A barcode scanner is designed to read printed barcodes or matrix codes. These devices consist of a light source, a lens, and a light sensor that translates optical impulses into electrical impulses. Barcodes, also known as universal product codes (UPCs), are machine-readable representations of data composed of dark and light bars. These bars represent a set of data, often a series of numbers. Barcode printers create these codes on labels or other visible surfaces.
Source: Taltech.com
The Barcode Reading Process
Barcode reading involves detecting the code and converting it into a digital representation. The most common method uses a light source directed at one section of the code at a time. A light sensor then detects the reflected light. Dark areas reflect less light than lighter areas. The sensor detects this difference and transmits it to a computer. The thickness and spacing of the dark and light areas determine the code itself. Basic barcode scanners utilize a single LED light and a light sensor. In this case, the user needs to swipe the scanner directly over the code.
Types of Barcode Scanners
A barcode scanner system typically includes a scanner, a decoder (either built-in or external), and a cable connecting the reader to a computer. The scanner captures and translates the barcode into numbers and/or letters. The software application on the computer then analyzes this data.
Several types of barcode scanners exist, including:
Stationary Barcode Scanners
Stationary scanners are placed on a counter or stand, requiring the code to be passed in front of the scanner.
Handheld or Gun-Type Scanners
These scanners can be either non-contact or close-contact. They typically use a focused beam of light to read the barcode. Also known as charge-coupled device (CCD) scanners, these are commonly used in retail settings because they require multiple readings to minimize errors.
Image Scanners
Image scanners are more advanced barcode scanners. Also known as camera readers, they use a small video camera to capture an image of the barcode. Sophisticated digital image processing techniques then decode the barcode. Advantages of image scanners include a longer scanning range (3 to 9 inches) and a lower cost compared to laser scanners.
Laser Scanners
Laser scanners can be handheld or stationary. They employ a system of mirrors and lenses to read barcodes from distances of 24 inches up to 30 feet. To reduce errors, laser scanners can perform up to 55 scans per second.
Conclusion
Barcode scanners play a crucial role in various industries, from retail and warehousing to healthcare and logistics. Understanding how these devices work and the different types available can help businesses choose the most suitable scanner for their specific needs. The technology continues to evolve, offering improved speed, accuracy, and versatility in data capture.
