散斑和云纹的编码、解码防伪技术

提出了“编码散斑隐型密码”、“Ｍｏｉｒｅ条纹显型密码”、“编码Ｍｏｉｒｅ条纹隐型密码”的概念和具有极高技术含量的实用防伪技术,直接用于商品包装防伪,亦可与全息防伪、荧光防伪、热敏防伪等相结合,提高现行防伪技术的综合防伪性能。该技术解码过程简单,极具实用价值。     

论莫尔条纹的计算

指出了当前莫尔条纹计算式所存在的问题,提出了正确的节距、夹角计算公式.     

基于圆光栅莫尔条纹的CGH元件对准

在双计算全息（CGH）检测非球面的方法中,两片CGH元件位置的精确对准是确保高精度测量的必要前提,针对一凸双曲面检测系统,提出了在主CGH的外围刻制四组圆光栅付的方法来实现该系统中CGH元件的精确对准,其原理基于两个栅线频率相近的同心圆光栅重叠能产生莫尔条纹,通过观察条纹的变化来判断两光栅（一组光栅付）的相对偏移,各组光栅付若同时达到同心,两元件亦便对准。通过对圆光栅进行建模,分析了莫尔条纹产生的原理,仿真模拟了Ф5mm口径内分别包含49个和50个同心圆（周期50μn）的两圆光栅在不同偏移时的条纹图,且实际制作了这样的两个圆光栅,并采集了两光栅重叠后的条纹图,其结果表明,眼睛很容易分辨出1／20周期即2．5μm的偏移。     

Reverse engineering: high speed digitization of free-form surfaces by phase-shifting grating projection moiré topography

A new digitization method is presented for automatic acquisition of geometric information on free-form surfaces for the sake of reverse engineering. Principles of grating projection moiré topography are utilized with emphasis on enhancing the measuring resolution by incorporating phase-shifting fringe analysis. The measuring range and resolution can be readily adjusted to suit the object size to be measured, simply by varying the spatial line pitch of the moiré gratings. In addition, no time-consuming beam scanning is required in the measurement, keeping the measuring time relatively low as compared with other existing techniques. Experimental results demonstrate that the three-dimensional coordinate data of 640×480 points can be attained within 5 seconds run on an IBM PC 586, with measuring resolutions of 0.1 mm down to 0.001 mm.     

用视频显微镜实现显微干涉计量的实验研究

采用视频显微镜作为显微成像和电子记录的工具进行显微干涉计量,光路简洁,调整方便.用显微云纹干涉系统和显微散斑干涉系统分别测量了物体的面内变形、离面位移和物体的形状.实验结果表明视频显微镜可应用于各种显微干涉计量场合.     

INTRAGRANULAR VC AND M_(23)C_6 IN GH36 SUPERALLOY

The distinct images of intragranular VC were observed on TEM in superalloy GH36underwent normal heat treatment and prolonged aging.The size of VC particles were meas-ured by means of Moire pattern,and the misfit between VC and austenite was also calculated.The M23C6 enveloped in VC shell was also observed in the prolonged-aged specimens.Thecoherent relation between intragranular M_(23)C_6 twins and austenite as well as its coherent in-terface were also studied.