Principle Of Interference Research Articles

¿Requiere la interferencia de la superposición de ondas como principio físico?

La superposición de ondas es una de las ideas fundamentales más preciadas de la física. Durante cerca de dos siglos ha constituido el principio físico de la interferencia y la difracción de las ondas y, a lo largo de los últimos cien años se ha empleado como instrumento predictivo del comportamiento de sistemas cuánticos. Sin embargo, dicha superposición no puede explicar la interferencia de las ondas y de las partículas de manera generalizada debido, principalmente, a la diferente interpretación de la función de onda en cada contexto. Dado que los fenómenos del mismo tipo deben obedecer al mismo principio, o ser consecuencia de las mismas causas, esta limitación de la superposición de ondas es, por lo tanto, un problema actual en los fundamentos de la física. Como solución se propone un nuevo principio físico, el cual proporciona la misma explicación para la interferencia de las ondas y de las partículas sin detrimento de la precisión predictiva. Su validez se apoya en el análisis de resultados experimentales reportados por otros autores. Este principio es completamente novedoso y conduce a una formulación no estandarizada de la interferencia, que deberá abrir nuevos campos de discusión sobre este tema fundamental de la física. © 2017. Acad. Colomb. Cienc. Ex. Fis. Nat.

All-Optical Half-Adder Circuit Based on Beam Interference Principle of Photonic Crystal

AbstractNow a day’s photonic crystals (PhCs) are in trends for designing of various integrated circuits like combinational and sequential circuits. The designing of all-optical half adder circuit based on beam interference principle, using T-shaped square lattice with silica dielectric rods in air background, is proposed. This design is a combination of two structures: one part of it works as AND gate and other part works as XOR gate. This structure is simulated using finite difference time domain (FDTD) method and verified numerically using PWE band solver and also using MATLAB.

Active force control of structure-borne sound based on robust optimization subjected to an irregular cavity with uncertainties

This paper proposes a novel method of structure-borne sound analysis and active force control, which combines interval mathematics and robust optimization theorems, to achieve vibration damping and noise reduction for enclosed cavity systems with bounded uncertainty. By introducing the interference principle of sound wave, responses under control can be obtained by solving finite element equations of structural–acoustic coupling systems. Through synthetical considerations of parameter dispersion in practice, the interval quantitative model, which only needs limited sample data, is defined, and the interval Taylor extension approach is employed to further determine boundary rules of responses of structural vibration and acoustic noise. On this basis, a new interval-oriented robust optimization framework is established to seek the optimal secondary force to simultaneously minimize nominal and radius levels of sound pressure indexes at concerned space and frequency domains. A complicated engineering example of the 3-D bomb cavity is eventually presented, in which numerical and experimental results can demonstrate the usage, validity and effectiveness of the developed methodology.

Interfacial delamination in glass-fiber/polymer-foam-core sandwich composites using singlemode–multimode–singlemode optical fiber sensors: Identification based on experimental investigation

Identification of interfacial delamination in the glass fiber/polymer-foam-core sandwich composites is difficult if the delamination does not propagate to the side surface of the specimen. However, these damages may eventually lead to compromising the sandwich composite structural component. A cost-effective novel embedded fiber optic sensor is being proposed in this manuscript, which works on the principle of multimode interference, to perform distributed sensing of interfacial delamination within the sandwich composites while in service. Even though this easy to use methodology has been used to identify interfacial delamination, this methodology can also be used for different other types of interfacial/interlaminar distributed strain sensing of samples under mechanical as well as thermal loads.

Chirped fiber tip Fabry-Perot interferometer.

We demonstrate a novel fiber tip Fabry-Perot (FP) interferometer with a chirped spectral characteristic. The FP interferometer is formed by an etched chirped fiber Bragg grating (FBG) and the fiber tip broadband end-face mirror, and the etched chirped FBG is prepared by a dynamic chemical etching process, shaping the taper and reducing the size from 125μm to just a few micrometers. Due to the spectral characteristic of the etched chirped FBG, the different resonance wavelengths correspond to different gating positions which give rise to the gradient cavity length in the chirped fiber tip FP interferometer; thus, this FP interferometer possesses a chirped interference spectrum. Subsequently, the FP interferometer is fabricated, and the temperature response is investigated by measuring the wavelength shift of the resonance dips in the reflection spectrum. Significantly, because of its special interference principle and configuration, we experimentally demonstrate that this FP interferometer can be used for the spatial localization of the external temperature perturbations.

