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Code Readers / OCR

Code Readers can read 2D codes or bar codes and are available in installed or hand-held models.

Introduction Features
Principles Classifications
Engineering Data Further Information
Explanation of Terms Troubleshooting

Related Contents

Primary Contents



What Is a Barcode?

According to the definition by ANSI (American National Standards Institute), a barcode is a display of information in the form of bars (black portions) and spaces (area between the bars) of varying widths.
Barcodes first emerged in the 1970s, and have come to be employed in a variety of different industries and applications, beginning with the fields of distribution and logistics.
There are a number of varieties of barcodes such as the JAN/EAN codes, CODE128 which are used to manage barcodes for POS, and CODE39 which is used extensively in the industrial field ,and NW-7 which is used in distribution. These barcodes are all governed by ISO/IEC international standards.
When the quality of the barcode printing is not good, the data may be read incorrectly, so it is important to take care in printing labels etc.

Features of Barcodes

Highly flexibility due to its widespread use internationally

Indespensible identification system for international transport, POS, etc.

High Speed Processing

An effective tool for classification processes in high speed production lines etc.

Great variety of models

There are a variety of different readers, including the Pen model, Handy model, Stationary model, CCD model, laser model and camera model etc.

Visible Information

By printing characters in addition to the barcode, it is possible to confirm information just by looking at it.

Major Types and Application of Barcodes

TypePatternCharactersApplicationInternational
standards
JAN/EAN
NumbersPOS BarcodesISO/IEC15420
CODE39
Numbers, alphabet,
partially used symbols
Widely used in
industries
ISO/IEC16388
Codabar
(NW-7)
Numbers,
Stop codes (A to D)
Symbols (-,+,$,;,/,.)
Membership cards
for blood bank
management, parcel
delivery, libraries
ISO/IEC16390
ITF
Numbers,
Stop codes (A to D)
Symbols (-,+,$,;,/,.)
Membership cards
for blood bank
management, parcel
delivery, libraries
ISO/IEC15390
CODE128
All ASCII 128
characters
Auxiliary BarcodesISO/IEC15417

* Also STF, CODE93, in addition to those above.

Structure of Barcode Label (Example)

What Is a 2 Dimensional Code?

Barcodes require a great deal of space to express a lot of information, which means that they are difficult to use on small items and for stock control. For example, in the case of small goods for cell phones, these are generally in such high density packaging that barcode labels won't even fit. Also, since barcodes become difficult to read if they are dirty or damaged, a great deal of care need to be taken to maintain the quality of the printing.
In order to solve these problems, the 2 dimensional code was developed which by expressing information in 2 dimensions, makes it possible to include a lot of information at high density in a small space, and can be read even where the print quality is low or it is dirty. Information management including traceability of all the items is ensured by the fact that the 2 dimensional codes are applied directly to goods and products using direct marking by means of a laser marker etc. In addition, for 2 dimensional codes as well, ISO/IEC international standards have progressed to the point where they are now applicable globally.

Features of 2 Dimensional Codes

Very high information density in comparison to barcodes

The same information can be expressed with 1/10~1/100 as much density as the barcode.

Marking in extremely small spaces which was impossible with barcodes is possible.

Large amount of information

7 KB of information can be held, expressing approx. 7000 characters in number form.

Kanji can also be used, making it possible to use as a portable data file.

Information can be printed directly onto items

Direct marking on an item by using a laser enables realizing unite items with their information".

High flexibility in the angle and direction of reading

Using a 2 dimensional CCD scanner enables reading data from 360 degrees.

Since there are no limits on the direction for reading 2 dimensional code, work efficiency can be increased.

Protected against dirt and scratches due to error correction functions

If a code is dirty or damaged, there are functions to restore
data from the readable data available, but this is only possible depending on the restoration level setting. As such, in contrast to barcodes, there are no erroneous
readings.

The error correction level can be set at the time of encoding, and a code can be restored from more than 1/2 of the damaged code at its ultimate level.

Major Types of 2 Dimensional Codes

TypeFormFeaturesError correction
rate/(error)
restoration rates
International
standards
Reader
Data Matrix
L-shaped profile pattern
and diagonal timing pattern
Allows symbols
to be made
compact
Data structures of older
version and ECC200 are
different. ECC200 has a
30% error correction rate.
ISO/IEC16022CCD
Image
Reader
QR Code
Three profile smbols
Enables high-
speed reading,
and is not
affected by
direction
Four selectable correction
rates; 7%, 15%, 25% and
30%.
ISO/IEC18004
QR Code
Concentric circles
in center
Data structure
enables high-
speed profile
Primary message; 25%
Secondary message:
Standard Level SEC (15%)
Extended Level EEC (21%)
ISO/IEC16023
PDF417
Stack Format
Suitable for large
data volumes,
readable by laser
scanners
Contains seven
correction levels
ISO/IEC15438Laser
Scanner
CCD
Image
Reader

Structure of 2 Dimensional Code (Example)