This is a short primer on bar code technology. Barcode technology is now widely used in supply chain operations and for asset management activities to automatically identify items. Barcodes were first used on railroad cars and first became commercially successful with the use of automated supermarket checkout systems. Over the years the types of barcodes have expanded from traditional 1-dimensional barcodes that contain a set of numbers or serial number to 2-dimensional barcodes that can contain multiple data elements.
Barcode Technology Alternatives. Besides barcodes, there are other types of Automatic Identification Data Capture (AIDC) technologies such as biometrics technologies and passive Radio Frequency ID (RFID) technologies. As the costs of these alternative AIDC technologies go down or where these technologies can fill specific needs, barcode technology may be superceded by other Auto ID technologies. On the other hand, barcode technology is cheap and simple. Barcode technology will continue to be a good choice for automatic ID solutions for a long time to come. The cost to implement a bar code is 0.5¢ (U.S.) or less versus other auto ID technologies cost more. Other auto ID technologies such as passive RFID are becoming more cost-competitive as they continue to drop in cost.
Bar Code Described. Wikipedia defines bar codes as follows:
“A barcode is an optical machine-readable representation of data, which shows certain data on certain products. Originally, barcodes 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. Barcodes can be read by optical scanners called barcode readers, or scanned from an image by special software.”
Bar Code Structure. Traditionally bar codes have consisted of a label with a series of vertical lines (bars) and spaces. These bars and spaces are called elements. When a bar code reader scans the different size bar and spaces on a barcode, the reflective light from the barcode is converted into electronic signals. From there, the barcode automation translates the electronic signals into a series of characters such as a serial number or product ID. Over time bar codes have evolved into non-linear formats such as 2-dimensional formats, but basically use the same methodology of reflective light and electronic signals. See Bar Code Structure for more details.
Types of Bar Codes. There are many types of bar code formats to include UPC, EAN, GS1 DataBar, ITF Interleaved 2 of 5, Code 93, Code 128, Code 39, PDF417, Data Matrix and MaxiCode. Why are there so many different types of bar codes? One reason is that many industries and vertical markets standardized on a set of bar code standards many years ago. In many cases, a particular bar code standard still fulfills a need and there is no reason to change to a new format. In other cases, an industry or market has evolved its bar code standards. For example, many industries and companies are now using 2-D bar code standards such as PDF417 because the bar code contains a lot more data than just a serial number or product ID. See Worth Data’s bar code primer for more information on bar code types and recommendations.
Bar Code Reader Technology. A bar code reader or scanner is needed to reflect light over the bar code and read” the bar code. Additionally, the bar code reader must have a communications interface with the business computer that will subsequently use the bar code data. There are basically three types of bar code readers: fixed, portable batch, and portable RF. Below is a list of different types of bar code readers:
- USB Keyboard Interface Bar Code Readers. This is a fixed bar code reader where the bar code reader is connected to a computer via an USB port.
- Personal Computer Keyboard Wedge Readers. This fixed bar code reader physically “wedges” itself between the keyboard and the computer where the wedge reader emulates keyboard input.
- Serial Bar Code Readers. This fixed bar code reader transmits ASCII data to the computer using a serial connection.
- Portable Readers. This is usually a low-cost portable batch bar code reader. This handheld device consists of a battery operated readers with data storage and physical connection for batch uploading data to the computer.
- Radio Frequency Readers • RF Terminals. Portable RF Readers are like on-line terminals, but wireless. The user can roam around his local facility scanning and keying data and getting a response from the computer with each entry.
- Types of Scanner Technologies. There are several ways that a bar code scanner can scan bar codes. See Worth Data’s bar code primer for more information on CCD Bar Code Scanners, Wand Scanners, Slot Badge Scanners, and Laser Scanners.
Bar Code Technology Printing. Deciding how you want to print bar codes as well as the day-to-day printing of bar codes is as much of an art as a science. Key considerations include environment (hot, cold, humidity, water, and so on) and balancing the costs of label materials, label printers, operational procedures, and scanner technology with the effectiveness of the scanners reading the barcode error free. Businesses have many choices in creating barcodes to include having the label manufacturer create the barcode, using regular business printers, or using specialized thermal transfer printers. See Worth Data’s bar code primer for more information on bar code printing and recommendations.
Bar Code Applications. Bar code technology works with bar code applications to reduce and eliminate data entry and automate many operational processes in businesses and supply chains. Example bar code applications include: Assembly Checking, Fixed Asset Inventory Control, Job Costing and Tracking, Library Automation, Meter Reading, Point of Sale, Records Management, Remittance Processing, Stock Taking, Time and Attendance, Warehouse Picking, Warehouse Put-Aways, Warranty and Service Tracking, Work-In-Process Inventory Tracking, Rental Car Check in and Billing, Receiving, and Shipping to name a few. See Worth Data’s bar code primer for more information on descriptions of different bar code applications.
