An introduction to barcodes and barcoding technology

Many people also collect peel-off labels, redeemable vouchers or coupons which will contain a barcode that registers money-off, two-for-one, or a discount on another product or on fuel. These vouchers are often found on products, in magazines, newspapers, or printed-out at the till at the end of a current purchase.

Indeed, barcodes are probably so common today that many consumers hardly even notice them anymore. Yet they see them every day when they shop, with the purchased items – or with discount coupons passing through electronic scanning checkouts or bar code reading handguns. It’s only when a barcoded item doesn’t scan and the code then has to be manually keyed in, that the code’s importance comes into focus.

It’s perhaps even more critical for barcodes to scan and read accurately when it comes to their use in the medical field with applications as diverse as drugs, blood banks or in pharmacies. Here, barcodes are used to track the source, batch and date, in addition to validating the drugs. Aside from the healthcare and pharmaceutical supply chain, barcodes are used in blood banks, hospitals, at the bedside, on patient records, all ensuring patients are administered the proper drug, doses and treatments.

In these types of medical and related fields, some label printers offer complex self-adhesive label constructions for medical packaging presented on roll, in sheets, in pads, or in fan-folded packs. Special barcode label constructions with bullets or other features in conjunction with variable data might also be produced. Such labels can be the difference between the life and death of a patient. Being able to verify that an item is genuine through accurate tracking and tracing, rather than a counterfeit, can be an essential part of the pharmaceutical and medical distribution process.

Strict quality control measures are required throughout the medical label manufacturing process to ensure that all of the barcode labels produced meet the exacting specifications laid out in the relevant standards. It is certainly important that label and pack producers verify their barcodes to GS1 or other relevant standards in order to minimize risk and prevent any barcode-related errors. The same kind of exacting requirements can also apply to standards set for the automotive, defense, aeronautical, electronic or electrical spare parts components sectors.

The automotive industry for example, first developed standards for barcodes used for tracking parts throughout the supply chain back in 1984 using a standard format called Code 39. The automotive industry also uses a unique serial number known as a VIN or vehicle identification number to identify individual motor vehicles.

The VIN is an automotive industry application standard that defines specifications for printing a Code 39 representation of the unique VIN on to a label to be attached to each motor vehicle. This sets the vehicle apart from all the millions of other vehicles on the road.

Similarly, suppliers of goods to the Department of Defense (DoD) are under a mandate to comply with MIL-STD-130 for identification and tracking items at unit level, box or case level, shipping containers and pallets throughout the defense contractors supply chain. An added requirement for a unique identification number (UID) . a 2-dimensional data matrix encoded with the specific CAGE code which must last the expected life of the product may also be necessary with some supply contracts.

Barcodes and barcode scanners are also found in places like libraries for initially checking books out then again on their return. They can also be found in use when signing in for a job or production process and, in miniature form, have even been used to tag and track honey bees.

Put together, the current uses of barcodes include the whole field of high street retailing, outer case coding, inventory control, asset management, job costing and pricing, production control, scheduling, materials control and management, in the parcel distribution services and in many other time consuming operations that would benefit from automating the process. Labels are the prime carrier of the barcodes for a great many of these applications.

Much more recently, new developments in codes have seen the successful introduction and use of two-dimensional (2D) matrix codes, as well as Quick Response (QR) and Augmented Reality (AR) codes which have become very familiar to those with smart mobile phones. 

While traditional barcodes can handle up to 20 digits, QR codes for example, can hold up to 7,089 characters and yet take up a tenth of the space of a normal barcode. They therefore open an even wider range of applications for the future, linking the virtual and physical worlds by making access to information much easier to manage.

FIRST INDUSTRIAL APPLICATIONS

While barcodes can be described as an essential element of today’s retail, industrial and commercial life, it has not always been that way. Industry leaders in the United States grocery trade first began seeking out new methods to both improve efficiency and to gather information about customers’ shopping habits back in the late 1940s.

However, it was only towards the end of the 1960s that the first industrial applications for coding were being developed and not until April 1973, little more than 40 years ago that an industry standard (the UPC system) transformed barcodes into a viable and profitable business proposition in North America and led to the birth of automated scanning checkouts in grocery and other retail stores.

This encouraged printers to develop new technology in the form of barcode film masters, inks and plates to enable them to reproduce the codes within exact tolerances. Financial considerations at the time (1970s) showed that the barcode revolution would mean that each of the USA’s multi-thousands of grocery stores would need to spend about $200,000 each on new equipment to enable them to utilize the codes.

They would also have to install new data processing equipment and retrain their staff. Manufacturers would potentially have to spend collectively in the region of USD 200 million a year on labels. But the indications were that they would achieve a ROI in a fairly short period of time.

Code standardization meant a standard system of numbers would be needed. With the introduction of UPC all individual companies had to relinquish their own bespoke methods and register with a new Uniform Code Council (UCC).

By the late 1970’s nearly 85 percent of all products in North American grocery stores carried the standardized UPC codes. However, even by 1978 less than 1 percent of grocery stores nationwide had scanners. This increased to 10 percent in 1981 and 33 percent by 1984. Currently about 95 percent now use scanners in even the smallest stores.

