共查询到20条相似文献,搜索用时 46 毫秒
1.
2.
The intensity distribution in the interference pattern of a multiple-slit aperture illuminated with the partially coherent light is examined experimentally. The experimental results showing excellent agreement with the theoretical predictions indicate both a gradual loss in the contrast of interference fringes and a broadening of the principal maximum fringes with decreasing spatial coherence of the illumination. 相似文献
3.
4.
The spatial coherence of an atomic wavepacket can be detected in scattered photons, even when the center-of-mass motion is in the quantum coherent superposition of two distant, nonoverlapping wavepackets. Spatial coherence manifests itself in the power spectrum of the emitted photons, whose spectral components can exhibit interference fringes as a function of the emission angle. The contrast and the phase of this interference pattern provide information about the quantum state of the center of mass of the scattering atom. 相似文献
5.
对部分相干光束的双缝实验干涉条纹进行了研究。利用转动的毛玻璃以及两个透镜构成了一个简单的产生部分相干光束的光学系统,通过调整毛玻璃与两个透镜的共焦点之间的距离,可以定量地控制光束的相干性。对不同相干性的光束经过双缝干涉之后的光强进行了实验观测,发现光束的相干性会对双缝干涉条纹的衬比度产生影响,光束的相干性越低,条纹衬比度也越小。并对实验结果进行了理论模拟,理论数值模拟的结果与实验观测结果基本一致。 相似文献
6.
基于机器视觉系统OpenMV,以迈克耳孙干涉仪干涉条纹为研究识别对象,根据光源相干性及干涉条纹动态特性,提出基于灰度采样统计的干涉条纹识别检测算法(干涉条纹同心形态搜索算法),运用MicroPython或Python语言编制实时检测程序,运行结果表明仿真和真实干涉条纹都得到了可靠的检测,精度为0.5个条纹,并且测量不确... 相似文献
7.
The process of interference-pattern image formation in an optical system with a random phase screen in the space-frequency plane is analyzed. It is shown that an optical system of this kind can function, under certain conditions, as a shearing interferometer, which determines the dependence of contrast of the average intensity fringes in the interference pattern image on the normalized correlation function of the random phase screen complex transmittance. The dependence of the fringe contrast on the pattern period and aperture of the field of view is established, as well as dependence of the optical transfer function of the system under study on spatial coherence of the light in the pupil of the system with the random phase screen. 相似文献
8.
We derive a spectral interference law that governs the behavior of the four Stokes parameters in Young's two-pinhole experiment with a random electromagnetic beam. In addition to the visibility of intensity fringes, we introduce three new contrast parameters that describe the interference-induced changes in the field's state of partial polarization. The polarization modulation depends on the electric field correlations at the pinholes and is closely related to the two-point Stokes parameters. The results are expected to be particularly useful in polarization interferometry and electromagnetic coherence theory. The formalism is demonstrated with specific examples. 相似文献
9.
It is shown how surface plasmons that travel between the slits in Young's interference experiment can change the state of spatial coherence of the field that is radiated by the two apertures. Surprisingly, the coherence can both be increased and decreased, depending on the slit separation distance. This results in a modulation of the visibility of the interference fringes. Since many properties of a light field-such as its spectrum, polarization, and directionality - may change on propagation and are dependent on the spatial coherence of the source, our results suggest that the use of surface plasmons provides a new way to alter or even tailor the statistical properties of a light field. 相似文献
10.
11.
本文应用电子光学与几何光学的相似性,从光程的计算出发,求出了电子经Mllenstedt双棱镜的偏转角,并与光学中菲涅耳(Fresnel)双棱镜进行了比较。讨论了电子束源的部分相干性对干涉场的影响,给出通过电子干涉得到的各量的表达式。 相似文献
12.
13.
14.
可获得高衬比干涉条纹的实时全息记录方法 总被引:13,自引:3,他引:10
本文提出了一种可以获得高衬比的实时全息记录方法,它通过分析所记录的第一张实时全息图来获得拍摄最佳衬比实时全息图的拍摄参数,文中指出了拍摄最佳衬比实时全息图需要满足的条件,给出了理论分析和实验验证,实验结果与理论相符甚好,对于透明物体的实时法全息图.条纹衬比可接近最佳值1. 相似文献
15.
干涉效应反映了光场的相干性,非相干光源中无序性会破坏干涉.然而对于高阶干涉来说这一看法并不成立.文章作者最近的理论和实验研究表明,横向传播方向无序的热光源可以实现高阶双缝干涉.尽管单个探测器的强度分布是均匀的,处于不同位置的两个探测器的联合强度关联却出现了干涉条纹.当两个探测器同步反向移动时,条纹间距减小为一阶干涉条纹的一半.实验结果同不久前报道的在自发参量下转换过程中产生的纠缠双光子对的双缝实验中所观察到的亚波长干涉效应十分类似.实验结果可以用多模热光场的二阶空间关联性质来解释.热光的高阶双缝干涉是著名的Hanbury-Brown和Twiss实验的空间干涉版本,因此也可称其为Hanbury-Brown和Twiss型双缝干涉。 相似文献
16.
17.
Static interference fringes were observed repeatedly with changes of path difference in both homodyne and heterodyne Michelson interferometers. This unique coherence property of an electronically tuned Ti:sapphire laser with an intracavity acousto-optic tunable filter (AOTF) has revealed the frequency structure and dynamics of the laser field. The fact that static interference occurred in a heterodyne interferometer with unequal path lengths indicates backscattering of the intracavity laser field, suggesting that Brillouin-enhanced four-wave mixing occurs in the intracavity AOTF. 相似文献
18.
One drawback of Michelson's stellar interferometer is due to the fact that the period of the interference fringes is proportional to the wavelength. Hence, in broadband light the fringe contrast is low, or in narrowband light (after filtering) the luminosity is low. We propose a modified stellar interferometer with perfectly achromatic fringes, that has better light efficiency and better signal to noise under most circumstances. To that end, two pieces of grating have to fill the two apertures of Michelson's setup. Achromatic interference fringes occur somewhere along the system axis, where the plus-first diffraction order from one aperture meets the minus-first diffraction order from the other aperture. Laboratory experiments confirm the predicted achromatic performance. 相似文献
19.
The coherence of the spectral broadening process is the key requisite for the application of supercontinua in frequency combs. We investigate the coherence of two subsequent supercontinuum pulses created in a photonic crystal fiber pumped by a femtosecond laser. We measure Young interference fringes from a Michelson-type interferometer at different wavelengths of the output spectrum and analyze their dependence on pump intensity and polarization. The visibility of these fringes is a direct measure of the coherence of the spectral broadening processes. 相似文献
20.
Ghost interference with partially coherent radiation 总被引:3,自引:0,他引:3
Ghost interference with partially coherent radiation sources is studied using optical coherence theory. The visibility of the ghost interference fringes is strongly influenced by the transverse size and transverse coherence width of the source. An increase of the transverse source size leads to a decrease of the fringes' visibility. An increase of the transverse coherence results in an increase of the visibility. The difference between ghost interference formed with entangled photon pairs and with partially coherent light is discussed. 相似文献