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== See also ==
 
== See also ==
* [[Automated identification and data capture]] (AIDC)
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* Michael Jackson
 
* [[Barcode printer]]
 
* [[Barcode printer]]
 
* [[Barcode scanner]]
 
* [[Barcode scanner]]

Revision as of 17:19, 17 September 2009

A UPC-A barcode symbol.

A barcode (also bar code) is an optical machine-readable representation of data. Originally, bar codes represented data in the widths (lines) and the spacings of parallel lines, and may be referred to as linear or 1D (1 dimensional) barcodes or symbologies. They also come in patterns of squares, dots, hexagons and other geometric patterns within images termed 2D (2 dimensional) matrix codes or symbologies. Although 2D systems use symbols other than bars, they are generally referred to as barcodes as well.

The first use of barcodes was to label railroad cars, but they were not commercially successful until they were used to automate supermarket checkout systems, a task in which they have become almost universal. Their use has spread to many other roles as well, tasks that are generically referred to as Auto ID Data Capture (AIDC). Other systems are attempting to make inroads in the AIDC market, but the simplicity, universality and low cost of barcodes has limited the role of these other systems. It costs about US$0.005 to implement a barcode compared to passive RFID which still costs about US$0.07 to US$0.30 per tag.[1]

Barcodes can be read by optical scanners called barcode readers, or scanned from an image by special software. In Japan most mobile phones have built-in scanning software for 2D codes, and similar software is becoming available on smartphone platforms.

History

In 1932 business student Wallace Flint of the Harvard University Graduate School of Business Administration wrote a thesis promoting an "automated grocery store" using punch cards, which customers would hand to a clerk, who would load them into a reader, causing flow racks to deliver the desired products, after which an itemized bill would automatically be produced.[2] In spite of its promise, punch card systems were expensive, and the country was in the midst of the Great Depression, and the idea was never implemented.

In 1948 Bernard Silver (1924–62), a graduate student at Drexel Institute of Technology in Philadelphia, overheard the president of a local food chain asking one of the deans to research a system to automatically read product information during checkout. Silver told his friends Norman Joseph Woodland (1921-) and Jordin Johanson about the request, and the three started working on a variety of systems. Their first working system used ultraviolet ink, but this proved to fade and was fairly expensive.[2]

Convinced that the system was workable with further development, Woodland quit his position at Drexel, moved into his father's apartment in Florida, and continued working on the system. His next inspiration came from Morse code, and he formed his first barcode from sand on the beach when "I just extended the dots and dashes downwards and made narrow lines and wide lines out of them."[2] To read them, he adapted technology from optical soundtracks in movies, using a 500-watt light bulb shining through the paper onto an RCA935 photomultiplier tube (from a movie projector) on the far side. He later decided that the system would work better if it were printed as a circle instead of a line, allowing it to be scanned in any direction.

On 20 October 1949 they filed a patent application for "Classifying Apparatus and Method", in which they described both the linear and bullseye printing patterns, as well as the mechanical and electronic systems needed to read the code. The patent was issued on 7 October 1952 as US Patent 2,612,994. In 1951 Woodland and Johanson moved to IBM and continually tried to interest IBM in developing the system. The company eventually commissioned a report on the idea, which concluded that it was both feasible and interesting, but that processing the resulting information would require equipment that was some time off in the future.

In 1952 Philco purchased their patent, and then sold it to RCA the same year. In 1962 Silver died in an automobile accident.

Collins at Sylvania

During his undergraduate degree, David Collins worked at the Pennsylvania Railroad and became aware of the need to automatically identify train cars. Immediately after receiving his master's degree from MIT in 1959, he started work at Sylvania and began addressing the problem. He developed a system using blue and yellow reflective stripes attached to the side of the cars, encoding a six-digit company identifier and a four-digit car number. Light reflected off the stripes was fed into one of two photomultipliers, filtered for blue or yellow.

