barcode guide
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Barcode Guide. Bar Codes and Variable Data. Unlimited Applications Inventory Control Sorting, Tracking Verification Quality Control Automated Warehousing Shop Floor Control Product Identification Addressing. What is a Bar Code?. A Pattern of dark and light areas - PowerPoint PPT PresentationTRANSCRIPT
Barcode Guide
Bar Codes and Variable Data
Unlimited Applications– Inventory Control– Sorting, Tracking– Verification– Quality Control– Automated Warehousing– Shop Floor Control– Product Identification– Addressing
What is a Bar Code?
A Pattern of dark and light areas– Can be bars (Linear) or cells (2D)
The pattern represents the encoded information
May contain letters, numbers, characters or a mix
Why use a Bar Code?
Accurate Eliminate data entry errors
– Errors due to bar codes: less than 0.001%– Coded information errors: 1 every 10,000,000
characters– Manual information errors: 1 every 100
characters Fast
– Read and decode infinitely faster than manually
Easy and cheap to produce
Bar Code Terminology
Bars and Spaces– The elements of the bar code. Made up of
narrow and wide lines Human Readable
– The ASCII interpretation of the coded information
– Can be printed near the bar code for verification
Quiet Zone– Clear area before and after the printed code– Allows scanner to “calibrate” to the image
Bar Code Terminology
– Quiet zone is required to read data– Minimum quiet zone can vary with different
symbology
Discrete Bar Code– Unique pattern for each character. Can be
manually decoded
Bar Code Terminology
Continuous Bar Code– Bar patterns overlap. Each character’s symbol
relates to the ones around it– Can not be easily manually decoded
Bar Code Terminology
Check Digit– Confirms integrity of the encoded and decoded
data– A formula uses the bar code data to generate a
digit which is then added to the encoded information
– The reader calculates a check digit based on what is decoded and compares this number to the encoded number
Bar Code Terminology
Aspect Ratio– The ratio of Bar Height to Symbol Length
Code Density– Number of data characters which can be
encoded in a linear inch (characters/inch)
Message Overhead– Space occupied by start, stop and check digit
symbols. Increase the size of the barcode
Bar Code Terminology
Bar Width– Thickness of bar measured from the edge
closest to the start character to the edge farthest from the start character
Bar Length (Bar Height)– Dimension perpendicular to the bar width
Bi-Directional– Symbol type has no defined read direction– Can be decoded in either direction
Bar Code Terminology
Character– A single group of bars and spaces
representing a single element of data– A graphic shape representing a letter, numeral
or symbol
Character Set– Group of valid symbols which can be encoded
in a given bar code type
Bar Code Terminology
Data Identifier– Message prefixes, conforming to standards
that are incorporated in a bar code that define the category or use of the data that follows
Decoder– A device that uses algorithms to interpret the
signals set by the scanner and generate meaningful data
Scanner– A device that reads the bar code
Bar Code Terminology
Depth of field– The distance between the minimum and
maximum read distance from the scanner to the bar code
EAN– European Article Numbering System– International standard for product coding
UPC– Universal Product Code– U.S. standard for retail package coding
Bar Code Terminology
First Read Rate– Percentage of correct readings obtained in one
pass of the scanner
Fixed Beam Scanner– Scanner reading in a fixed plane– Requires more precise code placement
Rastering Scanner– Scan line sweeps along the bar height– Code placement does not need to be as
precise
Horizontal Bar Code (Picket Fence)– Bars are presented so the bar length is in the
direction of travel
Vertical Bar Code (Ladder, Rotated)– Bars are presented so the bar width is in the
direction of travel
Bar Code Terminology
Bar Code Terminology
Inter Character Gap– The space between two adjacent characters in
a discrete bar code
Interleaved Bar Code– Characters are paired together using bars to
represent the first character and spaces to represent the second
– Increases bar code density
Misread– Output of reader does not match encoded data
Bar Code Terminology
No-Read– Absence of scanner output due to no code,
defective code, scanner failure or operator error
OCR-A and -B– Character font set used in Optical Character
Recognition and automatic identification– Both human and machine readable– Defined by ANSI standards
Bar Code Terminology
Optical Throw– Minimum distance from the scanner to the
code for successful reading
Read Rate– Ratio of successful first scan reads to the total
number of read attempts
Reflectance– The light reflected by the white spaces– This is what the scanner actually reads
Bar Code Terminology
Resolution– The narrowest element division which can be
distinguished by a particular scanner
Self Checking– A code that uses a checking algorithm which
can be independently applied to each character to guard against errors
Error Checking & Correction (ECC)– A self checking code whose algorithm can fix
errors in the encoding or decoding of data
Bar Code Terminology
Space– Light element of a bar code– Usually formed by the substrate
Stacked Code– Long symbol is broken into sections and
stacked on itself similar to sentences in a paragraph
– Code 49 and 16K are examples of this type
Bar Code Terminology
Start-Stop Character– A special character which helps the scanner
decode the symbol– Start character is normally at the left end of a
horizontally oriented symbol, the stop is normally at the right
ISBN – International Standard Book Number– Unique number to identify books, audio and
video products and software
Bar Code Terminology
ISSN – International Standard Serial Number– Unique number to identify serial publications
such as magazines, newspapers, etc.
