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2.
A displacement interferometer is described for measuring gauge blocks, in which a spatial filter is used to combine a laser
beam with a white-light beam, and the length of the block is calculated from the phase differences of the laser signal corresponding
to the centers of gravity of the achromatic fringes from the gauge and from the reference plate.
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Translated from Izmeritel’naya Tekhnika, No. 9, pp. 3–5, September, 2006. 相似文献
3.
An adaptive color similarity function suitable for image segmentation and its numerical evaluation 下载免费PDF全文
Rodolfo Alvarado‐Cervantes Edgardo M. Felipe‐Riverón Vladislav Khartchenko Oleksiy Pogrebnyak 《Color research and application》2017,42(2):156-172
In this article, we present an adaptive color similarity function defined in a modified hue‐saturation‐intensity color space, which can be used directly as a metric to obtain pixel‐wise segmentation of color images among other applications. The color information of every pixel is integrated as a unit by an adaptive similarity function thus avoiding color information scattering. As a direct application we present an efficient interactive, supervised color segmentation method with linear complexity respect to the number of pixels of the input image. The process has three steps: (1) Manual selection of few pixels in a sample of the color to be segmented. (2) Automatic generation of the so called color similarity image (CSI), which is a gray level image with all the gray level tonalities associated with the selected color. (3) Automatic threshold of the CSI to obtain the final segmentation. The proposed technique is direct, simple and computationally inexpensive. The evaluation of the efficiency of the color segmentation method is presented showing good performance in all cases of study. A comparative study is made between the behavior of the proposed method and two comparable segmentation techniques in color images using (1) the Euclidean metric of the a* and b* color channels rejecting L* and (2) a probabilistic approach on a* and b* in the CIE L*a*b* color space. Our testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. It was obtained from the results that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume in the CIE L*a*b* color space. We show that our solution improves the quality of the proposed color segmentation technique and its quick result is significant with respect to other solutions found in the literature. The method also gives a good performance in low chromaticity, gray level and low contrast images. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 156–172, 2017 相似文献
4.
针对近红外光谱可对活体组织进行无损伤穿孔,并解决在穿孔中需要重新对焦的问题,通过Zemax软件对7片式前置光阑显微物镜结构在0.48~1.48?m波长范围内进行了宽光谱消色差的优化设计。设计实现了像距为无限远的多光谱共焦成像,其放大倍率为40,数值孔径0.5,最大焦面漂移量仅为27?m,可见光波段在空间频率为350 lp/mm时,0.7视场的MTF>0.5,具有较高的分辨力。并且在波长1480 nm处,MTF值接近衍射极限,具有较高的能量,满足细胞穿孔的要求。文中还给出了实验结果,并预测其应用前景。 相似文献
5.
论述了色彩在包装设计中的重要性,黑、白、灰、金银色等无彩色系与有彩色之间的配合,以及无彩色之间的相互配置关系.无彩色在包装上的运用对丰富包装设计效果是十分重要的. 相似文献
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This study explores the effects of chroma on participants' performance and environmental appraisal of an office. The research was conducted in a full‐scale experimental room designed as a private office where achromatic and chromatic color schemes with coequal values were applied. Sixty participants were assigned tasks and given a questionnaire to appraise the spatial color schemes. The findings show that chroma significantly affects performance and space appraisal. In terms of accuracy and time spent performance scores measured significantly better in the room with the chromatic scheme than those in the room with the achromatic scheme. The office with the chromatic scheme was found to be more pleasant, attractive, satisfying and dynamic than the one with the achromatic scheme, whereas the achromatic scheme was thought to be more formal and harmonious. Categorization of pleasantness, harmony, dynamism and spaciousness by factor analysis also showed differences between the achromatic and chromatic schemes. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2012 相似文献
8.
本文提出利用光栅产生类似多狭缝形式的带状谱获得消色像的全息记录方法,讨论了获得消色像的条件,并给出了实验结果。 相似文献
9.
压电移相器的空间旋转误差建模与实验分析 总被引:2,自引:0,他引:2
通过对压电移相器在微位移过程中端面旋转的数学建模,对其空间旋转误差进行了理论分析;基于该数学模型,利用泰曼一格林干涉系统对两种不同工艺制作的移相器进行了在线检测,根据干涉条纹的旋转及间距变化,可以定量分析高精度移相器在微位移移相过程中其端面的旋转角度以及空间任意点的位移误差,并给出了相关实验结果.表明:用该方法在线检测各种不同工艺制作的移相器,对其端面上任意点由于端面旋转引起的空间位移误差检测灵敏度达到pm量级.在0~100 V驱动电压范围内进行在线移相检测,实验测量移相器的位移精度优于λ/200,对应相移精度高于0.06 rad. 相似文献
10.
超构表面因其体积轻薄易于集成化,有望在某些特定场合取代传统透镜实现多功能光学器件。超构表面的光束偏转角随波长的增加而增大,与传统折射透镜相比产生相反的色散,这种色散又被称为“异常色散”或“负色散”。理论上利用超构表面的负色散和传统折射光学器件的正色散相抵消,可以完全矫正光学系统的色差。由此出发,设计了一种基于光刻胶材料,由Pancharatnam-Berry(PB)相位型超构表面作为第一透镜,传统球面透镜作为第二透镜的消色差超构表面复合透镜,利用时域有限差分数值模拟软件FDTD Solutions探索了该透镜在780~980 nm波段的聚焦性能,证明了消色差光刻胶超构表面复合透镜优异的消色差效果。相对传统的消色差超构表面通过相位补偿来消色差的方法,这种消色差设计简单且高效,为特定波段内的消色差成像提供了一定的借鉴意义。 相似文献