A New Type Of Silicon Wafer Counting Machine

In the process of the production of solar silicon wafer, an important topic, is how to measure the quantity of silicon wafers in a fast, accurate and non-contact way. Now some types of counting machines already exit in market. But there are always some shortages in these machines, some are low precision, some are low measuring number. A new type of counting machine which is based on image processing technology was designed and realized. The advantage of this machine is that works can put the whole box full of wafers on the sliding platform, and get the total number of wafers after scanning, meanwhile our hands can never touch the wafers completely. The basic principal of this machine is that: drive the slider platform to move, scanning to get a set of images sequence, then compound all images into a whole panoramic image and then count the number of wafers by a special image recognition algorithm. My counting system generally go through following several designed steps before completely forming: the confirmation of basic measurement, the construction of experimental platform; the design of image system and the improving of light source; the design of image mosaic algorithm, and some improving to achieve a better precision, and use of Open CL library in order to meet requirement of real-time measurement. The design of image recognition algorithm, using the method of Fourier transform to analyze the thickness of wafer, use of algorithm of random sample consensus to overcome the error, in order to get a good precision; the design of multithread to get a real-time requirement and a fluent user experience; the design of database and preview control to show the result of measurement and so on.