开发LCD技术的一个重要的组合部分。鉴此，对LCD背光源产品的新发展作了介绍。