Bar-Code Reader

What Is Bar-Code Reader

A barcode reader also called a price scanner or point-of-sale ( POS ) scanner, is a hand-held or stationary input device used to capture and read the information contained in a bar code. A barcode reader consists of a scanner, a decoder (either built-in or external), and a cable used to connect the reader with a computer.

How It Is Worked

A barcode reader works by directing a beam of light across the bar code and measuring the amount of light that is reflected back. (The dark bars on a barcode reflect less light than the white spaces between them.) The scanner converts the light energy into electrical energy, which is then converted into data by the decoder and forwarded to a computer.

Types Of Bar-Code Reader

There are five basic kinds of barcode readers -- pen wands, slot scanners, Charge-Couple Device ( CCD ) scanners,  image scanners, and laser scanners.

Pen Wands

A pen wand is the simplest barcode reader. It contains no moving parts and is known for its durability and low cost.

Slot Scanners

A slot scanner remains stationary and the item with the bar code on it is pulled by hand through the slot. Slot scanners are typically used to scan bar codes on identification cards.

Charge-Couple Device ( CCD ) Scanners

A CCD scanner has a better read-range than the pen wand and is often used in retail sales. Typically, a CCD scanner has a "gun" type interface and has to be held no more than one inch from the bar code. A disadvantage of the CCD scanner is that it cannot read a bar code that is wider than its input face.

Image Scanners

An image scanner, also called a camera reader, uses a small video camera to capture an image of the bar code and then uses sophisticated digital image processing techniques to decode the bar code. It can read a bar code from about 3 to 9 inches away and generally costs less than a laser scanner. 

Laser Scanners

A laser scanner, either hand-held or stationary, does not have to be close to the bar code to do its job. It uses a system of mirrors and lenses to allow the scanner to read the bar code regardless of orientation, and can easily read a bar code up to 24 inches away. To reduce the possibility of errors, laser scanning may perform up to 500 scans per second. Specialized long-range laser scanners are capable of reading a bar code up to 30 feet away.

Why We Use It

Although there is no law that you must have a barcode, most retailers and distributors will require you to have one for inventory and sales records purposes. If you are planning to sell your products in the retail market, you should register your product with GS1. GS1 is a global keeper of barcodes

More About Bar-Code Reader

A barcode reader merely captures and translates the barcode into numbers and/or letters, the data must be sent to a computer so that a software application can make sense of the data. Barcode scanners can be connected to a computer through a serial port, keyboard port, or an interface device called a wedge.