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This paper presents a new phase unwrapping algorithm to deal with the problem of phase restoration from an interferogram that is in presence of both high-level random noise and segmented disconlinuity. The algorithm is based on a composite template matching to simultaneously identify unreasonable phase jumps caused by speckle noise and segmented discontinuilies such as holes and borders in the wrapped phase map. Examples unwrap with the inteiferograrns generated by the computer and real speckle fringe patterns taken from double-pulsed speckle interferometer are included to show that the technique is efficient and simple to implement.

For 3D digital measurement of large scale objects, image mosaic is the key technology to achieve whole measurement for a small measuring field of the sensor unit. A viscous-target-based three-dimensional image mosaic technology is proposed. The screw theory is introduced to realize the spatial image mosaic. The method permits an automatic identification of targets and a better matching for the feature coded technology. In experiments, the method was proved to be valid, with a relatively high precision on three-dimensional image mosaic. The relative error of the space length measurement is less than 0.6%.

Porous silicon with pore size in the range of a few nanometers can be used as multifunctional material in different MEMS applications. Via an electrochemical etching method, porous silicon is fabricated on the silicon substrate and removed as a sacrificial layer by using KOH solution to form a micro structure. This technique is typical in micro fabrication. Three-dimensional size is the basic geometric feature to describe microstructure surface characteristics. It is important to investigate measurement methods for it. UBM Microfocus Measurement System based on defocusing error detection is adopted to measure eroded depth of silicon cup. The measured data in the experiments are analyzed. The influence of etching time, current density and silicon type on etching depth can be acquired. Effective reference data can be provided for studying micro fabrication methods.

This paper describes a system that detects and categorizes workpieces with random defects on electrodeposits glossy metal surface. The system is developed on the basis of combination CCD photoelectricity inspection technology, image processing and automatic control technology. In the system, a special illumination apparatus with a light source of diffused light is designed. Workpieces with defects are automatically selected through measurement with image enhancement retreatment, gray scale analysis, image binaryzation, feature extraction and image recognition. Hardware comprises sections of optics, image collection, and control circuits. Software is programmed in Visual C++ and assembly language. The system can resolve the difficulty of detecting random defects on surface under the conditions of high reflection and complex surfaces.