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21.
Three advanced CIELAB-based color-difference formulae, CMC, CIE94, and CIEDE2000, together with the basic CIELAB equation, were tested using large color-difference visual data (maximum average size was 12 CIELAB ΔE units) produced in this study. The color-difference comparison experiment was carried out at CIE Gray and Blue centers by a panel of 6 normal color-vision observers using CRT-generated stimuli based on the psychophysical method of constant stimuli. The experimental data, processed via probit analysis, were well fitted to chromaticity ellipses with a high reliance according to the observer accuracy in terms ofPF/3 measure. A detailed comparison was performed to analyze the agreement between predicted color differences from all formulae and their corresponding visual scales in all measurement planes of CIELAB space. The results show that the CIEDE2000 marginally outperformed the others at all color centers while CIE94 was the worst in original formulae or with optimizedk L value, but the CIELAB performed worst when the parametric factors ofk L,kc, andk H were all optimized, with the CMC always lying between these extremes.  相似文献   
22.
The Rapid Cycling Synchrotron (RCS) is a key component of the China Spallation Neutron Source (CSNS). For this type of high intensity proton synchrotron, the chromaticity, space charge effects, and magnetic field tracking errors between the quadrupoles and the dipoles can induce beta function distortion and tune shift, and induce resonances. In this paper, the combined effects of chromaticity, magnetic field tracking errors and space charge on beam dynamics at CSNS/RCS are studied systemically. 3-D simulations with different magnetic field tracking errors are performed by using the code ORBIT, and the simulation results are compared with the case without tracking errors.  相似文献   
23.
彩色PDP中荧光粉发光色坐标的测量方法研究   总被引:4,自引:2,他引:2  
等离子体显示器已成为平板显示领域主要发展方向之一。在等离子体显示器上测得的色坐标包含了两部分:一部分是荧光粉在PDP器件中发光色的色坐标,一部分是PDP工作时气体放电的色坐标。在PDP屏的制作过程中,荧光粉经历了浆料制备、干燥、烧结以及老炼等工艺过程。因此,荧光粉在PDP屏上表现出的色坐标比起荧光粉体来说会产生一些变化。本文以测量PDP中荧光粉发光色坐标为目的,提出了一种用单色PDP屏色坐标、亮度和同结构下气体放电色坐标、亮度来获得荧光粉在PDP屏中色坐标和亮度的方法,设计制作了测试PDP屏三基色荧光粉发光色坐标所用的单色试验屏。用CRT ColorAnalyzer(CA-100)时PDP屏和PDP屏上气体放电产生的亮度和色坐标都进行了测量,根据合成颜色的在刺激值与二种已知颜色的在刺激值具有线性叠加关系,计算出了荧光粉在PDP器件中的色坐标和亮度。同时,用WGD-3型组合式多功能光栅光谱仪对PDP屏和气体放电的发光光谱进行了测量,用计算机将测得的发光光谱在同波长下相减,从而获得了荧光粉在PDP中的发光光谱。结果表明绿粉和蓝粉的色坐标变化较大,而红粉变化较小,使得PDP白场色温向较低的方向变化。绿粉和蓝粉的发光谱线的半峰宽与原粉比较都有减小,峰值发光强度也减小了,绿粉的峰值发光波长从526nm变至523.4nm。  相似文献   
24.
彩色图像中颜色不变性和耀斑的分离(Ⅰ)   总被引:2,自引:0,他引:2  
黄玉明  徐光佑 《光学学报》1991,11(11):041-1045
景物中物体表面的色品是与该物体形状无关的稳定特性,称为颜色不变性。但是,由于耀斑(highlight)和影绸(shading)的存在,图像中对应物体表面点的色品却是变化的,不具有颜色不变性。正确理解图像颜色的基础是建立颜色反射的物理模型。本文叙述了根据Klinker提出的双色反射模型(the dichromatic reflection model),在三维颜色直方图(3D color histogram)中利用K-L变换做平面拟合,分离面反射分量(interface reflection component)和体反射分量(body reflection component),从而计算光源和物体颜色色度坐标的方法,讨论了实际CCD摄像机的局限性,给出了实验结果。  相似文献   
25.