The Boston and Maine Railroad tested the system on their gravel cars in 1961. The tests continued until 1967, when the Association of American Railroads (AAR) selected it as a standard across the entire North American fleet. The installations began on October 10, 1967. However, the economic downturn and rash of bankruptcies in the industry in the early 1970s greatly slowed the rollout, and it wasn't until 1974 that 95% of the fleet was labeled. To add to its woes, the system was found to be easily fooled by dirt in certain applications, and the accuracy was greatly affected. The AAR abandoned the system in the late 1970s, and it was not until the mid-1980s that they introduced a similar system, this time based on radio tags.

The railway project had proven to be a bust, but a toll bridge in New Jersey requested that a similar system be developed so that it could quickly scan for cars that had paid for a monthly pass. Then the U.S. Post Office requested the development of a system to keep track of the trucks entering and leaving their facilities. These applications required special retroreflective labels. Finally, Kal Kan asked the Sylvania team to develop a simpler (and cheaper) version which they could put on cases of pet food for inventory control. This, in turn, led to the grocery industry's interest.

Computer Identics

In 1967, with the railway system maturing, Collins went to management looking for funding for a project to develop a black and white version of the code for other industries. They declined, saying that the railway project was large enough and they saw no need to branch out so quickly.

Collins then quit Sylvania and formed Computer Identics. Computer Identics started working with helium-neon lasers in place of light bulbs, scanning with a mirror to locate the barcode anywhere up to several feet in front of the scanner. This made the entire process much simpler and more reliable, as well as allowing it to deal with ripped codes by reading the intact portions.

Computer Identics installed their first two systems in early 1969, one at a General Motors factory in Pontiac, Michigan, and another at a distribution center at the General Trading Company in Carlstadt, New Jersey[citation needed]. The General Motors system was used to identify car axles in inventory among the 18 models produced at the factory.

UPC

In 1966 the National Association of Food Chains (NAFC) held a meeting where they discussed the idea of using automated checkout systems. RCA, having purchased rights to the original Woodland patent, had attended the meeting and set up an internal project to develop a system based on the bullseye code. The Kroger grocery chain volunteered to test it.

In mid-1970, the NAFC established the U.S. Supermarket Ad Hoc Committee on a Uniform Grocery Product Code, which set guidelines for barcode development and created a symbol selection subcommittee to help standardize the approach. In cooperation with consulting firm McKinsey & Co., they developed a standardized 11-digit code to identify any product. The committee then sent out a contract tender to develop a system to print and read the code. The request went to Singer, National Cash Register (NCR), Litton Industries, RCA, Pitney-Bowes, IBM and many others.[3] A wide variety of barcode approaches were studied, including linear codes, RCA's bullseye concentric circle code, systems with starburst patterns, and even odder varieties.

In the spring of 1971 RCA demonstrated their bullseye code at another industry meeting, and IBM executives at the meeting noticed the crowds at the RCA booth, immediately setting out to develop their own system. IBM marketing specialist Alec Jablonover remembered that the company still employed the system's inventor Woodland, and he was set up in new facilities in North Carolina to lead the development.

In July 1972 RCA began an eighteen-month test of their system in a Kroger store in Cincinnati. Barcodes were printed on small pieces of adhesive paper, and attached by hand by store employees when they were adding price tags. The code proved to have a serious problem. During printing, presses sometimes smear ink in the direction the paper is running, rendering the code unreadable in most orientations. A linear code, like the one being developed by Woodland at IBM, however, was printed in the direction of the stripes, so extra ink simply makes the code "taller" while remaining readable, and on April 3, 1973 the IBM UPC code was selected by NAFC as their standard. IBM had designed five versions of the UPC symbology for future industry requirements — UPC A, B, C, D, and E [4]


NCR installed a testbed system at Marsh's Supermarket in Troy, Ohio, near the factory that was producing the equipment. On June 26, 1974, Clyde Dawson pulled a 10-pack of Wrigley's Juicy Fruit gum out of his basket and it was scanned by Sharon Buchanan at 8:01 am. The pack of gum and the receipt are now on display in the Smithsonian Institution. It was the first commercial appearance of the U.P.C.[5]

