Types of barcodes used in the label and packaging industries

Commonly referred to as the barcode ‘Symbology’, barcodes - depending on their use - all string together a combination of numbers, alphabetical characters or symbols as a set of bars and spaces that are machine-readable. Some may also incorporate a unique number that has been allocated by a governing body. They can be automatically read to provide a fast, accurate and efficient method of collecting and recording data.

Some of the main barcode application areas used within the label, packaging, shipping and distribution sectors for product identification, checkout scanning, tracking or tracing are set out below.

These include:

• Retail barcoding

• Outer packaging barcoding

• Pharmaceutical barcoding

• Automotive industry

• Aerospace and defense

• Parcel distribution

• Coupon barcoding

Little more than a handful or more barcode symbologies, described in various industry standards for barcodes, are used throughout these sectors and these are explained in the following article.

RETAIL BARCODING – UPC AND EAN CODES

Special number and code systems for use in retailing have been developed and in use since the 1970s and these are based on either the GS1 North American UPC (Universal Product Code) or the GS1 EAN (European Article Number) code. In these systems, each retail product is assigned a unique manufacturers number which can be used instead of the full product description in all transactions that take place between manufacturer, distributor and retailer.

The first part of a retail barcode tells you the country where it was issued; the next part identifies the manufacturer of the product; the final part of the barcode, allocated by the manufacturer, identifies the product itself. At this stage the code is purely number-based to aid communication and does not yet depend on a symbol, barcode or scanner.

The UPC symbol is made up of 10 characters that appear in figures below the symbol. Once numbers have been allocated it is possible to convert this to a special barcode known as The Symbol, which is made up of a combination of the thick and thin black-and-white vertical bars. The structure and layout of both UPC and EAN symbols is very similar, shown here using a UPC symbol.

As already mentioned, the UPC symbol is made up of ten characters that appear in actual human readable figures below the symbol. A number system character appears halfway up the left hand margin.

The various elements that make up the UPC symbol are: (a) a number system character which defines the application, e.g. retail groceries, drugs, etc. (b) start and stop bars to signal to the scanner the beginning and end of the code (c) number system character code bars (d) check digit code bars (e) actual number (f) corner marks.

UPC-E is a variation of the standard UPC which allows for a more compact barcode by eliminating ‘extra’ zeros. Since the resulting UPC-E barcode is about half the size of an UPC barcode, UPC-E is generally used on products with very small packaging where a full UPC barcode couldn't reasonably fit.

The EAN symbol is also made up of ten characters, plus country of origin and number system. These again designate the manufacturer and the product – the same as with the UPC symbol – and appear in actual figures beneath the code.

This time however, there are two additional characters at the start of the code. The first appears to the left of the guard bars; the second is incorporated into the characters beneath the code. These additional characters represent the country of origin and the number system.

A check digit character also appears at the end of the line. This means that the EAN Symbol has thirteen numeric characters; the UPC Symbol has ten (plus one halfway up the margin).

EAN-8 is the EAN equivalent of UPC-E in the sense that it provides a ‘short’ barcode for small packages. As can be seen in the following graphic, an EAN-8 barcode is shorter than an EAN-13 barcode, although somewhat longer than an UPC-E barcode.

Codabar – An older barcode symbology of 16 encoded data characters; 0 - 9, 6 special characters and 4 unique start/stop characters. Each character has 7 elements (4 bars and 3 spaces).

Originally designed for use in retail price labeling, it was one of the original proposed symbologies for the UPC. However, it found a niche in diverse non-retail applications.

Codabar is the code required by the US Department of Defense. Other applications include inventory control, libraries, blood banks, air bill applications and photo finishing.

Code 39 - Code 39 (3 of 9) is an adequate general-purpose secure alphanumeric barcode symbology that is in very wide use world-wide and which encodes 43 data characters. Its major advantage is that both alphabetic and numeric characters can be encoded; 0 - 9, a - z, 7 special characters and stop/start character. Any length of data can be encoded.

Code 39 is generally the preferred symbology when alphabetic and numeric characters are required. It is the most widely used code within commerce and industry. A limitation is that the code is not especially compact, which can lead to practical dimensional constraints on small items, labels or packaging.

Although the code is not as compact as Code 128, it is still heavily used in the automotive industry and by the US Department of Defense.

Code 128 - Code 128 is a continuous barcode in which any length of data can be encoded. It encodes the entire 128 ASCII character set, including all digits, character and punctuation marks. Such a broad range of characters makes the code very powerful, enabling it to store diversified information in the barcode. It is also fairly compact, which gives it a good data storage to size ratio. The code has excellent density, high reliability and is in very wide use world-wide, particularly for logistics related to ordering, distribution and transportation.

Code 128 is mainly geared to non-point-of-sale applications.

