Encoding Multiple Information into European Article Number (EAN)-13 Codes with Various Chromic Sensing Materials to Construct Intelligent Barcodes

An intelligent encoding/decoding scheme for barcodes is studied that can realize transformation among different barcodes under external stimuli. The proposed scheme is compatible with the European Article Number (EAN)-13 encoding/decoding system. First, the transformation mechanism among different barcodes is analyzed. Two different transformation strategies, the bar transformation and the background color transformation, are discussed. To demonstrate the possible applications, a temperature-sensitive barcode tag (TSBT) and pH-indicative barcode tag (PSBT) are developed by embedding the corresponding thermochromic and pH-sensitive materials into the traditional EAN-13 barcodes. Except for the conventional identification function, these tags can be used as environmental sensors to sense temperature and pH values. The maximum recognition rates of the TSBT and PSBT are 100% and 98%, respectively. The technology is universal and versatile because different kinds of sensitive tags can be constructed easily. This sensitive barcode technology can be expected to provide an efficient, accurate, and low-cost solution to real-time detection.