Economic studies conducted for the grocery industry committee projected over $40 million in savings to the industry from scanning by the mid-1970s. Those numbers were not achieved in that time frame and there were those who predicted the demise of barcode scanning. The usefulness of the barcode required the adoption of expensive scanners by a critical mass of retailers while manufacturers simultaneously adopted barcode labels. Neither wanted to move first and results weren't promising for the first couple of years, with Business Week proclaiming "The Supermarket Scanner That Failed."[5]

The Business Week writer failed to appreciate the patience and dedication being brought to the issue. For years many had worked to computerize the grocery industry. In 1971 IBM had assembled a team for an intensive planning session, day after day, 12 to 18 hours a day, to hash out how the whole system might operate and to schedule a rollout plan. By 1973 they were meeting with grocery manufacturers to introduce the symbol that would need to be printed on all of their products. There were no cost savings for a grocery to use it unless at least 70% of the grocery's products had the barcode printed on the product by the manufacturer. IBM was projecting that 75% would be in 1975. Even though that was achieved, there still were scanning machines in fewer than 200 groceries by 1977.[6]

Experience with barcode scanning in those stores revealed benefits previously unappreciated. The detailed sales information acquired by the new systems allowed far better servicing of customer needs. This was reflected in the fact that about 5 weeks after installing barcode scanners, sales in grocery stores typically started climbing and eventually leveled off at a 10 - 12% increase in sales that never dropped off. There also was a 1% to 2% decrease in operating cost for the stores that enabled them to lower prices in order to increase market share. It was shown in the field that the return on investment for a barcode scanner was 41.5%. By 1980 the technology was being adopted by 8000 stores per year.[6]

Industrial Adoption

In 1981 the United States Department of Defense adopted the use of Code 39 for marking all products sold to the United States military. This system, LOGMARS, is still used by DoD and is widely viewed as the catalyst for widespread adoption of barcoding in industrial applications.[7]

Use

Since the 20th century, barcodes — especially the UPC — have slowly become an essential part of modern civilization. Their use is widespread, and the technology behind barcodes is constantly improving. Some modern applications of barcodes include:

  • Almost every item purchased from a grocery store, department store, and mass merchandiser has a UPC barcode on it. This greatly helps in keeping track of a large number of items in a store and also reduces instances of shoplifting involving price tag swapping, although shoplifters can now print their own barcodes. Since the adoption of barcodes, both consumers and retailers have benefited from the savings generated.
  • Document Management tools often allow for barcoded sheets to facilitate the separation and indexing of documents that have been imaged in batch scanning applications.
  • The tracking of item movement, including rental cars, airline luggage, nuclear waste, mail and parcels.
  • Since 2005, airlines use an IATA-standard 2D barcode on boarding passes (BCBP), and since 2008 2D barcodes sent to mobile phones enable electronic boarding passes.[8]
  • Recently, researchers have placed tiny barcodes on individual bees to track the insects' mating habits.
  • Many tickets now have barcodes that need to be validated before allowing the holder to enter sports arenas, cinemas, theatres, fairgrounds, transportation etc.
  • Used on automobiles, can be located on front or back.
  • Joined with in-motion checkweighers to identify the item being weighed in a conveyor line for data collection
  • Some 2D barcodes embed a hyperlink to a web page. A capable cellphone might be used to read the barcode and browse the linked website.
  • In the 1970s and 1980s, software source code was occasionally encoded in a barcode and printed on paper. Cauzin Softstrip and Paperbyte[9] are barcode symbologies specifically designed for this application.
  • The 1991 Barcode Battler computer game system, which used any standard barcode to generate combat statistics.
  • 1992, Veterans Health Administration developed Bar Code Medication Administration system (BCMA).
  • At the turn of the century, many artists started using barcodes in art, such as Scott Blake's Barcode Jesus.

Symbologies

The mapping between messages and barcodes is called a symbology. The specification of a symbology includes the encoding of the single digits/characters of the message as well as the start and stop markers into bars and space, the size of the quiet zone required to be before and after the barcode as well as the computation of a checksum.

