Introduction to 2D barcode Because barcode technology has the advantages of fast input speed, high accuracy, low cost and strong reliability, it has been widely used in various industries. However, with the continuous expansion of the application field, the traditional one-dimensional bar code gradually shows its limitations: first, when using a one-dimensional bar code, the information must be extracted by connecting to the database to clarify the meaning of the information expressed by the bar code, so there is no database. Or where it is inconvenient to connect to the Internet, the use of one-dimensional barcodes is limited; secondly, one-dimensional barcodes can only express letters and numbers, but cannot express Chinese characters and images. In some occasions where Chinese characters are required, one-dimensional barcodes cannot It meets the requirements very well; in addition, in some occasions, the one-dimensional barcode with large information capacity is usually limited by the size of the label, which also brings inconvenience to the packaging and printing of the product. The birth of two-dimensional bar code solves the problem that one-dimensional bar code cannot solve. It can express information in both horizontal and vertical directions at the same time. It can not only express a large amount of information in a small area, but also express Chinese characters and store images. The emergence of two-dimensional barcodes has expanded the application field of barcodes, so the classification of two-dimensional barcodes used by many different industries can be divided into stacked two-dimensional barcodes and matrix two-dimensional barcodes. | 2d barcode label