波导多层光存储读出光学系统的实验研究

波导多层光存储技术是光存储领域的前沿课题,它的读出光学系统是其核心和关键技术之一.基于波导多层光存储的原理,对其读出照明光学系统进行实验研究,提出了一种适用于波导多层存储的读出光学系统结构,对该技术的进一步研究及实用化有重要的参考价值.     

波导多层光存储读出照明光学系统的设计及实验研究

波导多层存储技术是光存储领域的前沿课题,它的读出照明光学系统是其核心和关键技术之一。从几何光学的角度对其读出照明光学系统进行设计,并进行实验研究和理论分析。     

波导多层光盘读出系统二维力矩器Ansys分析

波导多层光存储技术是光存储领域的前沿课题。针对设计要求计算出所要设计的二维力矩器的各项参数,在计算机中建立相应的模型,通过编程模拟出该二维力矩器的受力情况及计算出各阶频率。其一阶共振频率对实际运用是非常重要的参数之一,通过有限元分析软件Ansys的运用,得出该二维力矩器的伯德图,在图上查出聚焦及循迹方向一阶固有频率对应的值,与行业标准(草案)进行比对,验证该二维力矩器的参数设定是符合标准的。     

波导多层光盘调焦系统仿真研究与实验分析

针对多层光盘的特点,对多层光盘的调焦系统采用了斜入射方案,保证了各层信号分离和信号强度的要求,并利用MATLAB仿真了调焦结果,搭建了相关光路,通过采集调焦信号验证了仿真结果,而且可以发现,信号强度完全可以满足采集要求.     

波导多层存储中调焦方法的研究

光存储中调焦技术是其中最关键的技术之一.主要介绍了波导多层存储中的调焦方法的选择以及应用,在以前已经使用的像散法的基础上提出了斜入射调焦方法,并对该方法进行了理论上的分析计算机仿真,并得到了初步的实验结果.     

平板波导凹面衍射光栅设计方法研究

提出了一种平板波导凹面衍射光栅的设计方法,即改进的刻槽位置递推计算方法。该方法是对原有刻槽位置递推计算方法的改进,利用该改进方法可实现平板波导凹面衍射光栅的精确设计,特别是一些特殊光栅结构的设计。光栅的刻槽位置可通过一组约束方程表示,利用递推方法可求得约束方程的数值解。为提高计算精度,在方程组的数值求解过程中引入牛顿迭代算法。设计了两种特殊的光栅结构,即平接收场结构和平顶频谱响应结构,模拟结果证明了采用该方法进行设计的必要性和有效性。     

光波导功分器的短缩优化设计方法研究

提出并验证了一种针对光波导功分器短缩化的新的设计方法。在BPM软件仿真运行的基础上,归纳了单位圆心角弯曲损耗与曲率半径之间关系的仿真实验公式,建立了光波导功分器各级Y分支之间的单调弧形连接模型,确定了光波导分路器的长度、总的弯曲损耗、单口弯曲损耗以及均匀性的计算公式。综合考虑光波导功分器各参数间关系,采用了遗传算法全局优化技术,设计了合理可行的评价函数。通过对1×8石英光波导功分器的验证表明,与现行同类产品相比,插入损耗和均匀性指标持平,有效长度缩短了3.5mm以上。     

波导法兰钻孔模优化设计研究

在雷达产品中,波导组件通过波导法兰盘端面的孔系进行定位连接,孔位置偏差大小直接影响波导组件装配后波导口之间的重合度。波导组件装配精度高,雷达传输系统的功率损耗小,产品电性能好。因此,优化波导法兰盘钻孔模的结构,提高法兰盘钻孔精度显得尤为重要。     

波导类产品高效测量方法研究

针对波导类产品品种多、批量小、空间三维尺寸精度要求高以及测量效率低等问题,提出波导类产品空间三维尺寸测量的新方案。通过模拟波导类产品实际装配状态的方式,一次性测量波导法兰面之间X、Y、Z这3个维度的空间尺寸,并通过系列实验验证了该方法的高效性和测量准确性,在测量效率上远超传统的测量方法,可以广泛应用于不同接口和不同形状的波导类产品,具有推广应用的价值。     