Linear symbologies can be classified mainly by two properties:

  • Continuous vs. discrete: Characters in continuous symbologies usually abut, with one character ending with a space and the next beginning with a bar, or vice versa. Characters in discrete symbologies begin and end with bars; the intercharacter space is ignored, as long as it is not wide enough to look like the code ends.
  • Two-width vs. many-width: Bars and spaces in two-width symbologies are wide or narrow; how wide a wide bar is exactly has no significance as long as the symbology requirements for wide bars are adhered to (usually two to three times wider than a narrow bar). Bars and spaces in many-width symbologies are all multiples of a basic width called the module; most such codes use four widths of 1, 2, 3 and 4 modules.

Some symbologies use interleaving. The first character is encoded using black bars of varying width. The second character is then encoded, by varying the width of the white spaces between these bars. Thus characters are encoded in pairs over the same section of the barcode. Interleaved 2 of 5 is an example of this.

Stacked symbologies consist of a given linear symbology repeated vertically in multiple.

There is a large variety of 2D symbologies. The most common are matrix codes, which feature square or dot-shaped modules arranged on a grid pattern. 2-D symbologies also come in a variety of other visual formats. Aside from circular patterns, there are several 2-D symbologies which employ steganography by hiding an array of different-sized or -shaped modules within a user-specified image (for example, DataGlyphs).

Scanner/symbology interaction

Linear symbologies are optimized to be read by a laser scanner, which sweeps a beam of light across the barcode in a straight line, reading a slice of the barcode light-dark patterns. In the 1990s development of CCD imagers to read barcodes was pioneered by Welch Allyn. Imaging does not require moving parts, like a laser scanner does. In 2007, linear imaging was surpassing laser scanning as the preferred scan engine for its performance and durability.

Stacked symbologies are also optimized for laser scanning, with the laser making multiple passes across the barcode.

2-D symbologies cannot be read by a laser as there is typically no sweep pattern that can encompass the entire symbol. They must be scanned by an image-based scanner employing a charge coupled device (CCD) or other digital camera sensor technology.

Scanners (barcode readers)

The earliest, and still the cheapest, barcode scanners are built from a fixed light and a single photosensor that is manually "scrubbed" across the barcode.

Barcode scanners can be classified into three categories based on their connection to the computer. The older type is the RS-232 barcode scanner. This type requires special programming for transferring the input data to the application program. Another type connects between a computer and its PS/2 or AT keyboard by the use of an adaptor cable. The third type is the USB barcode scanner, which is a more modern and more easily installed device than the RS-232 scanner. Like the keyboard interface scanner, this has the advantage that it does not need any code or program for transferring input data to the application program; when you scan the barcode its data is sent to the computer as if it had been typed on the keyboard.

Verifier (Pika inspection)

Barcode verifiers are primarily used by businesses that print barcodes, but any trading partner in the supply chain could test barcode quality. It is important to "grade" a barcode to ensure that any scanner in the supply chain can read the barcode. Retailers levy large fines and penalties for non-compliant barcodes.

Barcode verifiers work in a way similar to a scanner but instead of simply decoding a barcode, a verifier performs a series of eight tests. Each test is given a grade from 0.0 to 4.0 (F to A) and the lowest of any of the tests is the scan grade. For most applications a 2.5 (C) grade is the minimum acceptable grade.

Barcode Verifier Standards:

  • Barcode verifiers should comply with the ISO 15426-1 (linear barcode verifier compliance standard) or ISO 15426-2 (2d barcode verifier compliance standard)
  • The current international barcode quality specification is ISO/IEC 15416 (linear barcodes) and ISO/IEC 15415 (2D barcodes)
  • The European Standard EN 1635 has been withdrawn and replaced by ISO/IEC 15416
  • The original U.S. barcode quality specification was ANSI X3.182. UPC Codes used in the US ANSI/UCC5.

