FAQ# 1067:

What is the difference between laser barcode scanners and imagers, also known as CCD barcode scanners?


What is the difference between laser barcode scanners and imagers, also known as CCD barcode scanners?


All barcode scanners function in fundamentally the same manner: The scanner produces a beam of light, which it uses to detect the width of the bars in a barcode and the spaces between them. The difference between laser scanners and imagers is in how they detect these bars.


A laser scanner sends out a thin beam of light at the barcode. This beam of light is reflected off the barcode differently depending upon the color of the surface the beam hits. Recall that white is the result of all colors of light being reflected, and black is the result of all colors being absorbed. Of course, due to several factors, even the black on a barcode will reflect back some light. Still, the laser scanner is able to detect the width of the bars in the barcode by sensing the amount of light being reflected by the surface on which the barcode is printed.


An imager (or CCD barcode scanner), however, functions in a manner similar to a digital camera. The scanning element in a linear imager barcode scanner (see our FAQ on the difference between 1D and 2D barcodes for more information about linear scanners) is actually a row of hundreds or thousands of small light sensors, each of which measures ambient light. When a linear imager detects a barcode in its field of view, these sensors take a reading of the light, effectively taking a picture of the barcode.


(How do 2D imagers work? They work in much the same way as linear imagers, except that they utilize an array of light sensors, rather than a single row.)


If you're particularly savvy, you may be asking why it is that linear imagers have light beams to begin with. After all, your digital camera works just fine without a flash, most of the time. Well, "most of the time" is key, here: The light beam from a linear imager helps illuminate barcodes in situations where they otherwise might not be readable. And the light beam serves another important purpose: Without it, you would be unable to correctly aim your barcode scanner.

Need Help? We have answers to all your Tech Support needs!
This question is associated with categories:
Barcode Scanner With the right barcode scanner, you can speed data collection and eliminate data entry errors in any industry. From hand-held to presentation, POSGuys has a variety to choose from. Let us help you find the best scanner for your business.