Selecting A Bar Code
Amount and Type of Characters encoded Quality Available Space Industry Standards How and by whom it will be decoded
– Linear codes can be read by a simple scanner– 2D codes may require a more expensive
imager
Linear Symbologies
Pros– Well established, common codes– Numerous different formats to choose from– Fast and inexpensive reading and decoding– Can include human readable interpretation
Cons– Limited data capacity– Can be space prohibitive– Type of data encoded can be limited by symbol
UPC
Universal Product Code First widely accepted bar code symbol Now a subset of the EAN symbology Fixed in length Numbers only Continuous symbol with four element
widths Number is unique and is registered to a
particular product and packaging
UPC-A
10 digits and two overhead digits First overhead digit is the type of product Second overhead digit is the check digit 5 digits identify the manufacturer, 5
identify the product
UPC-E
Similar to UPC-A Zero digits are dropped, making the code
smaller
Other UPC
UPC-B– 11 digits + 1 Overhead, no check digit
UPC-C– 12 digits + 2 Overhead
UPC-D– Variable length– At least 10 digits + 2 Overhead
EAN
European Article Numbering Code 8 and 13 are similar to UPC codes with the
addition of “Flag” digits Flag digits identify the country where the
product identification number was issued Flag digits do not determine where the
product is manufactured
EAN-8
Two Flag digits, five data digits and 1 check digit
EAN-13
Most common EAN symbol Identical to UPC-A except for Flag Digit
Supplementals
UPC and EAN 8 and 13 can have a supplemental bar code attached to carry additional information
EAN13+5
UPC-A+5
UPC-E+5
EAN-128
Extremely versatile symbol for package ID Application Identifiers determine the
purpose of the data following (Serial Number, Weight, Box Dimensions, etc.)
Same as Code 128 except for the addition of Identifiers
Code 128
General purpose alphanumeric and extended ASCII
Reference symbology for UCC Serial Shipping Container Symbol
Same as EAN-128 without Application Identifiers
Codabar
All numeric data Four unique stop/start characters to
convey additional information Optional check digit
Code 39
Most used symbol for inventory and shipping
Alphanumeric data set Extended Code 39 allows upper and lower
case characters and punctuation Most popular symbol outside of retail
(UPC) industry
Interleaved 2 of 5 (ITF)
Mainly used in the distribution industry for coding corrugated cartons
Numeric only Must be an even number of digits Continuous bar code, characters overlap
ITF-14
UPC Shipping Container Symbol Used on cartons, cases or pallets of UPC
or EAN coded products 14 digit ITF symbol Indicates the package type, quantity in
carton and UPC of packaged item
Pharmacode
Security Verification System for Pharmaceutical Industry– Insures that leaflet, label, container, carton,
contents and other packing materials match and are correct
Postnet
Used by the US Postal Service to sort mail Evenly spaced bars of two different
heights Contains a 5 (zip), 9 (zip+4), or 11 (delivery
point code) digit routing code
2D Stacked Symbologies
Pros– More data in the same amount of space as
linear codes
Cons– Still require larger area for the code– Require an imager or rastering scanner for
reading– Human readable interpretation is not available
Code 49
High information density of full ASCII set
Code 16K
High information density of full ASCII set Double density encoding of numeric data Capable of handing extended ASCII
PDF417
Easily decoded by CCD or laser scanner Selectable levels of error correction Able to encode extended ASCII set Thousands of characters capacity
Micro PDF417
Similar to PDF417 Smaller data capacity than PDF417 Limited set of symbol sizes and error
correction levels
2D Matrix Symbologies
Pros– Extremely small area for amount of data
encoded– Unobtrusive on most products adds aesthetic
values for consumer products
Cons– Expensive imaging scanners required– Can be slower to decode– Error correction and detection is essential due
to the complexity of the code
3-DI
Proprietary Code Suited for shiny, curved metal surfaces
Array Tag
Proprietary Code Can be read at distances up to 50 meters Primary use is for logs and lumber
DataGlyphs
Proprietary Code Tolerant to ink marks, bad copies, staples
etc. Can be used as a logo or tint behind text
or graphics
Dot Code A (Philips Dot Code)
Designed for low precision marking systems