Barcode Verifier Manufacturers (partial list):

  • Auto ID Solutions (2D)
  • LVS(R)Inc ( linear, 2D)
  • Intermec (linear, 2D)
  • Motorola Symbol (2D, linear)
  • Axicon (linear and 2D)(www.axicon.com)
  • Code Corporation (linear and 2D)
  • Cognex Corporation (2D, UID)
  • Honeywell (earlier known as Metrologic and HHP) (linear and 2D)
  • REA Elektronik GmbH (linear)
  • RJS/Printronix (linear)
  • Microscan(UID, Data Matrix(2D), linear)
  • Stratix (linear)
  • Webscan (linear and 2D)
  • Datalogic (Linear, Stacked, 2D and direct part marked barcodes as well as signature capture.) (www.datalogic.com)

Barcode Verifier Test Code Manufacturers ((traceable reflectance and linear measure) used to check proper function of verifiers)

  • Applied Image Inc. (Rochester, NY, USA) (m)

Benefits

In point-of-sale management, the use of barcodes can provide very detailed up-to-date information on key aspects of the business, enabling decisions to be made much more quickly and with more confidence. For example:

  • Fast-selling items can be identified quickly and automatically reordered to meet consumer demand,
  • Slow-selling items can be identified, preventing a build-up of unwanted stock,
  • The effects of repositioning a given product within a store can be monitored, allowing fast-moving more profitable items to occupy the best space,
  • Historical data can be used to predict seasonal fluctuations very accurately.
  • Items may be repriced on the shelf to reflect both sale prices and price increases.

Besides sales and inventory tracking, barcodes are very useful in shipping/receiving/tracking.

  • When a manufacturer packs a box with any given item, a Unique Identifying Number (UID) can be assigned to the box.
  • A relational database can be created to relate the UID to relevant information about the box; such as order number, items packed, qty packed, final destination, etc…
  • The information can be transmitted through a communication system such as Electronic Data Interchange (EDI) so the retailer has the information about a shipment before it arrives.
  • Tracking results when shipments are sent to a Distribution Center (DC) before being forwarded to the final destination.
  • When the shipment gets to the final destination, the UID gets scanned, and the store knows where the order came from, what's inside the box, and how much to pay the manufacturer.

The reason barcodes are business-friendly is that the scanners are relatively low cost and extremely accurate compared to key-entry, with only about 1 substitution error in 15,000 to 36 trillion characters entered.[10] The exact error rate depends on the type of barcode.

Types of barcodes

Linear barcodes

Symbology Continous
or
discrete
Two
or
many
Uses
U.P.C. Continuous Many Worldwide retail, GS1 approved
Codabar Discrete Two Old format used in libraries, blood banks, airbills
Code 25 – Non-interleaved 2 of 5 Continuous Two Industrial (NO)
Code 25 – Interleaved 2 of 5 Continuous Two Wholesale, Libraries (NO)
Code 39 Discrete Two Various
Code 93 Continuous Many Various
Code 128 Continuous Many Various
Code 128A Continuous Many Various
Code 128B Continuous Many Various
Code 128C Continuous Many Various
Code 11 Discrete Two Telephones
CPC Binary Discrete Two Post office
DUN 14 Continuous Many Various
EAN 2 Continuous Many Addon code (Magazines), GS1 approved
EAN 5 Continuous Many Addon code (Books), GS1 approved
EAN 8, EAN 13 Continuous Many Worldwide retail, GS1 approved
Facing Identification Mark Continuous One USPS business reply mail
GS1-128 (formerly known as UCC/EAN-128), incorrectly referenced as EAN 128 and UCC 128 Continuous Many Various, GS1 approved
GS1 DataBar formerly Reduced Space Symbology (RSS) Continuous Many Various, GS1 approved
ITF-14 Continuous Many Non-retail packaging levels, GS1 approved
Latent image barcode Neither Tall/short Color print film
Pharmacode Neither Two Pharmaceutical Packaging
Plessey Continuous Two Catalogs, store shelves, inventory
PLANET Continuous Tall/short United States Postal Service
POSTNET Continuous Tall/short United States Postal Service
Intelligent Mail Barcode Continuous Tall/short United States Postal Service, replaces both POSTNET and PLANET symbols (Previously known as OneCode)
MSI Continuous Two Used for warehouse shelves and inventory
PostBar Discrete Many Post office
RM4SCC / KIX Continuous Tall/short Royal Mail / Royal TPG Post
JAN Continuous Many Used in Japan, similar and compatible with EAN-13
Telepen Continuous Two Libraries, etc (UK)

