Understanding Bar Codes
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The document provides a comprehensive overview of barcode technology, focusing on various types including UPC, QR codes, and data matrix codes. It explains their anatomy, common uses, and the algorithms behind their functionality, emphasizing efficiency and error correction capabilities. Additionally, it touches on how these codes bridge physical and digital realms in businesses, particularly in sectors like healthcare and retail.
Understanding Bar Codes
- 2. TABLE OF CONTENTS UPC Bar Code How They Are Commonly Used … 4 Anatomy of A UPC (A) Bar Code … 5 UPC (A) Bar Code Glossary … 6 How It All Works … 7 Testing The Algorithm … 8 QR Code How They Are Commonly Used … 16 The Anatomy Of A QR Code … 17 QR Code Glossary … 18 How It All Works … 19 2D Bar Code / Data Matrix How They Are Commonly Used … 10 Anatomy Of A Data Matrix … 12 Data Matrix Bar Code Glossary … 13 Benefits of The Data Matrix … 14 2
- 3. UPC BAR CODE The UPC ( A ) bar code symbol, is one of the most common applications of bar code technology and is seen on products everywhere. 3
- 4. HOW THEY ARE COMMONLY USED Bar codes are everywhere and they are used to identify everything from auto parts to hospital patients. The Universal Product Code is used to identify retail items in virtually every store and market in the country. 4
- 5. THE ANATOMY OF A UPC (A) BAR CODE 95 MODULES WIDE! LEFT GUARD! CENTER GUARD! THE FIRST SIX FIGURES DEFINE THE MANUFACTURER’S IDENTIFICATION NUMBER RIGHT GUARD! THE NEXT FIVE DIGITS ARE THE ITEM NUMBER MANUFACTURER IDENTIFICATION NUMBER CHECKSUM DIGIT MANUFACTURER ID CODE ITEM NUMBER 5
- 6. UPC (A) BAR CODE GLOSSARY UPC: Universal Product Code MODULES: The vertical bars that make up the bar code symbol. Numbers are created by patterns of filled and unfilled modules. 84 modules are used for digits, and 11 are used for the guards that define the symbols boundaries. GUARDS: Left and right guards mark the beginning and end of the symbol and the center guard marks the division between the manufacturer and product codes. MANUFACTURER CODE: Is made up of the first six digits and is distributed and managed by the UCC (Uniform Code Council). MANUFACTURER IDENTIFICATION NUMBER: Used to identify the particular numbering system used by the manufacturer. ITEM NUMBER: Assigned to each product and is defined by the last five digits. CHECKSUM: A single digit used for error checking. 6
- 7. HOW IT ALL WORKS First, the scanner flashes a laser across the code reading the lines and spaces across. ! 1+3+5+7+9=25 In a fraction of a second the scanner makes several calculations to determine the orientation of the code and then error checks to make certain that the scan was valid. ! ! It does this by testing an algorithm against the checksum digit.! 7
- 8. TESTING THE ALGORITHM 0+2+4+6+8=20 20x3=60 1+3+5+7+9=25 First the scanner sums the digits in the odd positions ! Then it multiplies that ! result by three! Next, it sums the even ! place digits ! 60+25=85 85/10=8R5 10-‐5=5 And adds the two sums! That result is divided by ten! The remainder is subtracted from ten to verify the checksum. If the checksum doesn’t match, the scanner reports an error and the code must be re-scanned.! 8
- 9. 2D BAR CODE / DATA MATRIX Two dimensional bar codes are called so because the reader scans both horizontally and vertically across the symbol, unlike linear barcodes. 9
- 10. HOW THEY ARE COMMONLY USED Along with the less popular PDF417 (actually stacked linear) and Aztec symbologies, Data Matrix is commonly used in healthcare. Because of its accuracy, efficiency and small size, it works particularly well on patient wristbands and medication labels, as it is less likely to distort around curves and takes up less space, in addition to being highly readable and accurate. 10
- 11. 2D symbologies, like Data Matrix, provide a consistent and reliable means of labeling small objects. 11
- 12. THE ANATOMY OF A DATA MATRIX TIMING PATTERN QUIET ZONE MODULE DATA REGION FINDER PATTERN 12