In掺杂ZnO薄膜的制备及其白光发射机理   总被引:1,自引:0,他引:1       下载免费PDF全文
李世帅  张仲  黄金昭  冯秀鹏  刘如喜 《物理学报》2011,60(9):97405-097405
采用溶胶-凝胶法在Si衬底上制备了本征ZnO薄膜和In:(Zn+In)分别为5%,8%,10%的ZnO薄膜,对薄膜的晶相结构和光电性质进行了表征并在CIE-XYZ表色系统中计算了不同样品的色品坐标.结果表明:In掺入后ZnO薄膜的择优生长方向由(002)面变为(101)面且面间距变小,当In掺杂量为5%时,In原子完全替代Zn原子;薄膜的电阻率随In含量的增加出现先抑后扬的趋势;随着In的掺入光谱的紫外发射峰红移,并在670 nm左右出现一个新的峰值;In:(Zn+In)为5%样品具有白光发射特性.从第一 关键词: In掺杂ZnO薄膜 溶胶-凝胶 色品坐标 白光发射  相似文献   
26.
王瑗  黄耀清  杨文明  赵铁松 《大学物理》2005,24(9):50-53,56
介绍一种由三色发光二极管和导光板组成的适合物理实验色度测量教学的彩色面光源,并给出了测量该光源色度的实验方法.  相似文献   
27.
单个油气包裹体的紫外-可见显微荧光光谱及色度研究   总被引:1,自引:0,他引:1  
将倒置荧光显微镜、反射式显微物镜、微透镜、光纤和荧光分光光度计等有机地融合为一体,建立了测量单个油气包裹体的紫外-可见显微荧光光谱装置,该装置无需对显微镜做任何技术改造.实测了伏4井(泉三段,吉林油田)单个油气包裹体的紫外-可见显微荧光光谱.通过250 nm激发下的荧光光谱定性地推测油气包裹体中古油所含芳烃主成分,结果...  相似文献   
28.
The complex obtained by condensation of salicylideneaniline with copper(II) acetate was studied in a variety of solvents. This deep-brown crystalline compound is soluble in common solvents, such as, chloroform, toluene, dioxane, methanol, ethanol, dimethyl formamide, dimethyl sulfoxide, and acetonitrile—a necessary condition for observing solvatochromism. The complex has been characterized by elemental analysis, molar conductivity, EPR, and ultraviolet (UV) and visible (VIS) spectroscopy. The available X-ray data shows planar coordination geometry for the copper center. Combined multi-technique experiments have been applied to confirm the structure of the complex in solution. The molar conductivities indicate nonelectrolytic properties. EPR measurements preclude the possibility of solvent coordination at the axial positions of the complex. Spectroscopic measurements were used to study the coordination properties of donor atoms and their bonding ability, as well as trichromaticity coordinate calculations. The results obtained show that the interactions of metal with donors depend on donor strength and polarity of solvent.  相似文献   
29.
The chromoaticity colorimetry has been applied to the study of CoBr2 solutions color in organic solvents. The values of chroroaticity coordinates have been determinated from absorption spectra. It was stated that the ability to form cobalt(II) complex ions of particular symmetry is consequence of donor-acceptor properties of the solvents. The tendency to form the tetrahedral ions has been observed in the solvents described by low acceptor number (AN < 30). In the solvents with AN > 30 the participation of the tetrahedral form in the mixture with the octahedral one increases with the increase of the complementary wavelength.  相似文献   
30.
The Rapid Cycling Synchrotron (RCS) is a key component of the China Spallation Neutron Source (CSNS). For this type of high intensity proton synchrotron, the chromaticity, space charge effects, and magnetic field tracking errors between the quadrupoles and the dipoles can induce beta function distortion and tune shift, and induce resonances. In this paper, the combined effects of chromaticity, magnetic field tracking errors and space charge on beam dynamics at CSNS/RCS are studied systemically. 3-D simulations with different magnetic field tracking errors are performed by using the code ORBIT, and the simulation results are compared with the case without tracking errors.  相似文献   
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