Matrix (2D) barcodes

A matrix code, also known as a 2D barcode or simply a 2D code, is a two-dimensional way of representing information. It is similar to a linear (1-dimensional) barcode, but has more data representation capability.

Symbology Notes
3-DI Developed by Lynn Ltd.
ArrayTag From ArrayTech Systems.
Aztec Code Designed by Andrew Longacre at Welch Allyn (now Hand Held Products). Public domain.
Small Aztec Code Space-saving version of Aztec code.
Chromatic Alphabet[11] an artistic proposal by C. C. Elian; divides the visible spectrum into 26 different wavelengths - hues.
Chromocode uses black, white, and 4 saturated colors.[12]
Codablock Stacked 1D barcodes.
Code 1 Public domain.
Code 16K Based on 1D Code 128.
Code 49 Stacked 1D barcodes from Intermec Corp.
ColorCode ColorZip[1] developed colour barcodes that can be read by camera phones from TV screens; mainly used in Korea.[13]
Compact Matrix Code From Syscan Group, Inc.
CP Code From CP Tron, Inc.
CyberCode From Sony.
d-touch readable when printed on deformable gloves and stretched and distorted[14]
DataGlyphs From Palo Alto Research Center (also known as Xerox PARC).[15]
Datamatrix From RVSI Acuity CiMatrix/Siemens. Public domain. Increasingly used throughout the United States.
Datastrip Code From Datastrip, Inc.
Dot Code A Designed for the unique identification of items.
EZcode Designed for decoding by cameraphones.[16]
Grid Matrix Code From Syscan Group, Inc.
High Capacity Color Barcode Developed by Microsoft; licensed by ISAN-IA.
HueCode From Robot Design Associates. Uses greyscale or colour.[17]
INTACTA.CODE From INTACTA Technologies, Inc.
InterCode From Iconlab, Inc. The standard 2D barcode in South Korea. All 3 South Korean mobile carriers put the scanner program of this code into their handsets to access mobile internet, as a default embedded program.
MaxiCode Used by United Parcel Service. Now Public Domain
mCode Developed by Nextcode Corporation specifically for camera phone scanning applications. Designed to enable advanced cell mobile applications with standard camera phones.
MiniCode From Omniplanar, Inc.
PDF417 Originated by Symbol Technologies. Public Domain.
Micro PDF417 Facilitates codes too small to be used in PDF417.
PDMark Developer by Ardaco.
PaperDisk High density code — used both for data heavy applications (10K-1 MB) and camera phones (50+ bits). Developed and patented by Cobblestone Software.[18]
Optar Developed by Twibright Labs and published as free software. Aims at maximum data storage density, for storing data on paper. 200kB per A4 page with laser printer.
QR Code Developed, patented and owned by TOYOTA subsidiary Denso Wave initially for car parts management. Now public domain. Can encode Japanese Kanji and Kana characters, music, images, URLs, emails. De-facto standard for Japanese cell phones.
QuickMark Code From SimpleAct Inc..
Semacode A Data Matrix code used to encode URLs for applications using cellular phones with cameras.
SmartCode From InfoImaging Technologies.
Snowflake Code From Marconi Data Systems, Inc.
ShotCode Circular barcodes for camera phones by OP3. Originally from High Energy Magic Ltd in name Spotcode. Before that probably known as TRIPCode.
SuperCode Public domain.
Trillcode From Lark Computers. Designed to work with mobile devices camera or webcam PC. Can encode a variety of "actions".
UltraCode Black-and-white & colour versions. Public domain. Invented by Jeffrey Kaufman and Clive Hohberger.
UnisCode also called "Beijing U Code"; a colour 2D barcode developed by Chinese company UNIS
VeriCode, VSCode From Veritec, Inc.
WaterCode High-density 2D Barcode(440 Bytes/cm2) From MarkAny Inc.