Three-degree-of-freedom common-path laser measurement system

Common optical path arrangement was adopted to design a three-degree-of-freedom laser measurement system for measuring 1D displacement and 2D angles of a moving stage simultaneously on the basis of the principles of Michelson interference and laser auto-collimation. In the displacement measurement, the fine resolution of displacement measurement was achieved by using optical path difference doubling technique. Combined with polarization interference technology and signal differential processing, high-quality displacement output signal was obtained. In the angle measurement, changes in yaw and pitch of a moving stage caused the position change of the mirror which was mounted on the stage. The incident beam was reflected by the mirror and detected by a four-quadrant detector. According to the position change of the spot, yaw and pitch angles were obtained. The stability, resolution tests and the comparison experiments with the British Renishaw XL-80 laser interferometer were done. Experimental results show that the system has the resolution of 0.8 nm for displacement measurement and 0.2″ for angle measurement. Compared with the results of Renishaw XL-80 laser interferometer, the maximum deviation of displacement is less than 100 nm within the measurement range of 50 mm. The maximum deviations of yaw and pitch are 0.5″ and 0.4″.

Design of All-optical Half-subtractor Circuit Device using 2-D Principle of Photonic Crystal Waveguides

Abstract A design of all-optical half-subtractor (AOHS) is presented based on two-dimensional (2-D) photonic crystal (PhC) waveguides without using optical amplifiers and nonlinear materials. It is an essential component of various photonic integrated circuits. The design of AOHS circuit is based on beam interference principle, using square lattice of Y-shaped and T-shaped waveguides with silicon dielectric rods in air substrate. It is validated through finite-difference time-domain and using MATLAB simulations.

Sensitivity-enhanced single-mode fiber-tapered hollow core fiber-single-mode fiber Mach–Zehnder interferometer for refractive index measurements

ABSTRACTIn this paper, a sensitive-enhanced single-mode fiber—tapered hollow core fiber—single-mode fiber Mach–Zehnder interferometer is demonstrated for refractive index sensing. The sensitivity was improved by forming an up-taper at the two splicing joints and concave cone in hollow core fiber. The up-tapered regions served as a more effective mode splitter/combiner, and the tapered hollow core fiber was used to generate a stronger evanescent field to enhance the interaction of light with the analyte. According to the principles of interference between the cladding and fundamental modes, we performed refractive index measurements. The experiments indicated that the proposed sensor has a high refractive index sensitivity of 214.97 nm/RIU in the refractive index range of 1.333–1.379, with a minimum refractive index measurement resolution of 9.3 × 10−5. In addition, the sensor had a low temperature response of 2.96 pm/°C in the range from 50 to 85°C and a low cross sensitivity of 1.377 × 10−5 RIU/°C. The proposed sensor is attractive for its high refractive index sensitivity, easy fabrication, low cross sensitivity, and good mechanical strength, making it of potential value for refractive index measurements for chemical and biological sensing.

Influence of thermal-vacuum environment on the recovered spectrum of spatial heterodyne spectrometer

Thermal-vacuum environment adaptability is one of the key performances of space optical instruments, especially for hyper-spectral instrument, and spatial heterodyne spectrometer (SHS) should provide high spectral stability for the detection of atmosphere CO2. Based on the research of the spatial heterodyne interference principle, simulation test in thermal-vacuum environment and quantitative analyses are carried out. The relationship among environment changes and the divergence half-angle of collimating lens, Littrow wavelength of field widened interferometer, different defocusing amount and pantograph ratio of imaging lens are analyzed. In order to verify the theoretical analysis, thermal-vacuum experiment is performed. The results show that the spectral deviation and profile are matched with theoretical analysis, and spectral stability is less than ±0.01 nm under the temperature from 19 ℃ to 21.2 ℃ by the substrates made of fused Silica (Corning 7980 0F). Quantitative analyses provide theoretical basis for the thermal control requirement and Littrow wavelength selection in normal atmospheric pressure.

Structural colors of fabric from Ag/TiO2 composite films prepared by magnetron sputtering deposition

PurposeStructural color is more brilliant in color, more resistant to sunshine and will not fade away with time, and more environmental friendly than traditional dyes and pigments. The purpose of this paper is to prepare structural colors of fabrics coated with Ag/TiO2 composite films by magnetron sputtering, and analyze the relationship between the colors and the thicknesses of TiO2 films in Ag/TiO2 composite films.Design/methodology/approachPreparation of Ag/TiO2 composite films by magnetron sputtering and their deposition on textiles were investigated. The chemical compositions and surface morphology of Ag/TiO2 composite films were examined by X-ray photoelectron spectroscopy and scanning electron microscopy, and the structural color of fabric coated with Ag/TiO2 composite film was also analyzed.FindingsAg/TiO2 composite films deposited on textile substrate exhibited structural colors, and the bright colors could be adjusted and controlled by the thickness of TiO2 thin films in Ag/TiO2 composite films without any dyes or pigments. By comparing the results of theoretical calculation and experimental results, it was found that the creation of structural colors by the experiment was coincident to the colors by theoretical calculation according to the film interference principle. There was a linear relationship between the thickness of TiO2 film and the wavelength of the structural color.Originality/valueCompared to traditional coloration by dyes or pigments, the coloration of textile by structural color from Ag/TiO2 composite films prepared by magnetron sputtering was very environmental friendly and simple without water consuming, time consuming and tedious work. Structural colors have great potential applications in textiles in place of traditional dyes and pigments. Furthermore, the textiles coated with Ag/TiO2 composite films have good electrical, optical and magnetic properties, and can be used in apparel, home furnishings and industrial fabrics.

