What is a Barcode Scanner?

A barcode scanner in its most basic form is an electronic device for reading printed barcodes. It consists of four parts: a light source to illuminate to barcode, a lens, a photo conductor to translate optical impulses into electrical impulses, and decoder. The decoder, which can be either internal or external, analyzes the barcode’s image data provided by the photo conductor and sends the barcode’s content to the scanner’s output port.

Barcode scanners are everywhere, from the grocery store to the assembly line. They can be found any place barcodes are used. Just as there are a variety of environments in which barcode scanners are used, there are also many different types of barcode scanners.

Barcode scanners vary in form factor, interface, and scan engine, and they all have specific applications and environments for which they are better suited. While scanner form factor and interface are important, nothing differentiates one scanner from another like the scan engine.

There are four different types of scan engines that a barcode scanner may have and they are: laser scanners, linear imagers, multi-line laser scanners, and 2D/area imagers.

Laser Scanners

Laser scanners are the most popular type of barcode scan engines, as they have been around the longest. These scanners use a laser to read the difference in the spaces between the barcode’s vertical lines. The laser by itself is just a small dot; however, there are mirrors inside the scanner that toggle back and forth rapidly to produce the thin red laser line.

These scanners work well when precise scanning is necessary as the user can easily target the thin laser line. Laser barcode scanners are also ideal for scanning in environments with bright lights or if scanning barcodes at distances greater than 12”. Laser scan engines can only read 1D or linear barcodes and are seen in every scanning environment, especially retail.

Linear Imagers

Linear imagers, or charged coupled device (CCD) scan engines, like laser scanners, only read 1D barcodes, but unlike laser scanners, they don’t use lasers to read barcodes. As stated in their name, linear imagers use the image, or the picture, of the barcode to collect data.

These scanners are more durable than laser scanners as there are no moving parts. Linear imagers are great for scanning barcodes that are under a reflective surface, such as plastic wrap, or for reading barcodes that are poorly printed or damaged. Linear imagers are most often used in shipping and receiving.

Multi-Line Laser Scanners

Also know as omnidirectional scanners and retail barcode scanners, multi-line laser scan engines use multiple laser lines to scan barcodes no matter the orientation. Some multi-line laser scanners have up to 100 different scan lines making for a quick scan, without having to position the barcode in the right direction; one of the laser lines is sure to catch the barcode properly.

These scanners are almost always found in retail settings because of their fast hands-free scanning and the ability to be mounted in or on the checkout counter.

2D Scanners

2D barcodes are used for one reason: to encode more information. The only way to read a 2D barcode is with a 2D barcode scanner. Also known as area imagers, these scanners capture an image of the barcode to decode the data like linear imagers, but in a much larger area. They can read 1D and 2D barcodes omnidirectionally, meaning the barcodes turned in any direction.

2D barcode scanners are also capable of image or signature capture, and are a great way to future proof your business. These scanners are used in all scanning environments, but are most often found in manufacturing and warehousing.