Example images

See also

References

  1. ^ Some Hot North American RFID Applications, RFID Radio
  2. ^ a b c Tony Seideman, "Barcodes Sweep the World", Wonders of Modern Technology
  3. ^ George Laurer, "Development of the U.P.C. Symbol"
  4. ^ Nelson, Benjamin (1997). "From Punched Cards To Bar Codes". 
  5. ^ a b Varchaver, Nicholas (2004-05-31). "Scanning the Globe". Fortune. Retrieved 2006-11-27.  Check date values in: |date= (help)
  6. ^ a b Selmeier, Bill (2008). Spreading the Barcode. pp. 26, 214, 236, 238, 244, 245, 236, 238, 244, 245. ISBN 978-0-578-02417-2. 
  7. ^ http://www.adams1.com/history.html
  8. ^ IATA
  9. ^ "Paperbyte Bar Codes for Waduzitdo" Byte magazine, 1978 September p. 172
  10. ^ Harmon and Adams(1989). Reading Between The Lines, p.13. Helmers Publishing, Inc, Peterborough, NH. ISBN 0911261001.
  11. ^ Chromatic Alphabet by C. C. Elian. The Elian Script
  12. ^ Chromocode ... Multicolor / Polychromatic Barcode Symbology
  13. ^ ""Barcodes for TV Commercials"". Adverlab.blogspot.com. 2006-01-31. Retrieved 2009-06-10. 
  14. ^ d-touch topological fiducial recognition; "d-touch markers are applied to deformable gloves"
  15. ^ See http://www.xerox.com/Static_HTML/xsis/dataglph.htm for details.
  16. ^ scanbuy.com
  17. ^ "BarCode-1 2-Dimensional Bar Code Page". Adams1.com. Retrieved 2009-06-10. 
  18. ^ PaperDisk
  19. ^ (株)デンソーウェーブ (in Japanese) Copyright

Further reading

  • Automating Management Information Systems: Barcode Engineering and Implementation – Harry E. Burke, Thomson Learning, ISBN 0-442-20712-3
  • Automating Management Information Systems: Principles of Barcode Applications – Harry E. Burke, Thomson Learning, ISBN 0-442-20667-4
  • The Bar Code Book – Roger C. Palmer, Helmers Publishing, ISBN 0-911261-09-5, 386 pages
  • The Bar Code Manual – Eugene F. Brighan, Thompson Learning, ISBN 0-03-016173-8
  • Handbook of Bar Coding Systems – Harry E. Burke, Van Nostrand Reinhold Company, ISBN 978-0-442-21430-2, 219 pages
  • Information Technology for Retail:Automatic Identification & Data Capture Systems - Girdhar Joshi, Oxford University Press, ISBN 0-19-569796-0, 416 pages
  • Lines of Communication – Craig K. Harmon, Helmers Publishing, ISBN 0-911261-07-9, 425 pages
  • Punched Cards to Bar Codes – Benjamin Nelson, Helmers Publishing, ISBN 0-911261-12-5, 434 pages
  • Revolution at the Checkout Counter: The Explosion of the Bar Code – Stephen A. Brown, Harvard Univ Press, ISBN 0-674-76720-9
  • Reading Between The Lines – Craig K. Harmon and Russ Adams, Helmers Publishing, ISBN 0-911261-00-1, 297 pages
  • The Black and White Solution: Bar Code and the IBM PC – Russ Adams and Joyce Lane, Helmers Publishing, ISBN 0-911261-01-X, 169 pages
  • Sourcebook of Automatic Identification and Data Collection – Russ Adams, Van Nostrand Reinhold, ISBN 0-442-31850-2, 298 pages

External links