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Emil S. Koteles 《Fiber and Integrated Optics》1999,18(4):211-244
A review is presented of state-of-the-art optical planar waveguide demultiplexers (DEMUXes), that is, phasars (arrayed waveguide) and etched grating devices designed for high-density (narrow channel spacing) wavelength division multiplexing (WDM) systems. Their advantages and disadvantages are discussed in comparison with other techniques for demultiplexing WDM signals. The advances made in their performance are reviewed, and ultimate limitations, set by technological constraints, are proposed. Finally, a comparison is made of the advantages and disadvantages of etched grating as opposed to phasar planar waveguide DEMUXes. 相似文献
3.
Qiankai Wang 《Optik》2013,124(24):6874-6876
The angular dispersion of four-sides prism is presented. A more accurate amended expression of measuring the wavelength of light wave with the spacing between two spectral lines is presented. The spacing between two spectral lines is measured with measuring microscope, the wavelength of light wave is calculated with the amended expression, the experimental values of wavelengths agree well with the reference value. 相似文献
4.
阐述SPD-I型全息凹面衍射光栅平场摄谱仪的基本工作原理和仪器结构,详细报导了该仪器的适用波长范围、平直谱面长度、倒数线色散率和光谱带宽等主要技术性能的光学测试方法和实验结果。测量结果表明在设计波长范围(400至800mm)内像差校正良好,获得的平直谱面可与光敏面长度为一英寸(23.5cm)的多通道探测器相配;仪器的色散相当均匀(约17nm/mm),在579.96nm波长处测得的光谱带宽为1nm,能满足一般光学多通道分析仪的要求。 相似文献
5.
Angular distributions for the 163Dy(t,p) and 177Hf(t,p) reactions were measured using 17 MeV tritons from the McMaster University Tandem Van de Graaff accelerator. Reaction products were analyzed with a magnetic spectrograph and detected with photographic emulsions. Favored L=0 transitions confirmed assignments of the 5/2−[523] band in 165Dy and 7/2−[514] band in 179Hf. Additional L=0 transitions in each nuclide identified previously unknown 5/2− levels in 165Dy and 7/2− ones in 179Hf. Overall trends of L=0 strengths support the existence of subshell closures at neutron numbers 98 and 108. On the basis of a relatively strong L=2 transition, the Kπ=11/2− γ-vibration based on the 7/2−[514] state is identified at 1689 keV in 179Hf, about 440 keV above its previously-assigned Kπ=3/2− partner. 相似文献
6.
指出了文献[1]在物理概念上和公式推导中的错误,并在订正了这些错误之后,考虑了实际的激光等离子体光源的几何尺度和线状等离子体的安排,对在复合泵浦X激光增益实验中所使用的带超环面镜X光中继元件的掠入射光栅光谱仪系统进行了全面的模拟计算.结果表明,作者所使用的带超环面镜的X光增益测试系统,其因离焦而导致的非线性效应是完全可以忽略的,系统的空间分辨能力的下降也是非常小的,从而否定了文献[1]中的结论,表明作者在X激光增益测量实验中所使用的带超环面镜X光中继元件的掠入射光栅光谱仪系统是完全可靠的. 相似文献
7.
V. Wilquet A. Mahieux V.I. Perevalov A. Fedorova F. Montmessin R. Dahoo J.-L. Bertaux 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(6):895-905
CO2 is the major constituent of the atmosphere of Venus. Absorption lines due to its 12C16O18O isotopologue have been observed for the first time in Venus spectra in the 2930-3015 cm−1 spectral region, where the HITRAN database does not contain any line from this isotopologue. The measurements were performed by the SOIR instrument, which is part of the SPICAV/SOIR instrument on board the Venus Express mission of ESA. SOIR measured the atmospheric transmission of the upper atmosphere of Venus (z>70 km) by performing a solar occultation experiment using the atmosphere as a gigantic absorption cell. The identification of this newly observed band was first made recently from Mars atmosphere observations by US colleagues. We have made independent theoretical calculations of the positions of the lines of this new 01111-00001 absorption band, which coincide perfectly with the positions of the observed lines. Assuming an oxygen isotopic ratio similar to the one measured previously in the lower atmosphere of Venus, the line strengths of each observed line are deduced and listed. 相似文献
8.
The spectrum of theB 2Σ-X 2Σ system of the CaF molecule has been photographed in the second order of a 10.6 m concave grating spectrograph with 0.33 Å/mm dispersion. The rotational structure of the (0, 0) and (1, 0) bands has been analysed and the precise molecular constants have been obtained. Using the constants so determined the band origins of a large number of bands with 0 <v′,v″ < 10 have been calculated and used to obtain the accurate vibrational constants forB andX states and these are presented. 相似文献
9.
《应用光谱学评论》2013,48(1):89-117
ABSTRACT This review describes, in detail, the most recent developments in instrumentation for laser induced breakdown spectroscopy (LIBS). The paper focuses on various laser systems, including excimer, CO2, and Nd: YAG and their performance in LIBS. The coupling of fiber-optics to LIBS and development of portable LIBS systems and their performance is presented. New approaches such as dual pulse operation, multi-fiber, resonant ablation, and combination with laser induced fluorescence are further described. Finally the use of the Echelle spectrometer in which it has been combined with various charge coupled devices. 相似文献
10.