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131.
A parallel plate interferometer with a reflecting mirror for measuring angular displacement is proposed. A deflection angle
of a beam caused by an angular displacement is amplified by use of a reflecting mirror to increase the optical path difference
(OPD) in the plane-parallel plate, which provides high sensitivity of the phase measurement. Detection of light transmitted
through the plane-parallel plate with a position sensitive detector (PSD) enables high accurate measurement of the initial
angle of incidence to the plane-parallel plate with insensitivity to stray light. The improved parallel plate interferometer
achieves a measurement repeatability of 10−8 rad. 相似文献
132.
The real part of the effective index is enhanced in a metal-insulator-metal (MIM) surface plasmon waveguide when the thickness of the insulator is quite small and this mechanism can be utilized to achieve some ultra-compact photonic devices. The mode properties of an index-guided multimode plasmonic waveguide of subwavelength size are analyzed and the multimode interference (MMI) effect is investigated. A novel ultra-compact MMI power splitter, with the transverse size less than 1/3 of the free space wavelength, is proposed. 相似文献
133.
134.
This study proposes a common path interference optical system for the measurement of refractive indices and thickness of uniaxial crystal material. The measurement system comprises an accurate Mach–Zehnder laser interferometer, a single-axis rotary stepping motor, and a computer. The laser interferometer is composed of a single-frequency He–Ne laser, two-beam splitters and two reflectors. The Mach–Zehnder laser interferometer measures the optical length difference by using its linear measurement accuracy. The proposed solution procedure enables both the refractive indices and the thickness of the optical waveplate to be obtained. The proposed design differs from conventional designs in that it does not use a heterodyne modulator with a lock-in technique. It is shown that the refractive indices and thickness of the tested optical elements can be measured rapidly and accurately. 相似文献
135.
激光束照射到表面被粘污的反射镜上会产生干涉环,入射光束和反射光束在被粘污表面产生散射光干涉.随着入射角的变化,光束在反射镜玻璃片内光程改变,引起干涉环从中心冒出或缩进,干涉环级数的变化与入射角的平方成正比. 相似文献
136.
笔者被聘为2007年亚奥赛物理实验命题,经过半年多的努力终于将科研成果——激光测温合理地转换为一个奥赛实验试题——干涉法测量玻璃热膨胀系数和折射率温度系数,本文主要介绍了命题过程及体会. 相似文献
137.
Ryszard Struzak 《Annals of Operations Research》2001,107(1-4):339-347
This paper addresses the operation of radio links under mutual interference conditions, an important problem in spectrum management and radio link design. It introduces the capacity loss and isolation index as measures of effective use of radio links and radio frequency spectrum resources. 相似文献
138.
This paper proposes a multigrid technique for Cartesian grid flow solvers. A recently developed ghost body‐cell method for inviscid flows is combined with a nested‐level local refinement procedure, which employs multigrid to accelerate convergence to steady state. Different from standard multigrid applications for body‐fitted grids, a fictitious residual needs to be defined in the ghost cells to perform a correct residual collection and thus to avoid possible stalling of the multigrid procedure. The efficiency of the proposed local refinement multigrid Cartesian method is demonstrated for the case of the inviscid subsonic flow past a circular body. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
139.
This paper presents a simulation and an analytical modeling of the machine interference problem in manufacturing cells. Each machine experiences two types of stoppage which are to be served by a robot. Several combinations of the distributions of the stoppages, service distributions, and service disciplines are studied. We determine the optimal number of machines assigned to the robot under different operating conditions such that the expected total cost of the manufacturing cell is minimized.This research is based on Mr. Norton's M.S. thesis, which was conducted at Rutgers. 相似文献
140.
本文从理论上推导出双棱镜干涉实验中各参量的取值范围,并通过实验研究找到测量误差小于1%时各参量的取值,这为减小实验误差提供了理论和实验依据. 相似文献