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Laser Beam Shaping in Array-Type Laser Printing Systems
Published in Fred M. Dickey, Scott C. Holswade, David L. Shealy, Laser Beam Shaping Applications, 2018
Andrew F. Kurtz, Daniel D. Haas
In cases where the laser array is directly addressed and directly imaged to the media with largely spherical optics, the spot-to-spot pitch will be largely determined by the laser array fabrication process, and the array printing (slow scan) and cross array printing (fast scan) directions will generally see similar optical tolerances. The fast scan motion of the drum or media will tend to blur the spot in the cross array direction, potentially easing those tolerances. If the print-head is integrated as a closely packed array of spots, then there will be swath-to-swath positioning tolerances, driven by the need to minimizing a visual artifact known as banding.
Laser Beam Shaping in Array-Type Laser Printing Systems
Published in Fred M. Dickey, Todd E. Lizotte, Laser Beam Shaping Applications, 2017
Andrew F. Kurtz, Daniel D. Haas, Nissim Pilossof
In cases where the laser array is directly addressed and directly imaged to the media with largely spherical optics, the spot-to-spot pitch will be largely determined by the laser array fabrication process, and the array printing (slow scan) and cross-array printing (fast scan) directions will generally see similar optical tolerances. The fast scan motion of the drum or media will tend to blur the spot in the cross-array direction, potentially easing those tolerances. If the print-head is integrated as a closely packed array of spots, then there will be swath-to-swath positioning tolerances, driven by the need to minimize a visual artifact known as banding.
From Graphics to Visualization
Published in Alexandru Telea, Data Visualization, 2014
However attractive, this rendering of the surface approximation has several limitations. Probably the most salient one is the “faceted” surface appearance, due to its approximation by flat-shaded quadrilaterals. This artifact is visible even when we use a relatively densely sampled dataset, such as the one in Figure 2.2. When using flat-shaded polygons, removing this visual artifact completely for a height plot of an arbitrary function implies rendering polygons with a size of one pixel. In our setup, this implies, in its turn, using a prohibitively high sampling density. Just to give an impression of the costs, on a screen of 640 × 480 pixels, this strategy would require rendering over a hundred thousand polygons, and computing and storing a dataset of over a hundred thousand sample points, i.e., a memory consumption of a few hundred kilobytes, all for a simple visualization task.
Improvement of the dynamic responses of liquid crystal mixtures through γ-Fe2O3 nanoparticle doping and driving mode adjustment
Published in Liquid Crystals, 2019
Yayu Dai, Lin Gao, Mohan Wang, Xueqian Zhao, Tong Li, Zongyuan Tang, Zhenjie Li, Hongyu Xing, Jiliang Zhu, Wenjiang Ye, Xiangshen Meng, Zhenghong He, Jian Li, Minglei Cai, Changyong Yang
Liquid crystals (LCs) exhibit crystal anisotropy and fluidity. These materials have a crucial role in promoting the development of adaptive and integrated optics given their extensive uses in display, phase modulation, information storage, optical switching, and optical communication [1–5]. LCDs have been widely used in flat-panel display devices because of their advantages of low power consumption, light weight, facile driving, and high resolution. The current response time of LCDs, however, is long and on the order of milliseconds. This characteristic is a weakness that limits the performance of LCDs [6,7]. Response time has become an urgent problem that requires resolution as consumer demand for LCDs with high image quality continues to increase. The response time of LCDs is defined as the time required for LC molecules to begin rotating until they return to the state with the lowest free energy density during voltage application and withdrawal. Response time determines the minimum time required to display one image frame and is an important parameter of LCDs. If the response times of LCDs are excessively long, then the viscosity of LC materials can cause each pixel display unit to generate a response delay that is longer than the time required to display successive frames. Thus, the previous frame is superimposed as an afterimage on the next frame. The afterimage degrades image motion and display quality and introduces image and visual artifacts, such as ghost images. The fast response characteristics of LCs must be explored to develop approaches for reducing motion blurring and tailing, controlling field sequence color, and improving the low-temperature performance and display clarity and smoothness of LCD devices.