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191.
192.
Yasunori Igasaki Fanghong Li Narihiro Yoshida Haruyoshi Toyoda Takashi Inoue Naohisa Mukohzaka Yuji Kobayashi Tsutomu Hara 《Optical Review》1999,6(4):339-344
To realize a high efficiency electrically addressable phase-only modulator, we have coupled a liquid crystal display (LCD) to an optically addressed parallel-aligned nematic liquid crystal spatial light modulator (PAL-SLM) with a set of lenses. Phase modulation exceeding 3ϖ at 532 nm wavelength was obtained. We obtained linear transfer characteristics for phase modulation at various desired phase levels after calibration and adjustment of the transfer characteristics of the PAL-SLM and the LCD. Diffraction efficiency of 40% for binary phase grating and of 90% for 8-level blazed phase grating, which were very close to the simulation values, were observed. The power loss of the readout light was caused when passed through a half mirror, therefore, we examined a setup using an oblique readout light at the modulator. Very high diffraction efficiency was obtained from the setup by optimizing the polarization direction and optical path for this light, and the orientation of liquid crystals. Since the modulator can perform at better than 90% diffraction efficiency and at nearly 100% reflectivity, various high efficiency systems utilizing such modulators are expected. 相似文献
193.
The mechanism of the graphics distrotion in a laser display system was studied. Based on the mathematical analysis, the pincushion and linear distortions were calculated. Theoretical results agree well with the experimental observation. By tracing laser beams from image plan back to scanners, a relation between the image points on the screen and the scan angles was built. Thus, it has been able to rectify the scanning distortions by computer software effectively. 相似文献
194.
A new solid-state NMR pulse sequence for recoupling 13C–1H dipolar interactions under magic-angle spinning is proposed, which works under a spinning speed of a few to several tens kilohertz. The sequence is composed of two different frequency switched Lee–Goldburg sequences, and the modulation of the spin part of the 13C–1H dipolar interaction is introduced by a virtual pulse sequence consisting of unitary operators connecting the rotating frame and the tilted rotating frame. When the cycle time of the spinning is equal to or twice the cycle time of the sequence, the 13C–1H dipolar interactions can be recoupled. The sequence is insensitive to experimental imperfections such as rf inhomogeneity or frequency offset, and the resulting lineshape can be represented by a simple analytical equation based on the zeroth-order average Hamiltonian. Experimental results for [2-13C]
-valine·HCl are reported. 相似文献
195.
196.
Pravinraj Selvaraj Wen-Fa Cheng Hsiu-Ming Kuo Cheng-Kai Liu Chao-Hsuan Wu Chung Kung Lai Jyun-Cong Lai Sharon Tan Fang Jie Ko-Ting Cheng 《Laser \u0026amp; Photonics Reviews》2024,18(5):2301001
Smart windows are crucial to dynamic control over light transmission to fulfill various demands in energy saving, privacy, and information display; however, most present technologies still perform a single function (often tint or haze adjustment) and require continuous electricity for operation. In this study, novel self-assembled ionic liquid crystals (ILCs) doped with negative cholesteric liquid crystals (CLCs) to offer electrically switchable and stable scattering-mode light modulators are presented. The novel smectic A phase based on the ILCs exhibits high solubility in the adopted nematics, enhancing the LC device's performance in several ways, including improved homogeneity, stable alignment quality, prolonged stability, and simplified fabrication. The LC device can potentially offer a dynamically rapid switching function between stable transparent (imperfect fingerprint textures) states and stable scattering (focal conic textures with small domains) states by using external stimuli and highly maintained multistable states for prolonged periods, even when the external stimuli are removed. The LC device also offers polarization-independent scattering and transparent-mode LC light modulators, low operating voltage, excellent contrast, and broad viewing angles. Its versatility and outstanding field-off stability make it ideal for various applications such as smart lighting, building climate control, energy-saving displays, and augmented reality (AR) glasses. 相似文献
197.
