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排序方式: 共有342条查询结果,搜索用时 15 毫秒
181.
Chang‐Jae Yu Cherlhyun Jeong Sin‐Doo Lee 《Journal of the Society for Information Display》2006,14(6):537-543
Abstract— Three nonchiral‐smectic‐C (NSC) liquid‐crystal (LC) modes having fast‐response and wide‐viewing characteristics applicable for next‐generation LCDs are described. In the NSC LC modes, fast analog optical modulation is achieved by means of a coupling with an external electric field in a dielectrically driving scheme. The fast response results intrinsically from no interlayer interferences during molecular rotation in the layered structure of the NSC LC. Moreover, the self‐formation of two domains and the in‐plane variations of the optic axis produce the wide‐viewing properties. A step‐wise temperature annealing process is employed for a stable and well‐aligned smectic layer structure in a time‐efficient manner. 相似文献
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183.
View selection aims at finding good views that can watch model information as much as possible. However, existing view evaluation methods used to measure model properties are generally complex and very time‐consuming. In this paper, we address this challenge by generating succinct proxy information to measure the view quality. The proxy information is generated by principal component analysis of the model to obtain its six principal viewing directions and consists of the representative information computed by the principal viewing directions. We discuss and validate the effectiveness of the proxy information for view evaluation. Thus, measuring the proxy information for view evaluation, the time complexity can be reduced as it is independent of the facet number of the model. This is superior to existing methods by straight measurement of model properties and provides acceleration for view selection. Experimental results show that we can obtain good views as state‐of‐the‐art methods and speed up view selection by at least two orders of magnitudes and achieve more acceleration when the models have more facets. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
184.
叙述了看图思维必备的基础知识和记忆点线面投影特性的技巧 ,介绍了看图思维的基本方法及看图步骤 ,对看图思维的基本规律进行了归纳和分析 相似文献
185.
一种新的二步周视彩虹全息术 总被引:2,自引:0,他引:2
在二步周视彩虹全息图制作光路中布置一块大孔径的菲涅耳螺纹透镜及预置狭缝,既可获得具有较大观察口径的周视彩虹全息图,又可大幅度提高记录时光能的利用率。文中给出了理论分析与实验结果。 相似文献
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The dynamic qualities of looking around and moving about, directly sensing spatial queues, using one’s peripheral vision, and focusing with foveal vision on objects of attention are fundamental to a person’s visual experience in landscape. Unfortunately, the visual media commonly used to structure scientific analysis, professional design, decision-making and artistic interpretation of visual landscapes are quite weak at portraying the dynamic and peripheral dimensions of human vision. Also, visual media whether it be manual drawing, photomontage or state-of-the-art computer animation tend to be time consuming and difficult to apply to these dimensions of seeing. The absence of a convenient, cost-effective means for showing all the fundamental visual aspects of landscape in a balanced way is a serious limitation.This deficiency begs the following questions. Is the current state of knowledge in visual landscape management biased by the relative ease with which established media, such as illustration, photography, and photo-realistic rendering can be used? Do the characteristics of these media bias our perception and thinking about landscape toward static foveal aspects of visual experience? Are our ideas about dynamic viewing and computer animation limited by the didactic frame-by-frame approach characteristic of cinematography and video? Can the introduction of equally robust tools and methods for dynamic and peripheral viewing balance any bias caused by current visualization technology?If McLuhan’s insights about media are correct, then we need to do more research on this question. This paper suggests that the field of landscape visualization needs to develop instruments for research that more fully capture the fundamental components of human vision before we can properly study the question or advance practice. It outlines some ways the next generation of visualization technology can be used to balance the disproportionate emphasis on foveal ways of visual thinking commonly used in the past for the study of visual landscapes. The paper explains this deficiency and proposes some area for research and development of visualization instruments more capable of redressing this imbalance.The paper outlines this issue and proposes that as electronic media and computational media become more developed and are applied to the realm of visual concerns, it will become more practical to include peripheral vision and dynamic viewing in deliberations about visual landscapes. This paper reflects on the potential of visualization automation techniques to overcome these shortcomings through illustrations of project work using innovative software tools developed to explore this question at the Centre for Landscape Research (CLR) at the University of Toronto. 相似文献
188.
针对在未知环境中的地图建立和定位,提出了一套具体的方法和步骤。通过对激光数据进行处理,采用viewing sector的方法实现局部地图与全局地图的融合。将生成局部地图的激光数据点与全局地图的进行匹配,并生成误差函数,使用F-R共轭梯度法对其进行极小化,实现对机器人的定位。仿真表明,该算法可以在建立地图与定位时,保证良好的精确性。 相似文献
189.
在垂面排列液晶显示模式中,液晶分子垂直取向,具有暗态良好、高对比度的特点,但是其视角特性不佳。采用MVA和PVA技术等多畴结构可以使VA模式的视角情况得到改善,但MVA模式中凸起结构引起的液晶分子初始预倾状态会导致暗态漏光,从而降低显示的对比度。而PVA模式中的狭缝结构虽然不会影响对比度,但其响应速度比较慢。文中提出一种新型垂面排列液晶显示器结构,其像素电极四周刻蚀有弧形狭缝,公共电极中心刻蚀有孔洞。施加电压时液晶分子向中心倾倒,形成中心对称的多畴结构,实现了对比度均匀的宽视角,且这一结构在保证高透过率的同时还可以实现快速响应。另外,通过在公共电极上施加偏置电压,该结构还可实现视角的连续可控。 相似文献
190.