Method of improving accuracy of CCD sugar concentration measurement system

LIN Hai-tang1， YIN Jian-jun1， XIANG Zu-feng1， TANG Jian-bin2
（1. College of Mechanical Engineering， Zhejiang University of Technology， Hangzhou 310014， China；
2. College of Information Engineering， Zhejiang University of Technology， Hangzhou 310014， China）

Abstract： To realize on-line precision measurement of sugar concentration，a measurement system integrated ARM of sugar concentration was developed by analyzing CCD philosophy of measurement，then the measuring system error was analyzed which had an effect on precision. The characteristic of edge gradient of CCD was analyzed，the algorithms of sub-pixel edge detection which applied the polynomial interpolation was used to improve the positioning accuracy of pixel. The experimental result shows that this system possesses superior resolution and measurement accuracy，compared to the traditional refractometer.
Key words： sugar concentration； linear CCD； sub-pixel； error analysis