- 13. DATA MATRIX BAR CODE GLOSSARY MODULES: Small square cells that make up the bar code symbol. Usually, dark modules represent a digital 1 and light represent 0. FINDER PATTERN: Two adjacent, solid borders are designated the finder pattern. These borders are used by the scanner to locate and orient the symbol and to correct distortion. TIMING PATTERN: Two opposite adjacent pair of borders are constructed with alternating dark and light cells and are designated as the timing pattern. This component gives the scanner information about the symbol’s size. DATA REGION: The actual data and error correction information is divided into regions in the symbol which contain a pattern of modules in a consistent array. QUIET ZONE: A clear space around the symbol. 13
- 14. BENEFITS OF THE DATA MATRIX VERY EFFICIENT: Misread probability of 1/10.5 million (for the 3 of 9 symbol the probability drops to 1/1.7 million). SMALL: Almost 40X smaller than a 3 of 9 carrying the same data. DEPENDABLE: Error correction capabilities (ECC200 method) allows accurate reads on symbols with up to 60% damage. FAXABLE: Data Matrix is also one of the few codes that are faxable. The outstanding capabilities of ECC200 error correction allows even poorly resolved faxed images to be reliably scanned. STORAGE CAPACITY: They are designed to encode up to 2335 alphanumeric characters, though they have a recommended limit of 800 characters, actual best case is around 1200. 14
- 15. QR CODE The Quick Response or QR code is a trademarked two-dimensional barcode first designed for the automotive industry in Japan in 1994 by Denso Wave, a Toyota subsidiary. Almost a decade ago, it was introduced to enable high-speed component scanning during the manufacturing process. 15
- 16. HOW THEY ARE COMMONLY USED Since then QR codes have become ubiquitous, showing up on product packaging, billboards and bumper stickers, in magazines and just about any place where a consumer with a smartphone is likely to seek more information about any topic, item or idea. 16
- 17. THE ANATOMY OF A QR CODE TIMING PATTERN MODULES ENCODING PORTION ALIGNMENT PATTERN FINDER PATTERN 17
- 18. QR CODE GLOSSARY MODULES: square modules arranged on a grid. These modules form the components of the code. Within the code the modules fall into two categories: functional and encoding. FUNCTIONAL MODULES: referring to those pieces that enable accessing the data ENCODING MODULES: pieces used to store actual data FINDER PATTERN: These are made up of alternating black and empty modules used to indicate the position of the symbol’s internal components. ALIGNMENT PATTERNS: looking much like smaller versions of the positional detection indicators may occur in several places in the code depending on the code version. ENCODING PORTION: consists of the information formatting areas and the data and error correction space. QUIET ZONE: A clear space around the symbol 18
- 19. HOW IT ALL WORKS Data is divided up into code blocks within the data area, and each code block is sized so that it can contain no more than 15 errors. This strategy simplifies the algorithm, and interleaving the data in the code blocks minimizes the possibility of an unreadable code due to partial damage to symbol. This also allows for some artistic license with adding logos and other simple graphics to QR Codes. QR Codes can contain four basic types of information: numeric, alphanumeric, binary and Kanji. The key to the success of QR Codes lies in the use of Reed-Solomon error correction. 19
- 20. The QR Code bridges the gap between the physical and virtual worlds. 20
- 21. About NEPS: NEPS is a Business-Process-Automation Software and Services company. We deliver the technology platform and services for personalized communications between our clients and their customers with data-driven hosted and installed software solutions. Our mission-critical business solutions operate in highly complex, data-intensive, regulated environments for the financial services, insurance, healthcare and other select industries. © NEPS, LLC. All rights reserved. Contact NEPS: www.neps.com @nepsllc (866)636-6377 21