印刷有机电子技术是基于印刷原理的有机电子器件制造技术,是指将有机电子材料配制成功能性油墨,用印刷方式来制造电子器件与系统的方法,其发展涉及到材料化学、微电子学等多个学科方面的知识。其独特的制造方式和器件形态具有柔性、低成本、大面积制造等优势,并且与传统硅基电子器件在应用场合上形成了互补,在生物传感、电子皮肤、柔性显示等领域展示出优势。为了及时跟进这一快速发展的领域,对领域的发展有宏观的把握,本文从印刷技术和电路系统的角度进行了全面概述,介绍了喷墨打印、丝网印刷和转印印刷等印刷技术和基于印刷技术制备的有机数字电路(反相器、与非门、环形振荡器、D触发器),以及实现功能化的印刷电子应用(RFID、电子皮肤、OLED显示驱动背板等);最后,对本领域目前存在的问题和未来发展方向做了简要探讨。 相似文献
198.
Naoki Toshima 《Macromolecular Symposia》2003,204(1):219-226
Due to a nanotechnology boom in science and technology, the metal nanoclusters or nanoparticles stabilized by polymers and organic ligands have achieved much attention recently all over the world. We have studied on the preparation of polymer-stabilized metal nanoclusters by chemical methods, and applied them mainly to catalyses. Here the recent progresses in our group are presented in the structure control of bimetallic and trimetallic nanoclusters and in the applications of metal nanoclusters not only to the catalyses but also to the sensing responsive to pH and molecular recognition, and to the electro-optic properties of liquid-crystalline display rapidly responsive to frequency modulation. Preparation of trimetallic nanoclusters with a triple core/shell structure is especially emphasized to serve as a very active catalyst at a special atomic ratio of three elements. 相似文献
199.
Yasushi Ohe Makoto Kume Yasuyuki Demachi Takao Taguchi Kunihiro Ichimura 《先进技术聚合物》1999,10(9):544-553
A novel photopolymer for fabrication of high‐resolution volume holograms, which primarily are used on holographic optical elements such as head‐up display (HUD), is reported. This photopolymer consists of bisphenol‐type epoxy resin and radically polymerizable aliphatic monomer with diaryliodonium salt and 3‐ketocoumarin (KCD) as a complex initiator. The chemistry of imaging formation is based on the radical polymerization of the monomer initiated by a holographic exposure, following by the cationic polymerization of epoxy resin by UV‐exposure after post‐exposure baking. The yellowish color of hologram derived from KCD, the shape of peak of reconstructed light and the blue shift of wavelength of reconstructed light, were improved in order to satisfy the specifications for the combiner of HUD. A stand type holographic HUD system as an example of automotive display attached on the dashboard of an automobile is demonstrated. The display gives a high contrast image, and the combiner has good durability. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
200.
Microtubules are tube-shaped, filamentous and cytoskeletal proteins that are essential in all eukaryotic cells. Microtubule is an attractive and promising target for anticancer agents. In this study, three-dimensional quantitative structure activity relationships (3D-QSAR) including comparative molecular field analysis, CoMFA, and comparative molecular similarity indices analysis, CoMSIA, were performed on a set of 45 (E)-N-Aryl-2-ethene-sulfonamide analogues as microtubule-targeted anti-prostate cancer agents. Automated grid potential analysis, AutoGPA module in Molecular Operating Environment 2009.10 (MOE) as a new 3D-QSAR approach with the pharmacophore-based alignment was carried out on the same dataset. AutoGPA-based 3D-QSAR model yielded better prediction parameters than CoMFA and CoMSIA. Based on the contour maps generated from the models, some key features were identified in (E)-N-Aryl-2-arylethene-sulfonamide analogues that were responsible for the anti-cancer activity. Virtual screening was performed based on pharmacophore modeling and molecular docking to identify the new inhibitors from ZINC database. Seven top ranked compounds were found based on Gold score fitness function. In silico ADMET studies were performed on compounds retrieved from virtual screening in compliance with the standard ranges. 相似文献