| Recently twenty years, the technology of digital image measurement, with the development of Laser technique, Precise and Optical technique, Computer technique and artificial intelligent identify technique, has been a new focus point of research in measurement field. It's based on Optics, and combines with Photo-electronics, computer technique, image-processing technique and other modern technologies to integrate with photonics, mechanics, electronics and arithmetic for making up a comprehensive measuring system. It's widely used in the dimensional measurement of geometrical quantity, delicate parts, the remote-sensing measurement of avigation and other technical fields relevant to image. There are numerous research directions and extensively applied realms and foregrounds. Digital image measurement means that the images are taken as the carrier of information, such as size information, shape outline information …etc. Based on the theory of vision, the size or the outline of practical objects can be achieved, using the technique of digital image processing to analyze the pictures which carry the information of objects. Making use of the image measurement, the paper takes measures to the size and the three-dimensional shape outline of objects, and details the correlation technique of image measurement. The main contents are as follow: 1. Using the existing of Digital image measurement system and experiment condition, we design and set up the system of measurement. The hardware includes the CCD camera, zoom lens set, four-port imaging collecting, 20mW neon-helium laser, the optical system, slit-shaped pore, the flat surfaces fixed point, PC machine, the precision angle turn set and the measured objects…etc. 2. The one-bye -one corresponding measurement scheme in the arrange of visual space is put forward based on the foundation of digital image processing and Optical imaging. The corresponding relevant information between the object space and the imagine space should be gained when interpolation method is used to make process with the object space data and imagine data. The data could be gotten when he flat surfaces fixed point is set up and imagine on the flat surfaces is coming to being with video camera and then processed. So the issue is simplified. It is more complicated and low-accurate to make demarcation on the video camera and lens parameter, however, the above-mentioned method just shunts it. It contributes a lot to make the measurement more approaching to the practice and to the adjustment and improvement of the experiment accuracy. 3. Combining the Babinet complementary and Fraunhofer slit diffraction theory with the above-mentioned calibration scheme, we create the measurement system of micro-size. Using the system we measure the filament diameter, at first, picture the diffraction fringe, then process the image data with centroidal and curve fitting methods. The method can get the measurement precision(0.6um) . 4. The process of tri-dimensions outline information transformed to the planar imagine information is discussed in details combining with laser triangulation measurement method and 3-D imaging mathematical model. The characteristic boundary of the planar imagines is confirmed as well. It is consisting of measured imagine and demarcated draft. At the same time, the imagines are selected, filtrated, central result analyzed etc using the imagine processing technology. The tri-dimensions information of the section line is received making use of the corresponding relation between the center point of the imaging space with the characteristic points on the demarcated draft and on the measured draft. 5. The tri-dimensions outline information could be gotten by the way of...
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