First barcoding website from Romania!
Home | About Us | Solutions | Tutorials | Barcode Education | Biometric Education | Contact Us
Barcode Education » CCD Scanners

Of the two "non-contact" technologies (CCD and laser), CCD scanners are generally the lower cost.

CCDs use similar technology to that used in modern video cameras; they "scan" the bar code by registering a complete image of the code at once. CCD scanners are usually characterised by their wide heads and the way that they appear to illuminate the bar code in (usually red) light. You have probably seen these scanners used at check-outs in places such as DIY stores.

Although technically a non-contact technology, most CCD scanners have a depth of field, i.e. reading distance, of only one or two centimetres. Recent advances in optics though are now enabling some CCDs to work at longer distances, in some cases five centimetres or more. Generally, CCD scanning remains a close proximity reading technology.

CCD scanners can come with a variety of output and interface types depending on the individual model and manufacturer. Because CCD scanners already contain a built in microprocessor, the output is usually in a format that has already been decoded. Common output types are RS232 serial, TTL serial or keyboard wedge interface.

Apart from the need for close proximity, the only real drawback to CCD scanners is the need to match the maximum reading width of the scanner head to the bar codes to be read. Hence a CCD scanner with a maximum head and reading width of 60mm cannot read a bar code that is 70mm wide. Generally the widest head width for regular style CCD scanners is around 80mm.

It would seem logical therefore to always select the maximum head width scanner available. However, there is sometimes a very marginal trade off between greater width of CCD head and first time read rate, narrower heads sometimes having a slight performance advantage. Hence care should be taken in selecting a CCD scanner with the optimum head width. For much larger bar codes it is usually necessary to go up to laser scanners. One further limitation concerns curved surfaces: while CCD scanners can cope with modest curvature much better than a wand can, CCD readers are not usually designed to cope with the optical effects of curvature.

CCD Scanners probably represent the best value for money option for close proximity scanners and a good number are sold as wand upgrades. If getting close to the code is not a problem and the throughput requirement is medium volume, then CCD scanners are a popular choice.

Privacy Policy | Terms of Use Copyright © Rosistem