中国科学院机构知识库网格系统: 检索

Chromatic analysis of harmonic Fresnel lenses by FDTD and angular spectrum methods 期刊论文 OAI收割
Applied Optics, 2018, 卷号: 57, 期号: 19, 页码: 5281-5287
作者: Yang, Jianming; Twardowski, Patrice; Gerard, Philippe; Yu, Wenhui; Fontaine, Joel

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收藏 | 浏览/下载：24/0 | 提交时间：2019/09/17

Time domain analysis Angle measurement Diffraction efficiency Efficiency Finite difference time domain method Full width at half maximum Harmonic analysis Optical instrument lenses Refractive index Spectrum analysis

Non-Contact Measurements of Water Jet Spreading Width with a Laser Instrument 期刊论文 OAI收割
2016
作者: Funami, Y., Hasuya, R., Tanabe, K. and Nakanishi, Y.

收藏 | 浏览/下载：33/0 | 提交时间：2017/05/27

Water jet Jet spreading width Jet taper Non-contact measurement Laser instrument air Thermodynamics Engineering

High density print circuit board line width measurement algorithm based on statistical process control theory 期刊论文 OAI收割
OPTIK, 2013, 卷号: 124, 期号: 20, 页码: 4472-4476
作者: Zhang, Jing; Ye, Yutang; Xie, Yu; Liu, Lin; Chang, Yongxin

收藏 | 浏览/下载：26/0 | 提交时间：2015/04/17

High-density circuit board Line width measurement Morphological erosion operator Clustering segmentation Measure system analysis

Leaf shape alters the coefficients of leaf area estimation models for Saussurea stoliczkai in central Tibet 期刊论文 OAI收割
PHOTOSYNTHETICA, 2012, 卷号: 50, 期号: 3, 页码: 337-342
Wang Z (Wang, Z.); Zhang L (张林)

收藏 | 浏览/下载：18/0 | 提交时间：2013/05/23

LINEAR MEASUREMENTS ALLOMETRIC MODELS WIDTH MEASUREMENT PREDICTION MODEL L. SIZE REGRESSION MORPHOLOGY CULTIVARS LENGTH

Allometric models for leaf area estimation across different leaf-age groups of evergreen broadleaved trees in a subtropical forest 期刊论文 OAI收割
PHOTOSYNTHETICA, 2011, 卷号: 49, 期号: 2, 页码: 219-226
Zhang L (张林); Pan, L (Pan L.)

收藏 | 浏览/下载：17/0 | 提交时间：2012/05/10

LINEAR MEASUREMENTS NONDESTRUCTIVE METHODS WIDTH MEASUREMENT L. ACCURATE REGRESSION CITRUS LENGTH

Effect of thickness on the structural, electrical and optical properties of ZnO films deposited by MBE (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Advanced Design and Manufacturing Engineering, ADME 2011, September 16, 2011 - September 18, 2011, Guangzhou, China
Yang X.; Su S.; Yi X.; Mei T.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

A set of ZnO films of different thickness have been deposited on sapphire substrates using molecular beam epitaxy (MBE) by varying the growth time and the effect of film thickness on the structural electrical and optical properties have been investigated. The X-ray diffraction (XRD) results indicate that the full width at half maximum (FWHM) of the (002) diffraction peak is decreased as the film thickness increasing and the stress along c-axis is stable. Scanning electron microscope (SEM) measurement shows that the grains become more uniform as the film grows thicker and the film surface present distinct hexagon shape as the film is grown up to a thickness of 500nm. The optical absorbance Hall mobility and photoluminescence (PL) intensity are increased in accordance with the thickness of the film. (2011) Trans Tech Publications Switzerland.

The Research of real time auto-recognition of the moire fringe (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Wang M.-J.; Wu Z.-G.

收藏 | 浏览/下载：19/0 | 提交时间：2013/03/25

Measuring the movement of raster by the method of moire fringe has the advantage of high sensitivity high resolution and non-contacted measurement. The characteristic of moire fringe is that the image is white alternate with black the angle of the stripes is uniform the width of the stripes is uniform the terminators of the stripes aren't clear. A fast method that can figure out the width and angle of the moire fringe precisely is put forward in this paper. It calculates the angle the stripes firstly. According to the principle of the minimum mean squared error (MMSE) the closer a series of data is the smaller the value of the MMSE will be. The method is described as follows: It takes the image's center as the origin 180 beelines pass through the origin with the same angle interval. it calculates the value of the minimum mean squared error of the 180 beelines and find out the least one among those then the angle of the moire fringe comes out primarily. In order to improving the calculating precision of moire fringe 60 equal angles are divided in the neighborhood of the angle then a precise angle of moire fringe is calculated according to the principle of the MMSE. After getting out the angle of the moire fringe we begin to calculate the width of moire fringe. A line vertical with the moire fringe is drawn and we can get the width of the moire fringe by the vertical line. In order to get over the influence of the noise an effective area with the shape of diamond is selected in the image. The data of area is accumulated and projected according to the direction of moire fringe and a sine curve come out. The width of moire fringe can be obtained by getting the position of the first wave crest the position of the last wave crest and the number of wave crest. Experiments prove that the precision of the method put forward in this paper is enhanced in comparison with the traditional frequency method the precision of width calculation achieves to 99.6% according to the evaluation indicators of width detection error. The computing speed is boosted largely compared with traditional method and it can achieve with 15 ms that satisfying the demand of real time. 2011 SPIE.

Design of co-path scanning long trace profiler for measurement of X-ray space optical elements (EI CONFERENCE) 会议论文 OAI收割
6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China
Shun L.; Yan G.; Wei Z.; Yang Z.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

The Long Trace Profiler (LTP) is a precision surface slope error measurement instrument used in synchrotron radiation optics for many years. By making some modifications to the LTP system we developed a co-path scanning LTP (CSLTP) system to test the cylindrical aspherical surface which used in X-ray space optics. To reduce the mistake caused by air turbulence and manufacture faults of optical elements used the CSLTP is designed with the least difference between the testing beam path and the reference beam path. Also it uses multiple-beam interference but double beam interference to reduce the width of beam fringe. This improves the position precision of the beam fringe on the image plane. 2010 SPIE.

Studies of back-streaming white neutrons at CSNS 期刊论文 OAI收割
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT, 2010, 卷号: 621, 期号: 1-3, 页码: #REF!
作者: Jing HT(敬罕涛); Tang JY(唐靖宇); Jing, HT; Tang, JY; Tang, HQ

收藏 | 浏览/下载：27/0 | 提交时间：2016/04/12

Spallation neutron source Back-streaming neutrons Neutron yield Pulse width Nuclear data measurement

Three-dimensional angle measurement based on auto-collimation and moire fringe (EI CONFERENCE) 会议论文 OAI收割
2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China
Cai S.; Liang S.; Qiao Y.-F.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

A method for small three-dimensional (3D) angle measurement based on auto-collimation and moire fringe is proposed and analyzed. A right-angle prism is used as the indicator of angle change. The inclined plane indicates the pitch and yaw angles and roll angle in indicated by the rib which is the intersection of two right-angle sides. Pitch and yaw angles measurement are implemented by auto-collimation based on reticule and roll angle measurement is measured based on moire fringe. Roll angle measurement is separated from pitch and yaw by using two light sources with different frequencies. Any small change of pitch and roll angles will induce the shift of the reticule image after reflecting by inclined plane. And any small roll angle will induce a change in moire fringe width that is generated by scale grating image which is reflected by the prism and index grating. The math model of this method is built up and error analysis is presented. The theoretical calculation results show that the proposed method is feasible and can achieve high accuracy. 2009 SPIE.