Method for Birefringence Measurements with Correction of Errors Due to Multiple Reflection in Anisotropic Plates

Abstract

Birefringence measurements of anisotropic plates using coherent light are affected by errors due to the multiple reflections in the investigated plate. An evaluation method for measuring birefringence is presented, where the intensity distributions of two light beams are used for the correction of these errors. These beams arise from a polarizing beam splitter, which is the analyser of the polarization system. In this paper, a theoretical treatment is given which shows that this method results in more accurate values than the usual methods, especially for highly refractive materials with a small birefringence.     

Sample Size Determination for Tolerance Limits

The problem of determining sample size to take for a tolerance limit L(X), where L(X) is a function of a random sample X ₁, …, X_n from a distribution with density f(x : θ), and

is investigated. A criteriorl of “goodness” of tolerance limits is developed and a method given, using this criterion, for solving the sample size problem. Examples are given using the uniform, exponential, and normal distributions as underlying models.     

Note on Tolerance Limits for a Binomial Distribution

A method is given for using a confidence interval on the parameter p of a binomial distribution to obtain a tolerance interval on the distribution. An example is given to illustrate the setting in which tolerance limits for a binomial distribution might be useful, and to demonstrate that the calculations are relatively easy with a good set of binomial tables.     

An Approximation to Two-Sided Tolerance Limits for Normal Populations

The authors present a means of computing two-sided tolerance limits for normal populations by algebraic formulae. Their method utilizes the Fisher-Cornish approximation to the chi-square quantile and an equation in three coefficients empirically derived. They include an analysis of the errors in the two formulae and suggest methods of incorporating the calculations in computer programs.

The tables of Weissberg and Beatty [6] have been an invaluable aid for the construction of two-sided tolerance limits for normal populations. In this article we present a means of computing these tolerance limits with a high speed computer following the lead of Weissberg and Beatty. Our method avoids the problem of solving integral equations by replacing the integral equations with algebraic formulae which approximate the solution to a reasonable degree of accuracy.     

Tolerance Limits Based on Range and Mean Range

Owen (1964) has developed tolerance limits based on the sample mean, x, and the sample standard deviation, s, which control percentages in each tail of the normal distribution. In this paper tolerance limits based on x and the range R or the mean range R_g,r are developed. Tables of factors for the tolerance limits are given.     

New Methods for One-Sided Tolerance Limits for a One-Way Balanced Random-Effects ANOVA Model

The problem of determining one-sided tolerance limits or, equivalently, one-sided confidence limits on a quantile of a normal population with variance σ² = σ² _b + σ² _b is considered in this article. The tolerance limits are obtained using data from a one-way balanced randomeffects sample from this population. Two procedures are introduced—a simple approximate method based on an asymptotic expansion and a computer-intensive procedure that provides very nearly the nominal confidence in the presence of the nuisance variance-component ratio. For the computer-intensive procedure, tables are provided that eliminate the need for most of the computation for some important situations. Tolerance limits for strength are routinely used in structural design. Material strength, particularly for composite materials, often exhibits considerable between-batch variability. A tolerance limit that provides nearly the nominal confidence is usually preferable to a conservative limit, since a conservative tolerance limit underestimates the capability of the material. An aircraft-industry application to determining tolerance limits for composite material properties in the presence of between-batch variability is discussed.     

Evaluation of Errors in Calibration Procedures for Measurements of Reflection Coefficient

Procedures for the calibration of computer-controlled network analyzers in reflection measurements are studied. The major aim of this paper is to develop an error analysis in order to define a quality factor, for evaluating the performances of a calibration procedure. This is done by using the invariance property of the cross ratio, which easily lets one obtain analytical expressions for the residual errors As an application of this technique, a comparison between two actual calibration procedures has been made using an automatic network analyzer. The experimental results favorably compare with the ones obtained on theoretical basis.     

A Graphical Method for Calculating Reflection Errors in Radiation Thermometry

This article presents a graphical method to calculate reflection corrections for radiation thermometry. The method is based on the observation that the measured radiance of a target is a linear combination of radiances dependent on the emissivity of the target. The method is most easily implemented as a nomogram, enabling thermometer users to estimate reflection corrections immediately when measurements are taken. The nomogram also provides a visual means of explaining the impact of reflection errors on measurements and for explaining the impact of measurement uncertainties on temperature measurements corrected for reflections.     

