The two-dimensional barcode
2D-barcodes are classified into Matrix Codes, such as QR, Data Matrix, Aztec, Code One, as well as Dot Codes, like the Dot Code A and stacked codes, such as PDF 417, Codablock and Code 16K. We will now focus more closely on the QR-codes, mainly those from marketing, adverts and public relations and DataMatrix-Codes, which are mainly used within the industrial sphere and in logistics.
QR is the abbreviation for „Quick Response“, i.e. rapid answering, which refers to a very fast access to the information encrypted by the code. The QR-Code was developed by the Japanese company Denso Wave (daughter-company from the Toyota Group) in 1994. Two components were to be provided: More information in a smaller space and a higher read-tolerance in case of incorrect codes. The QR code made its way in advertising and public relations and serves for these areas as a marketing instrument.
What is a QR-code composed of?
The QR-code is composed of a square matrix (black and white squares) which represents data in a machine-readable manner. There is a special mark in three of the four edges of the square, and this mark indicates the orientation.
1. The position marks are indicating the direction in which the code is printed.
2. In case of a large-scale code, the orientation marks in turn serve as an orientation aid.
3. The synchronization lines, also known as, tact cells, indicate to the scanner how large the data matrix is.
4. The marked fields are indicating the version.
5. The format fields contain information regarding error tolerance and the code data mask. Additionally, they simplify the scanning process.
6. The small squares serve for encrypting information.
7. The quiet zone enables the scanner to differentiate the QR-code from its surroundings.
How high is the error tolerance and the QR-code capacity?
Due to the horizontal as well as vertical information display (2-dimensional), the QR-code requires only one tenth of the place in comparison to a common barcode. Apart from that, the barcode is less prone to getting dirty or damaged thanks to the error correction level. The error correction level which we can select even during the QR-code establishment, serves to define the error correction level, to keep the code readable even if it is damaged or gets dirty. On the highest level, even 30 % be damaged but readability is still provided for.
A QR-code can contain up to 7.089 digits or 4.296 letters as well as punctuation marks or special characters. Apart from numbers, also words or sentences, and hence internet addresses can be encrypted. The more information is encrypted in a QR-code, the more code structure is established.
How do we create a QR-Code?
Creating a QR-code is easy and simple. First, you go to a QR-code website and select which functions the code is to perform and then you type in the respective data. By clicking on „QR-Code erstellen“ (i.e. „Create a QR-code), your personal QR-code is created. Following the decision in which format the QR-code is to be displayed, you can then download the file.
How do we scan a QR-code?
First, you need a smartphone scanner-app and such apps are available in the App-store in a large variety. You scan the QR-code by holding your camera above the code which is to be scanned. If the code is readable and is now automatically called by the encrypted address or activity.
QR-code fields of application
The QR-code became wide-spread, among others, thanks to the "Open Source" technology – i.e. due to being available to everybody. The decisive advantages in comparison to a common barcode (stripe-code) consist in a larger data capacity and a high error tolerance. By now, the QR-code has proceeded into the mobile marketing sphere thanks to the widespread use of smartphones.
Popular QR-code application areas are:
- Print adverts, advert posters and showcases
- Transport vehicles and mobile ticketing stations
- Point of Sale
- Business cards
In cases where you reach the limits of barcodes QR-codes, you come across the DataMatrix-code when looking for alternatives. It has been developed in the late 1980s in the USA a and represents one of the most popular 2D-barcodes. Since the time when it was invented, the DataMatrix-code has undergone several development stages. Both the QR-code and the DataMatrix-Code are normed by an international organization (ISO) and are being used worldwide.
What is a DataMatrix-code composed of?
The DataMatrix-code is composed of several components, just like the QR-code. A person aware of these components, can easily distinguish a DataMatrix-Code from other two-dimensional barcodes.
The searcher is a continuous line in the lower, left corner. It serves for sample detection and for calculating the DataMatrix-code turning position.
The outer tact cells serve for identifying the amount of lines and columns. These cells actually indicate the matrix density.
The storage area displays binary encoded information.
The quiet zone represents an empty zone surrounding the storage area. It does not store information but distinguishes the code from other patterns or structures that are possibly surrounding code.
How high is the error tolerance and the DataMatrix capacity?
A lot has happened between the first DataMatrix-code variant, the ECC00 and the ECC200 which is currently in service. ECC is the abbreviation for Error Correcting Code, i.e. it´s about an error correction carried out via a reed-solomon-algorithm. This means that a DataMatrix-code damaged by 25 % can still be entirely read out. Depending upon the symbol size and the exterior form, a different data volume can be played back. As far as square matrix codes are concerned, the symbol size ranges from 10 x 10 up to 144 x 144, which grants a data volume ranging between 1 and bytes. Rectangular codes can have a symbol size of 8 x 18 up to 16 x 48 reaching thus a data volume between 3 and 47 bytes.
How do we create a DataMatrix-code?
Creating a DataMatrix-code is equally fast and simple like the QR-code establishment. There are various websites generating DataMatrix codes for free. By clicking on „DataMatrix-Code erstellen“ (i.e. „Create a DataMatrix-code), your personal DataMatrix-code is created.
A label- and laser-printer is enough to print a DataMatrix-Code. Many of these devices already had the conditions for printing 2D-codes implemented and can print a DataMatrix-code on paper.
Today, mainly laser labelling systems are used for direct labelling. In these cases, the DataMatrix-code is directly burnt e.g. on engine parts, plates or similar objects. Doing so, the code is engraved into an industrial engine material.
How do we scan a DataMatrix-code?
A camera system is necessary to read out the DataMatrix-code information. Only this provides for detecting the code structure and depicting it. The DataMatrix-code is lighted by a light source, the reflected light is subsequently detected and analyzed. You can use various devices to do this:
- Mobile Computer
- Hand Scanner
What are the DataMatrix-codes application areas?
This device is most widely used in the industrial sector and in logistics. The DataMatrix-code is mostly used for direct laser engraving markings, but it is also used more and more for document handling purposes such as for parcel sending or ticketing.
Popular DataMatrix-Code application areas::
- Marking industrial machines
- Pharma industry applications
- Electronics and semiconductor industries