Direction-tunable enhanced emission from a subwavelength metallic double-nanoslit structure.

Controlling light emission out of subwavelength nanoslit/aperture structures is of great important for highly integrated photonic circuits. Here we propose a new method to achieve direction-tunable emission based on a compact metallic microcavity with double nanoslit. Our method combines the principles of Young's interference and surface plasmon polaritons interference. We show that the direction of the far-field beam can be controlled over a wide range of angles by manipulating the frequency and relative phase of light arriving at the two slits, which holds promise for applications in the ultracompact optoelectronic devices.

A novel vibration sensor based on phase grating interferometry

Vibration sensors with high accuracy and reliability are needed urgently for vibration measurement. In this paper a vibration sensor with nanometer resolution is developed. This sensor is based on the principle of phase grating interference for displacement measurement and spatial polarization phase-shift interference technology, and photoelectric counting and A/D signal subdivision are adopted for vibration data output. A vibration measurement system consisting of vibration actuator and displacement adjusting device has been designed to test the vibration sensor. The high resolution and high reliability of the sensor are verified through a series of comparison experiments with Doppler interferometer.

Optical coefficients extraction from terahertz time-domain transmission spectra based on multibeam interference principle

We demonstrated a data-processing method based on multiple beam interference and Fresnel equations that simultaneously gave the refraction index and absorption coefficient from the raw data of terahertz (THz) time-domain spectroscopy (TDS), which laid the foundation for obtaining the dielectric parameters. This method was independent of phase processing, and complete material information was reserved without having to cut the time-domain signal. The optical coefficients including refractive indices and absorption coefficients of white polyethylene and quartz samples at different thicknesses were obtained. The applicability and accuracy of this method were discussed and verified by comparison with the traditional data-processing method of THz TDS.

Transparent Long-Pass Filter with Short-Wavelength Scattering Based on Morpho Butterfly Nanostructures

We combine the principles of moth-eye antireflection, Bragg scattering, and thin-film interference to design and fabricate a short-wavelength scattering/long-pass filter with sharp cutoff, high transmission of infrared light, and strong reflection of visible light into high angles. Based on the lamellae-edge features on Morpho didius butterfly wings, nanostructures are self-assembled via sequential one-chamber chemical vapor deposition, metal nanoparticle formation, and wet-chemical etching. Finite-element modeling demonstrates strong (>45%) reflection into the first diffracted order for short wavelengths, while retaining >80% transmission for longer wavelengths. Fabricated nanostructures couple more than 50% of reflected light into angles of >10° while enabling broadband long-pass transmission. Such structures have potential applications in light trapping for tandem solar cells, stealth, and signals processing.

Silhouette-free image encryption using interference in the multiple-parameter fractional Fourier transform domain.

A novel approach for silhouette-free image encryption based on interference is proposed using discrete multiple-parameter fractional Fourier transform (DMPFrFT), which generalizes from fractional Fourier transform. An original image is firstly applied by chaotic pixel scrambling (CPS) and then encoded into the real part of a complex signal. Using interference principle, the complex signal generates three phase-only masks in DMPFrFT domain. The silhouette of the original image cannot be extracted using one or two of the three phase-only masks. The parameters of both CPS and DMPFrFT can also serve as encryption keys to extend the key space, which further enhance the level of cryptosystem security. Numerical simulations are demonstrated to show the feasibility and validity of this approach.

Structural colour of polyester fabric coated with Ag/TiO2 multilayer films

Silver/titanium dioxide (Ag/TiO2) multilayer films with structural colours on polyester fabric were fabricated using direct current (DC) magnetron sputtering. The bright and variable structural colourations of polyester fabrics coated with an Ag/TiO2 film were investigated with GretagMacbeth Color-Eye 7000A spectrophotometer. The compositions, surface morphologies and microstructure of multilayer films deposited on polyester fabrics were also analysed by X-ray photoelectron spectroscopy, Scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results indicated that the structural colours varied with the thickness of TiO2 thin layer in Ag/TiO2 multilayer films. The TiO2 thin layer thicknesses were 42, 65.6, 82, 98.4 and 114.8 nm, and the samples colours became purple, light blue, blue, pink and dark red, respectively. The creation of colours was coincident to film interference principle. XRD analysis revealed that there were four diffraction peaks for Ag/TiO2 multilayer film at 38, 44, 64 and 77° of 2θ, corresponding to (110), (200), (220) and (311) Ag crystal planes and that TiO2 structure in Ag/TiO2 multilayer film was non-crystalline.