Up to 12x12 matrix allows up to 42 billion, billion, billion, billion (a big number) individual items to be uniquely coded
Used on laboratory glassware and laundry
MaxiCode
Originally called UPSCode About 100 characters in a 1”x1” square Can still be read with up to 25% of the
code destroyed Primarily used by United Parcel Service
MiniCode
Proprietary code Patented method of encoding low
resolution (tracking/sortation) and high resolution (manifest information) data
Data Matrix ECC 200
Up to 3116 characters in a 144x144 matrix High density, very small code Very easy to scan under a variety of
conditions Being adopted as standard in a variety of
industry groups
Aztec Code
Public Domain 12 - 3832 characters, 15x15 – 151x151 Easy printing and decoding
QR Code
Quick Response Code Public Domain code Up to 7366 characters Capable of handling Japanese Kanji and
Kana characters
Snowflake
Owned by Videojet Proprietary, pay per use code
Composite Bar Codes
Two Symbols Printed in close proximity Data is linked between the two Typically one linear and one stacked or
matrix symbol Used in applications that require different
parts of data to be used at different times
Bar Code Quick Reference
Barcode Type Character Set Length Checksum Applications/Comments
EAN-13 Linear Numbers Only12 data digits and 1 check digit; 2 or 5 digit supplement optional Required Retail product marking world-wide
EAN-8 Linear Numbers Only RequiredRetail product marking world-wide; compressed code for products with limited label space
EAN Bookland Linear Numbers Only RequiredSpecial use of the EAN-13 symbol to encode ISBN number on books
UPC-A Linear Numbers Only11 data digits and 1 check digit; 2 or 5 digit supplemental optional Required Retail product marking in USA and Canada
UPC-E Linear Numbers Only RequiredRetail product in USA and Canada; compressed code for products with limited label space
UPC Shipping Container Code
Special use of the Interleaved 2 of 5 code to mark shipping cartons containing UPC encoded products
(ITF-14) (see also SCC-14)UCC/EAN Shipping Container Code
Special use of Code 128 to mark shipping cartons containing UPC encoded products
(SCC-14) (see also ITF-14)1 Required;2 Recommended
Interleaved 2 of 5 Linear Numbers Only Variable OptionalVery compact encodes digits in pairs so total length must be even number of digits
Industrial 2 of 5 Linear Numbers Only Variable None defined Older type of codeStandard 2 of 5 Linear Numbers Only Variable None defined Older type of codeCodabar Numbers: 0-9;(USD-4, NW-7, 2 of 7) Symbols: - : . $ / +
Start/Stop Characters: A, B, C, D, E, *, N, or T
Plessey Linear Numbers Only Variable Required Grocery store shelf tagsLinear Variable None defined Older code; often used in libraries and blood banks
Code 11 Linear Numbers Only Variable
Linear Numbers Only 13 digits and 1 check digit Required
Linear Numbers Only 13 data digits and 1 check digit Required
Bar Code Quick Reference (Cont.)
OPC(Optical Industry Association)
Bar Height USA postal codeEncoding (ZIP code)
Uppercase letters A-Z;Numbers 0-9;Space - . $ / + %Uppercase letters A-Z;Numbers 0-9;Space - . $ / + %
Extended Code 39 LinearAll ASCII characters and control codes Variable Optional
Uses pairs of characters to encode non-standard symbols; wasteful of space
Code 128 LinearAll ASCII characters and control codes Variable Required Widely used; excellent for many applications
UCC/EAN-128 LinearAll ASCII characters and control codes Variable Required
Special ise of Code 128 which defines data formats for commerce
Uppercase letters A-Z;Numbers 0-9;Space - . $ / + %
PDF-417 2-D All ASCII charactersVariable, up to about 1850 ASCII or 2725 numeric characters Error correction
DataMatrix 2-D All ASCII charactersVariable, up to 2335 ASCII characters Error correction
Maxicode 2-D All ASCII characters 93 ASCII characters Error correctionDeveloped by the United Parcel Service for encoding parcel destination information for auto-sorting
QR Code 2-D All ASCII CharactersVariable, up to about 1520 ASCII or 2509 numeric charcters Error correction
LOGMARS
In very wide use for many types of applications
Code 93 Linear Variable OptionalA more compact cousin of Code 39, not as widely in use
Code 39 Linear Variable Optional
Special use of Interleaved 2 of 5 for marking retail optical products
Postnet Numbers Only 5, 9, or 11 digits and 1 check digit Required
Linear Numbers Only 9 data digits and 1 check digit Required
Linear Variable OptionalSame as Code 39; this is the US government specification