Interleaved 2 of 5 - A numeric-only, bi-directional, self-checking barcode symbology consisting of five bars, two of which are wide. In this code both spaces and bars carry information, and there must be an even number of characters in the code.

The ‘Interleaved’ part of the name comes from the fact that a digit is encoded in the bars and the next digit is encoded in the spaces. The encoded digits are therefore ‘interleaved’ together.

There are five bars, two of which are wide and five spaces, two of which are wide. The symbol can be as long as necessary to store the encoded data and can hold up to 18 characters per inch.

Interleaved 2 of 5 (ITF) is the most popular numeric only barcode in non-retail distribution and is the recommend symbology for corrugated shipping containers. It has also been selected for use on other shipping containers in the grocery industry. Its main advantage is its density.

The standard ITF contains 14 digits, with an optional 6-digit suffix.

The ITF code is mainly used for warehouse inventory. The code is also accepted in airline ticketing and baggage and cargo handling.

TWO DIMENSIONAL AND OTHER BARCODE SYMBOLOGIES

Whilst most barcodes are continuous codes that carry information in one direction, other codes have been developed that can carry information in more than one direction.

2D bar codes - Unlike conventional barcodes, 2D barcodes are able to carry information in both horizontal and vertical planes, enabling more information to be printed in a smaller amount of space. Many 2D barcode symbols can carry 2,000 characters of data in a single symbol, as compared to a regular or linear barcode capacity of 10 to 22 characters. They can also carry binary data, which can be made to run a computer program or generate photographs or drawings.

2D barcodes are being used in applications where there is a limited amount of space and for the coding of high cost sophisticated devices where the code may need to contain a list of components, serial numbers and/or manufacturing history.

2D matrix codes - Matrix codes have a checkerboard appearance in which each uniformly spaced square or polygon-shaped cell corresponds to a binary bit. They are made up of a mosaic of light and dark elements that must all be read before any characters can be recognized. They only have one width, so the scanner must read the center of each bar to interpret the code. See also DataMatrix Code.

DataMatrix code - A proprietary dynamically variable 2D (two-dimensional) matrix code, which provides a visual representation of a machine executable electronic binary code.

The symbology is based on the position of black elements of a regular profile (round, rectangular, etc) within a two-dimensional matrix. Each element is the same size and it is the positioning of the elements that defines the data contained in the code.

Matrix codes have many times the data storage capacity of conventional bar codes and may include photographs.

The code can range in size from .001 inch square (0.65 sq. mm) to 14.00 inches square (9032.24 sq mm) and has a capacity of between 1 and 2,000 characters in any language and can be read at any angle of rotation. It is especially suited for making very small codes.

For security applications, matrix codes may be printed on labels or packs with invisible UV-sensitive ink that only becomes visible when illuminated with light outside the visible spectrum (‘black light’). High-resolution printing is not required to achieve reliable recognition. Printing is feasible by all types of marking devices - computer printers, dot matrix, ink jet, laser, thermal transfer, and lithography - in any color combination that provides about 205 contrasts. Invisible codes can be read with the same speed and accuracy as visible data codes.

Code 49 - The first truly two-dimensional barcode to be developed, responding to strong demand to condense a high-volume of coded data into a symbol with a small surface area. The code is built up from a series of one-dimensional barcodes stacked one above another. Each complete Code 49 may comprise between 2 and 8 rows, according to data volume storage requirements.

Aztec Code is a two-dimensional matrix symbology containing dark and light square data modules. It has a finder pattern of concentric square rings centered on a single dark module located in the center of the symbol. A two-dimensional imaging device such as a CCD camera is necessary to scan the symbology. Aztec Code can encode all 8-bit values (0-127 ASCII and 128-255 ISO 8859-1, Latin Alphabet No.1). The Aztec Code is used for small item marking applications using a wide variety of printing and marking technologies.

Datastrip2D – Originally called Softstrip and the oldest of the two-dimensional symbologies, Datastrip is a variable-size, variable-density two-dimensional bar code symbology offering a very high data capacity. The symbology has a unique combination of matrix density and variable rectangular aspect ratio and handles large data capacity in a single symbol, typically 2800 bytes and above.

It is a patented encoding and scanning system that allows data, graphics and even digitized sound to be printed in a highly condensed format and then read error-free into a computer. The code must be read by a special reader from Datastrip, Inc. and the reader must be in contact with the code.

The code is regarded as of most interest for the printing of information on ID cards.

PDF 417 – A high density, two-dimensional barcode with a high information capacity in a very small area. Normal codes may store up to 20 characters per symbol; PDF 417 symbols can carry up to 1,800 characters per symbol. Large amounts of text and data can be stored inexpensively and securely with the PDF 417 two-dimensional code and the printed symbol can withstand a certain amount of damage without causing any loss of data; a level of error correction which is far more advanced than normal one-dimensional barcodes.