Sample Size For Tolerance Limits on a Normal Distribution

Sample size tables are given for tolerance limits on a normal distribution. Wald-Wolfowitz two-sided limits and one-sided limits are considered. The criterion used for determining sample size is as follows: For a tolerance limit such that Pr (coverage ≥ P) = γ, choose P′ > P and δ (small) and require Pr (coverage ≥ P′) ≤ δ. Five levels of P, three levels of γ, three levels of P′, and three levels of δ are used in the tables. The tables are given for the common case where the degrees of freedom for the x² is one less than the sample size, but it is shown how to use the tables for other cases which occur in simple linear regression and some experimental designs. Examples are given to illustrate the use of the tables.     

平板新老规程对比

文章对新旧规程进行了对比,并对修订更改印刷错误之处进行了说明。     

Standard Errors for the Eigenvalues in Second-Order Response Surface Models

In the interpretation of the geometry of second-order response surface models, standard errors and confidence intervals for the eigenvalues of the second-order coefficient matrix play an important role. In this article, we propose a new method for estimating the standard errors, and hence approximate confidence intervals, of these eigenvalues. The method is simple in both concept and execution. It involves the refitting of a full quadratic model after rotating the coordinate system to coincide with the canonical axes. The estimated standard errors of the pure quadratic terms from this refitting are then used as approximate standard errors of the eigenvalues. Because this approach is based on the canonical form, it is geometrically intuitive and easily taught. Our method is intended as a way for practitioners to get quick estimates of the standard errors of the eigenvalues. In our justification of the approach, we show that it is equivalent to using the delta method proposed by Carter, Chinchilli, and Campbell.     

板材表面质量在线检测方法概述

板材表面的质量决定了板材的使用性能、寿命、工作可靠性等一系列重要参数,因而在工程上,对于影响板材表面质量的因素以及针对板材表面质量的检测方式也越来越受重视。文中分别介绍和分析了板材常见的几种缺陷形式、板材表面质量对其使用性能的影响,并以高精度钢板为例介绍表面缺陷的传统无损检测技术、激光扫描和机器视觉技术;最后,通过各种检测方式的结果对比得出结论。     

Surface Contouring of Reflecting Plates Using Intensity Integration Technique

Abstract: An intensity-based image processing method termed the Intensity Integration Technique (IIT) is proposed to obtain the slope and curvature of loaded reflecting plates. It employs divergent beam illumination to cover a large plate area. The deformation field is established by applying cumulative (integrated) intensity as the correlation parameter to relate the reflected images from the undeformed and deformed states of the object. The method is suited to modern computing environment and requires a simple experimental set-up. It obtains absolute values of slope and curvature.     

Simple Estimates for the Effects of Mid-spatial-Frequency Surface Errors on Image Quality

Mid-spatial-frequency surface errors can be introduced by various manufacturing processes. These errors bridge the gap between traditional figure and finish errors. Although the effects of mid-spatial-frequency errors on the imagery of an optical system can be modeled with a ray-based approach, simply tracing rays provides little insight. We present an alternative method that treats surface errors as perturbations to the nominal surface profile. This approach, combined with standard statistical methods, allows one to make simple back-of-the-envelope predictions of the effects of mid-spatial-frequency errors for various measures of optical performance. Two examples illustrating the effectiveness of this approach are presented.     

表面等离子体波衰减全反射谱的非扫描测定

提出了一种利用ＣＣＤ摄象技术对表面等离子体波衰减全反射（ＡＴＲ峰）进行一次成象测量的方法。利用光学图象空间滤波技术对激光光斑进行均匀化处理,并利用计算机图象处理技术对ＣＣＤ取图象进行噪声信号的易除和图象信号的优化,以及高斯分布激光光强的反高斯变换技术, 实现了ＡＴＲ峰的非扫措测量,避免了传统的利用步进马达驱动θ／２θ转角仪测量ＡＴＲ峰的繁琐过程。     

用公差原则对光滑极限量规的分析与研究

本文列举了不同的公差原则。指出了形位公差和尺寸公差是可以相互转换和补偿的,着重是用公差原则对光滑极限量规的分析与研究,便于公差原则的统一认识。     

基于双响应面法的公差设计研究

探讨了产品综合成本的构成,以此为基础提出了以产品综合成本最低为目标的公差稳健设计模型,并利用双响应面法(Response Surface Methodology ,RSM) 来实现公差的稳健优化设计。