波导隔离器加工工艺研究

本文介绍雷达馈线关键零件波导隔离器焊接成形工艺方法。通过对波导隔离器焊接工艺定位结构设计保证其定位装配尺寸和位置精度,并且在第二次钎焊中使用柔性夹具减小了水冷管道焊接变形,成功实现了在普通钎焊炉中波导隔离器的焊接成形。     

Parallel heterodyne readout of information from three-dimensional superimposed holograms

A method is proposed for parallel (simultaneous) readout of information from threedimensional “coupled” Fourier holograms. The method is based on the principle of transformation of informational degrees of freedom of the optical signal with the use of moving diffraction gratings: the spectrum of spatial harmonics of superimposed holograms is transformed to a spectrum of time harmonics separated in terms of frequency. A method of formation of images of moving gratings with a prescribed orientation in the volume of the recording material is developed. Conditions of the frequency separation of the signals, resolution of the method over the material depth, and the number of detected bits as a function of grating parameters are obtained.     

A multiresonance method for measuring the reflection coefficient in a waveguide

A new method for measuring the complex reflection coefficient in rectangular waveguides using a scalar network analyzer is proposed. This method is based on measurements of the resonance characteristics of a quasi-resonator, i.e., a portion of the waveguide between a reflecting object on one side and an object with a known scattering matrix on the other side. One advantage of the multiresonance technique is that simultaneous analysis is performed for the entire set of resonance frequencies, which substantially increases the accuracy in finding the reflection coefficient. The errors in measuring the magnitude and phase of the reflection coefficient in actual experiments were close to 0.015 and 1.5°, respectively.Translated from Pribory i Tekhnika Eksperimenta, No. 1, 2005, pp. 94–100.Original Russian Text Copyright © 2004 by Ponomarenko, Popov.     

A study of the switching of the microwave compressor switch in a circular waveguide

Results of the experimental study of the interference switch for the H ₁₁ mode in a circular 10-cm-wavelength waveguide are presented. The conditions required for efficient microwave discharge switching of the interference switch are determined. The results of the study of the switching process allowed us to design and produce an interference switch with better characteristics than those of rectangular waveguides. It is shown that this switch extracts the stored energy from the microwave compressor cavity more efficiently and improves the amplitude stability of the output pulse radiation.     

Suppression of a sound field in a wide circular waveguide using an active method

An active process of noise suppression in a wide waveguide with the help of a receiving-emitting device located on the waveguide wall is studied. Using the measurement results of an extraneous field propagating in the waveguide, the amplitudes and phases of auxiliary emitters for suppression of the incident exterior field are determined.     

A waveguide method for the investigation of the elastic wave action on a newly formed crack

A technique for studying the processes of mechanical action on a newly formed crack and a device with a movable waveguide used to form fixed cracks in a rock sample in laboratory conditions are described. Analyzing the features of acoustic pulses, one can relate them to the dimensions and rate of the crack propagation, as well as control the sample destruction process. Characteristic time intervals in the sample destruction process are observed and resolved. Experimental results on the destruction of a marble plate with the use of the waveguide method are presented.     

The effect of regular differences in a cross section on the testability of a rod tested by the acoustic waveguide method

The mechanism of acoustic noise generation in a rod with regular differences in the cross section is studied theoretically and experimentally. The effects of the rod’s geometry and the basic control parameters on the testability of the rod tested by the acoustic waveguide method are evaluated. Recommendations for improvement of the rod’s testability are made.     

磨削粗糙度在线检测方法的实验研究

本文对基于摩擦声发射信号的磨削粗糙度在线检测方法进行了实验研究。实验结果表明，采用声发射传感器探头与磨削表面摩擦产生的声发射信号的特征可以对磨削表面粗糙度进行评价，建立了摩擦声发射信号特征与磨削表面粗糙度之间的对应关系，并通过实验对该方法的可行性进行了实测。结果表明，探针与工件表面摩擦声发射信号的FFT和RMS特征与磨削粗糙度有很好的对应关系，可用于磨削表面粗糙度的在线检测。