Know more about 2D barcode

- Oct 14, 2017-

Know more about 2D barcode

Two-dimensional (2D) symbols, on the other hand, encode information both horizontally and vertically, encoding the data more efficiently and in less space than a linear symbol.  There are two versions of 2D symbols:

2d barcode1.jpg

The PDF417 symbol at the left is a stacked or multi-row 2D symbol. ("PDF" stands for Portable Data File. "417" comes from the method of encoding a symbol character.  Each character consists of 4 bars and 4 spaces and is 17 modules wide. These symbols are composed of bar codes stacked on top of one another.  LIke their linear symbol relatives, stacked or multi-row symbols encode data using combinations of bars and spaces.    PDF417 symbols encode personal information on the back of driver's licenses in 45 states of the US.

The preceding paragraph is encoded in the PDF417 symbol above.  It could have been scaled much smaller, but that makes it difficult to identify the individual rows of linear symbols.

2d barcode2.jpg

QR (Quick Response) Code is a Matrix 2D symbology, encoding data based on the positioning of dark elements on a light background. Decoding the QR Code symbol at the left will provide you with information about the author.

QR Code was created in 1994 for the purpose of allowing the contents of the symbol to be decode at high speeds.  Today QR Code is a registered trademark of Denso Wave and an ISO standard (ISO/IEC 18004) with a free license to use.

QR Code is capable of encoding more than 7,000 characters in a single symbol, whereas a single bar code symbol typically stores around 20 digits.  A QR Code symbol encoding the same 20 digits woudl be one-tenth the size of the bar code. 

QR Code is easily recognized because of the distinctive square "position detection patterns" at three corners of the symbol, allowing the symbol to be easily found and decoded by a QR Code reader in any orientation and at high speeds.

There is also a version, Micro QR Code, that saves space by using only one position detection pattern. 2d barcode3.jpg

MicroQR code can store only a maximum of 35 numeric characters, but it was designed for applications with only a small amount of marking space available, such as on printed circuit boards and electronic parts.

Very recently, another version, dubbed iQR Code, was developed for the industrial market.  It has an even higher data capacity in a smaller space and can be created ina  rectangular format.  To dta, readers for the new version are available only in Japan, so it will likely be a while before a rectangular iQR Code will be seen outside of Japan.

It's unlikely that the B2B applications for iQR or Micro QR Code will ever be as creative as the B2C applications for the basic QR Code symbol have become.

2d barcode4.jpg

For example, QR Code now comes in more colors than just black and white -- and in designer styles!  The symbol at the left is not only attractive, but it will take you directly to the embedded designer's link.

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