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IDAutomation Barcode FAQ and Tutorial
The industrial use of barcodes can be traced back as far as the 1960s, in some cases as a means to identify railroad cars. Common linear barcodes started appearing on grocery shelves in the early 1970s as the UPC barcode to automate the process of identifying grocery items. Today, barcodes are just about everywhere and are used for identification in almost all fields of business. When barcode technology is utilized in business processes, procedures are automated to increase productivity and reduce human error. Barcoding should be used whenever there is a need to accurately identify or track something.
Radio Frequency Identification (RFID) is still in its infancy as a technology, and implementation is usually many times more expensive compared to that of barcoding. There are many additional issues to consider with RFID such as those listed in the Disadvantages of RFID section in IDAutomation's RFID FAQ. However, RFID also has many advantages over barcoding. In some cases, these advantages outweigh the disadvantages and high cost of implementing RFID technology. Decision makers must carefully consider whether RFID really provides an advantage the traditional use of barcodes in their business model.
The type of barcode that should be used may depend on several variables, including the following:
There are several different types of barcode standards for different purposes - these are called symbologies. Each type of symbology (or barcode type) is a standard that defines the printed symbol and how a device, such as a barcode scanner, reads and decodes the printed symbol. If an industry standard has already been established for the intended implementation, the standard should be implemented. If a standard does not exist for the chosen implementation, several symbologies are available to choose from. Industry standards are usually established when multiple parties or companies are involved in the ID process. The standard is not necessarily the same as the barcode symbology. Barcode standards define how to use the barcode symbology in a particular situation. For example, ISBN is a standard for labeling books and periodicals that uses the EAN-13 symbology. The chart below includes a few established barcode standards and what they are used for: Established Barcode Standards:
IDAutomation also offers a list of several popular barcode symbologies at the barcode FAQ site and information about how to identify the various symbologies.
IDAutomation offers several Application Integration Guides that suggest one or more options for integrating barcodes. The integration options should be examined to determine whether to implement components, applications or barcode fonts for printing. A few of the Barcode Integration Guides offered include the following:
Once it is determined which product to use for the printing of barcodes, the following suggestions may help in selecting the barcode symbology: When using Barcode Components or Applications for printing, the following is suggested:
When using Barcode Fonts, the following is suggested:
When barcodes are sent via fax machine or are used in a low-resolution environment, the following is suggested:
When Barcode Applications are used, the following is suggested:
When encoding photos, arrays, binary data, Unicode, international or double-byte characters, the following is suggested: A two-dimensional symbology (2D barcode) such as the PDF417 or Data Matrix barcode should be used to encode this type of data. 2D barcodes encode this type of data when the encoding mode is set to BASE256 or BINARY, which encodes all data, byte-by-byte. When scanning the data, the barcode scanner must be able to read all 256 bits of each byte. This usually means using the serial interface option (data bits have to be 8N) on the scanner, serial emulation over USB or another type of connection that allows all 256 bits of each byte to be transferred to the necessary application. Normally, keyboard wedge and USB barcode scanners (that emulate a keyboard) do not support extended characters above ASCII 128, and they only read characters that are actually on the keyboard. The scanner manual or vendor may need to be consulted for this type of implementation. Alternatively, the data may be converted to Base64 when encoded in the barcode and then back again when read. However, this requires additional programming and will create a symbol that is about four times larger then it would be with BASE256 or BINARY encoding. When creating PDF documents, the following is suggested: IDAutomation barcode fonts may be used to integrate barcodes
into PDF documents, thus creating virus-free portable data files
that can be viewed on all operating systems with a PDF viewer. The
fonts have been tested and work with the following PDF conversion
products:
One of the most common tools for reading barcodes is the
hand-held barcode
scanner. The
barcode scanners recommended and sold by IDAutomation all have
built-in decoders that can read several different barcode symbologies.
There are a few low-priced scanners on the market, but they require
complicated decoders. In the long run, after ordering and programming
a decoder, more time will be spent using the decoder than if ordering
a scanner with a built-in decoder. Most of the barcode
scanners sold
by IDAutomation receive their power from the PC keyboard or
USB
port so no external power supply is required. When a barcode is
scanned, the data is sent to the PC as if typed on the keyboard.
To learn more about scanning barcodes, review
how to scan barcode
data into applications. Most barcode scanners can read common linear symbologies such as Code 39, UPC, EAN, Code 128 and Codabar by default. Some scanner manufacturers’ ship new barcode scanners with most symbologies disabled, therefore, if a particular barcode cannot be read, make sure it is enabled in the scanner's firmware. Not all scanners read barcodes that are printed at small X dimensions (the x dimension is the width of the narrow bar in the code,) so it is advisable to check the barcode scanner manual to make sure the scanner can read the small X dimensions. The low-priced IDAutomation Plug 'n Play USB Barcode Scanner performs like a laser scanner and reads very small barcodes. Barcodes of 4 to 32 mils in size and up to 4.2" in width are easily read from a distance of 4 to 8 inches with this scanner.
Many situations may exist where the space a barcode occupies becomes a concern. The barcodes below are all encoding the same data of "BARCODE12345678" with the same narrow bar width or X dimension of .03CM or 12 mils. When creating small barcodes, the scanner must also be able to dependably read them. Some barcode scanners also read different symbologies better at different sizes. For example, the Symbol Laser Barcode Scanner dependably reads the Code 39 Barcode Font when printed as small as 6 points, but only reads the Code 128 Barcode Font when printed at 8 points. However, the IDAutomation Plug 'n Play USB Barcode Scanner reads both Code 128 and Code 39 at 6 points and above. The barcodes below may be printed from IDAutomation’s Symbology Test Sheet for testing purposes.
As seen in the examples above, the Data Matrix barcode is the most compact of the symbologies evaluated. However, it requires a 2D Barcode Imager or Image Reader to read the symbol. Several Imagers can easily read small symbols, such as the Hand-Held Products Barcode Imager which can read Data Matrix barcodes printed with the Data Matrix Font as small as 2.5 points, which is an X dimension of about .02CM or 8 mils. Data Matrix is also one of the most accurate barcode symbologies.
The accuracy and amount of misreads of several different barcode symbologies were evaluated in a study at Ohio University Center for Automatic Identification. Studies indicate that a well-trained data entry operator will usually make a data entry error once every 300 keystrokes. Therefore, implementing even the least accurate barcode symbology is a huge step forward to increasing production and reducing data entry errors.
Specifications are provided by many types of barcode implementations.
In some cases, the specifications of the barcode sizing parameters
are given in inches, but need to be calculated in CM (centimeters)
in the barcode tool. To convert inches to CM, multiply the value
in inches by 2.54. To convert mils to CM, multiply the MILS (1 mil
equals .001 inches) value by .00254.
More information about barcoding and "Frequently Asked Questions" (FAQ) may be obtained from these sources:
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