Other applications for barcodes were also being introduced and are still used today including courier companies, postal services, patients’ ID in hospitals, tracking medical records, distribution companies identifying for picking purpose etc., even marathon runners. Every courier service now uses barcodes extensively as do airlines for tracking baggage.

By 1977, retail barcoding was beginning in Europe. This was when the EAN code, which was chartered in Belgium, started to be used by the, then, 12 countries of the European Community.

The code is now called GTIN (Global Trade Item Number), but it wasn’t until 1990 that the American Uniform Code Council and European (EAN) barcode committees signed an international agreement to formalize a global approach to barcode standards. Strangely enough it was not until 1997 before a joint meeting between the two Boards occurred in Chicago.

In 1978 The Fine Fare supermarket was the first retail organization in the UK (probably in Europe) to use barcodes on its own label products and the first company in the world to incorporate a velocity code on the film masters for the production of the dark vertical bars on the codes. The benefits of the velocity code printed alongside the symbol enabled the checkout operator to know where to look for the code and there was no need to manually label each item, saving time and money. The first order for own labels to include barcodes ran to 10,000 miles of labels!

Even up to around 1983 at least seven different barcode systems were still in use, leading to a lack of standardization throughout the industries in which they were being used. This has now been reduced, depending on which industry they are used in.

Further details relating to the structure and format of barcodes can be found in within this series, as well as a review of some of the most commonly used barcoding symbologies and guidance on barcode selection.

BARCODE READING

While the use of barcodes has rapidly spread to almost every aspect of retail, industrial and commercial life, they would not be of any use unless the black-and-white lines that make up the code could be quickly and easily read and the information transferred to a computer or an in-store checkout terminal.

Devices that read barcodes - the input devices - are known as wands, CCDs readers or scanners. The selection of what input device to use depends on the particular barcode symbol being used and its size; on the demands of the particular reading or scanning application; and on the connectivity or interface that is required to link to a computer or terminal. The job of the interface is to provide the direct connection between the barcode reading device/decoder and the computer. Barcode scanning equipment may also include barcode software, a barcode printer and consumables.

Barcode reading/scanning devices will typically contain a barcode decoder. The input device reads the barcode and transmits the data to the decoder, which in-turn converts the black-and-white barcode image to ASCII data. The interface is the connection between the decoder and the computer or terminal which interprets the information.

In use, the reader’s scanning head shines an LED or laser light onto the barcode. This light reflects back off the light and dark areas of the barcode and into a light detecting photoelectric cell(s). As the scanner moves across the barcode (or the barcode past the scanner), the photoelectric cell detects each part of the black-and-white barcode in turn and an electronic circuit attached to the scanner converts these on/off pulses into decimal numbers . giving a decimal number as the output.

VERIFICATION OF BARCODES

Barcodes have proved to be a fantastic asset in a wide range of retail, industrial and commercial sectors but, if for some reason the code does not scan or read accurately, then it can be costly and time consuming for both the supplier and the user – as well as embarrassing for both. Indeed, many major retailers make it compulsory to have a verification report before barcode labels are submitted and may return goods to suppliers, or even impose heavy fines on suppliers that have provided sub-standard barcodes.

Reports suggest that even after 25 years of barcoding some 7 percent of retail barcodes still fail to scan at the checkout, causing checkout queues, unhappy customers (and checkout employees) as well as store inefficiencies.

In use, barcodes therefore need to scan first time, every time. Many retailers and other users today demand . or as already mentioned, even make it compulsory . that their supplier gets barcodes verified before they are supplied to the store. This means that, in practice, barcode verification to international standards has become an important quality control tool for label and packaging producers.

Barcode verification is used to measure the printed quality of a barcode to an international (ISO) standard. In retail, the relevant standard is now used by retailers worldwide and is mandatory for all companies that design or print barcodes, so ensuring that acceptable bar code images are created.

ISO grade barcode verifiers are scientific devices that take precise measurements of each individual bar and space, and the amount of light reflected from each so as to check reflectance, contrast, light margins, bar gain, defects, as well as to decode and approve the check digits.

Barcode verification equipment, which may be PC-based, portable or on-line, can generally be categorized under five headings:

• Optical measurement equipment

• Wand verifiers

• Opto-electrical equipment 

• Laser vefiers

• On-line verifiers.

BARCODE GLOBALIZATION

A significant milestone in the global reach of barcoding was the decision in June 2003 for EAN to change its name to GS1 to reflect the global reach of the organization, although it wasn’t until 2005 that GS1 was launched worldwide. A year later more than 5,000 companies were using the Global Data Synchronisation Network (GDSN). Currently more than 10 billion scans are made every day worldwide.

Today, barcoding is a global phenomenon, with new standards continuing to be developed and used. 

Around the millennium the joint global tag (GTAG) program to supply a standard for RFID applications was introduced. In the same year GS1 issued guidance on which barcodes could be used with mobile phones. Also later in that year Nestle, Kraft, J&J, Walmart, Metro and Carrefour led the GS1 MobileCon initiative to define open standards to allow consumers and businesses to interact using mobile phones.

But just what are barcodes, how are they produced and how do they work? Are there different types of barcodes for different end-use applications, and how are barcodes verified, read and used in practise? In other articles, we explain with example codes and code formats the technology of barcodes and then guide readers through the machines, equipment and scanning systems that enable barcode reading.