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A new method for registering stereograms where orientated interference fringes provide the desired directivity for horizontal parallax is presented. With the help of a strip shaped mask behind the ground glass, the stereograms obtained by this newly developed method produce a rainbow effect. In addition to having a wide angle of view, these stereo images can also be observed under an extended white light source. In addition, the plane hologram characteristics of the stereo images obtained by this method indicates that the image size will not scale with the variations of the reconstructing light source. A quantitative analysis on the distortion problems related to this method is discussed. The distortion-free conditions for making a holographic stereogram was developed using this theoretical analysis. A sensitivity analysis related to the viewing position errors for images recorded using this method is also presented.

In this paper a fuzzy model for fabricating planar-grating is given. In the model, the diffraction efficiency of the holographic grating (predicted by computer simulation) has a reasonable match with the experimentally verified results. The method can be summarized in three steps: first, a choice of the grating characteristics, which are closely related to the diffraction efficiency factors, is made; secondly, according to our experience, we construct the fuzzy matrix from the grating manufacturing parameters and the grating characteristics; finally, we use the fuzzy matrix composition to obtain the diffraction efficiency factors. Then, coupled wave theory is used to predict the diffraction efficiency. The comparisons between the results of this fuzzy model and experiments are given. It is found that the application of fuzzy set theory in grating manufacturing reduces the cost of the process and improves the quality of the grating.

This paper presents an optical technique for sphericity measurement of a ball by means of phase shift interferometry. The ball is placed in a fixture on a numerically control rotary stage to achieve a 360 degrees inspection. The eccentricity of the rotary stage's spindle is estimated in terms of Zernike polynomials. Experimental procedure, sphericity evaluation, and sphericity measurement results are presented.

The Hough transform is a powerful tool for machine vision systems. In this paper by using inexpensive LCITV instead of expensive SLM as an input device a commercializable optical Hough transform processor is presented. The integration of this processor with a digit image processing system is also discussed.

A random phase shift atgorithm based on the principLe of phase-measuring profiLometry with a projected sinusoidaL grating to 360 measurement-of the surface topography of 3-D diffuse objects is presented. In contrast to phase shifting interferometry this method eLiminates the needs of vibration isoLation thus an on-Line or in-process amasurement could be executed. 1.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A traditional MSF only possesses the discriminating ability of shift invariance of patterns when it is used for pattern recognition and can't recognize patterns with rotation. To overcome this problem, a target pattern was replaced by one of its circular harmonic components when we select the reference pattern, i.e., the MSF should be made from the conjugate of the Fourier spectrum of its circular harmonic components.

A digital phase shifting technique capable of quantitatively determining the phase of holographic interferometric displacement fringes is presented. This technique uses computer control to take data and calculate surface deformation. The phase value at each detector point can be calculated by taking four successive intensity data frames with the reference phase shifted between each frame. The displacement fringe order number can be assigned by adding or subtracting 2π from a data point until the phase difference between adjacent data points is less than π. Experimental results show that this technique can precisely determine a fraction of a fringe with an accuracy of ±1°.

An optical surface roughness measuring instrument has been developed which provides a noncontact method of obtaining surface characteristics of engineering surfaces. The system consists of a standard Twyman-Green interferometer controlled by a piezoelectric transducer, a linear array of photodiode detectors, and a microcomputer. The combination yields a system that measures the height variations of surfaces to a high degree of precision. Theoretical analysis and experimental systems are described. Surface roughness measurements are made in mirror, pre-coating surface, epoxy-painting surface, and fine-machined aluminium surface. Experimental results show that the measuring range of the sensitivity is from below 0.001 μm up to 2 μm rms. Due to the ability of high precision and fast measurement speed, an on-line metrological tool for roughness measurement of engineering surfaces can be developed.

A digital phase shifting technique capable of quantitatively determining the phase of holographic interferometric fringes is presented. This technique uses computer control to take data and to calculate phase. The phase value at each detector point can be calculated by taking four successive intensity data frames with the reference phase shifted between each frame. The amount of phase shift introduced by this technique is unimportant. Theoretical analysis and experimental systems are described. Experiments are made in beam deflection measurements, holographic nondestructive testing and surface contouring of diffuse object to show the versatile applications of this technique.

This paper proposes a holo-speckle interferometer with one single set -up, This is made possible by using two collimated reference beams, one at each state, in typical double exposure holographic interferometry. At reconstruction, if the same referencebeams are used to reconstruct the images, then the holographic interferometry is obtained,If we put a half -wave plate into the light path of one reference beam, i.e., the polariza-tion states of the two reference beams are orthogonal, then a speckle interferometry is obtained. In experimental mechanics, the holo -specklegram provides a means to separatelymeasure the in -plane and out -of -plane surface displacement components. In addition to this, it has some other advantages. The orthogonal polarization property of the two reference beams play a key role fordetermining the type of interferometry and the qualities of the hob and speckle grams,therefore, types of orthogonal polarization have been investigated and discussed.Introduction

A system combining the concept of polarized light and the techniques of laser interferometry & electronic circuits is proposed to measure the linear speed of moving solid and also recognize the kinematic direction simultaneously in this paper. The whole system is composed of the optical system and the signal processing system. The optical system suggests a modified Michelson interferometer using polarization heterodyne interferometry to translate the linear speed and kinematic direction messages into two low frequency signals. These two signals are then processed to achieve the purposes of analyzing the speed and kinematic direction by the signal processing system.A system combining the concept of polarized light and the techniques of laser interferometry & electronic circuits is proposed to measure the linear speed of moving solid and also recognize the kinematic direction simultaneously in this paper. The whole system is composed of the optical system and the signal processing system. The optical system suggests a modified Michelson interferometer using polarization heterodyne interferometry to translate the linear speed and kinematic direction messages into two low frequency signals. These two signals are then processed to achieve the purposes of analyzing the speed and kinematic direction by the signal processing system.