A binary code symbol for non-linear strain measurement designed specifically for perimeter-based deformation and strain analysis. The symbol is rectangular with a continuous outer perimeter, two data regions along adjacent sides of the rectangle and a utility region adjacent each side opposite the data...http://www.google.com.tw/patents/US7533818?utm_source=gb-gplus-share專利 US7533818 - Binary code symbol for non-linear strain measurement and apparatus and method for analyzing and measuring strain therewith