PDF 417 2D barcodes can be printed from within any MS Windows application using a licensed package or site license from a variety of specialist supplier sources.

MaxiCode is a fixed-size (approximately 1 inch by 1 inch/25.4mm x 25.4mm) 2D matrix barcode symbology which is made up of offset rows of hexagonal modules arranged around a unique finder pattern. MaxiCode was originally created and used by United Parcel Service (UPS) for tracking and managing the shipment of packages.

A MaxiCode barcode can encode 256 international characters. Although the capacity of a MaxiCode symbol is not as high as other 2D matrix barcode symbologies, it was primarily designed to encode address data. The maximum data capacity in a single MaxiCode Symbol is 93 alphanumeric characters or 138 numeric characters.

Mobile action codes - Printed 2D/QR codes, matrix codes, digital watermarks, Microsoft MS tags, embedded NFC, or other forms of printed mobile action codes, placed on labels, packaging, hang tags, posters, displays, etc., to enable individuals to instantly access a brand owner's website or on-line services with their smart phones, in turn triggering an interactive experience that can bring life to a printed label or packaging substrate.

Mobile action codes now appear widely on product packaging, in shopping centers, malls and retail outlets and take consumers to different types of retail outlets and take consumers to different types of HD Barcode from Complete Inspections Systems locations, such as loyalty programs, social media, location based discounts, special offers, opportunities to win prizes, additional information about products, and the downloading of user instructions.

Quick Response (QR) codes - Codes that can be embedded into labels, product packaging, hang tags, store displays, to create an immediate and personalized connection through smart phones and dedicated QR reading devices so as to engage, educate and convert consumers. They can link directly to text, e-mails, websites and phone numbers.

Conventional barcodes are normally seen as a collection of vertical lines; QR codes are different in that the data on them is stored in both directions and can be scanned vertically or horizontally. Although a standard UPC or EAN barcode can store up to 30 numbers, a QR code can store a massive 7,089 numbers. It is this amount of data that enables links to websites. Matrix codes may be printed on labels or packs with invisible UV-sensitive ink that only becomes visible when illuminated with light outside the visible spectrum (‘black light’). High-resolution printing is not required to achieve reliable recognition. Printing is feasible by all types of marking devices - computer printers, dot matrix, ink jet, laser, thermal transfer, and lithography - in any color combination that provides about 205 contrasts.

Quick Response (QR) code

A QR code can be a serial number on a bottle of wine or a unique reference that includes a batch code, use-by date and unique code on a pack of medication. These are examples of how consumers can acquire further useful information that informs them and the brand owner about the ‘status’ of the product they have just purchased or are about to consume. Adding a printed QR code to a printed label or package is relatively straightforward and can be introduced at a minimal cost.

QR codes are available in a variety of formats and different reader Apps and can be black-and-white or in basic colors. They are best suited to simple designs that do not require integration with brand graphics.

In addition to the product market sectors already mentioned above (pharmaceuticals, liquor and so on), serialization is also being used in automotive replacement parts, electronic components, computer components and peripherals such as routers and hard drives and in fashion products such as apparel, footwear and designer items such as handbags, luggage and eyewear.

SnapTag - Invented by SpyderLynk, a SnapTag is a 2D mobile barcode alternative similar to a QR code but which uses an icon or company logo and circular code ring rather than the more traditional square pattern of black dots. The SnapTag has been adopted by Toyata Motor Sales USA and used across multiple marketing and branding initiatives to engage consumers throughout the U.S.

The technology was also used in a mobile campaign for Coors Light, official beer sponsor of the NFL and Superbowl XLV. The interactive mobile campaign delivered the chance to win instant and sweepstake prizes for Coors Light fans. A further user in the drinks industry has been AC Golden for their Colorado Native Lager which, when delivered to the table, interacts with the consumer through a SnapTag incorporated in the Colorado logo.

SnapTags offer a QR code alternative that puts brand identity front and center. They are easy to activate and can be used to take consumers to a brand’s website and can also enable mobile purchases, coupon downloads, sample requests, video viewing and promotions. See also QR code. 

Snowflake code – A code made up of an array of discrete dots in which more than 100 numeric digits can be encoded within an area of 5mm square (0.0078 sq. inches). The code can still be read even with up to 40% of the code damaged due to user selectable error correction. The code can be applied directly to products or in a label form.

Invisible bar codes - These make use of near infra-red fluorophones which are invisible to the naked eye. They produce visible fluorescence when subjected to laser light from a scanner. The inks used for invisible bar code reading are available for both ink jet and flexographic printing and are targeted at applications in the packaging of cosmetics, pharmaceuticals and luxury goods.