Nonlinearity error in homodyne interferometer caused by multi-order Doppler frequency shift ghost reflections.

This paper reports a hitherto undiscovered cyclic error whose origin is different from that of conventional errors in homodyne interferometers. To explain this error, a model based on ghost reflections and the interference principle is developed. In general, in homodyne interferometers, multi-order Doppler frequency shift ghost beams participate in the final interference and generate multi-order cyclic errors. This "new" cyclic error is compared with conventional errors by means of Lissajous curves. And we establish a setup to validate our proposed model. We use a corner cube retroreflector to replace the mirror and we find the error is significantly reduced. We believe that our findings can contribute to the further development of highly accurate homodyne interferometers.

Research on NC Grinding Tooth Surface Morphology of Spiral Bevel Gear

Based on the analysis of expanding cup wheel topography, grinding wheel model, whose grain diameter and space position on the wheel surface are distributed randomly, is established and used to simulate grinding tooth surface topography. Based on the analysis of the formation mechanism of grinding tooth surface topography, the relative movement relationships between grinding wheel and tooth surface, and the interference and superimposition principle of grain tracks, the modeling and simulation of grinding tooth surface morphology of spiral bevel gear are made. The simulation morphology of grinding tooth surface of spiral bevel gear is obtained by Matlab software. By the comparative study on experiment, The results show that the simulation morphology and experimental observing one is basically identical. These indicate that the topography simulation model of grinding tooth surface of spiral bevel gear established in this paper is more accurate and reasonable.

Analysis of the Test Method of Quartz Glass Optical Homogeneity

The optical quartz glass is widely applied in optical system , photo communications，inertial navigation，etc.It must have high optical homogeneity. Optical homogeneity of the optical quartz glass directly affects the wavefront quality of the optical transmission system, and changes the wavefront aberration of the system. How to accurately determine the optical homogeneity of the quartz glass is especially important. Currently，the method of test for optical homogeneity mainly used by interference principle. This paper analyzes various existing interference measurement method and test equipment. Summarized the advantages and disadvantages of various test methods，using range and measurement accuracy.

多光束干涉及其GUI设计

本论文详细研究法布里–珀罗多光束干涉和多棱锥产生的多光束干涉，分析探讨了干涉原理和条件、干涉条纹特征以及影响条纹精细度因素。得到了多光束干涉的规律，即平行平面薄膜产生的多光束干涉条纹十分细锐明亮，并且反射率越大，产生的干涉条纹越明亮细锐。此外，增大介质折射率或者增大夹层厚度和介质薄膜厚度，在一定区域内所观察到的干涉条纹数则越多。多棱锥干涉产生的空间多光束干涉图案是沿光束传播方向没有变化的二维周期性图案，并且随着棱数的增加，干涉场将会变为同心圆结构的贝塞尔光束的场分布。应用MATLAB软件对迈克尔逊干涉、法布里–珀罗干涉以及多棱锥多光束干涉设计了GUI界面，形象生动地表征了相关参数变化引起的干涉条纹的变化，且与理论相吻合的结果。 In this paper, the Fabry-Perot interference and multi-beam interference produced by multi-pyramid are studied in detail. The principle and condition of interference, the characteristics of interference fringes and the factors affecting fringe fineness are analyzed and discussed. The law of multi-beam interference is obtained, that is, the multi-beam interference fringes which produced by parallel plane films are very sharp, and as the reflectivity increases, the interference fringes become brighter and thinner. In addition, with increasing the refractive index of the medium or the thickness of the interlayer and the dielectric film, the number of interference fringes observed in a certain area will be increased. The spatial multi-beam interference pattern produced by multi-pyramid interference is a two-dimensional periodic pattern with no change in the direction of beam propagation, and with increasing the number of edges of pyramid, there is a series of changes in the interference field. When the number of edges of pyramid increases to a sufficient edge, the interference field distribution will become concentric structure of the Bessel beam field. The software of MATLAB is used to design GUI interface of the Michelson interference, Fabry-Perot interference and multi-pyramid multi-beam interference, which vividly depicts the change of the interference fringes caused by the change of the relevant parameters and is consistent with the theory.