Author: POS Supply   Date Posted:7 October 2014 

Barcodes: 1D vs. 2D — Differences and Advantages

June 26, 2014 marked the 40th anniversary of retail barcode scanning. On that day in 1974, the first barcode scanner was put to use in a supermarket in Troy, Ohio, USA.

The need for an automated system of product identification has long been recognized. In 1932, a man named Wallace Flint proposed using computer punch cards in an automated checkout system. In 1952, a patent was issued to Bernard Silver and Norman J. Woodland for a bulls-eye-style code for identifying items. Years later, several trade associations of the grocery industry pooled their resources to support the creation of a universal product code (UPC) they could all use.

Proposals were submitted by a number of corporate heavyweights like IBM, Pitney Bowes-Alpex, RCA, Scanner Inc., Dymo Industries, Litton-Zellweger, Plessey-Anker, and Singer. The final, winning design gave the world the 1D barcode we now know so well. It consists of several vertical lines of varying thickness and spacing which represent a numeral sequence.

Standard UPC codes with a simulated laser scan. Image: courtesy

This is considered 1-dimensional, because it requires only a linear scan horizontally across the various vertical lines.

2D Barcode Labels and Scanners
The 1D barcode is rather limited in the amount of information it can store. It relies quite heavily on a corresponding, external database for product description, specifications, price, cost and other related information.

Not only that, the number of products in the world has continued to increase. The UPC-A code can store up to one trillion unique values. That may have seemed like a lot in the 1970s, but not any more, especially in a global community with every country increasingly made high tech.

If one dimension (a straight line of scanned data) can hold one trillion unique values, imagine what two dimensions (a square or rectangle) can hold. And that's exactly what product labelling developers have done.

There are currently a number of 2D code formats available, including DataMatrix, QR code, PDF417 and CM. These no longer depend on an external database or a communications network in order to access information not included in the 1D codes. In other words, all of the database information could be stored in the barcode itself.






QR code sample. Square only.


PDF417 code sample. Any rectangle.


PDF417 code compared to CM code sample of the same 2,000 numbers. Scale: 5.2:1






Sample barcodes courtesy


Sample codes courtesy

A 2D barcode must be scanned in two directions in order to cover the entire area. Fortunately, the 2D barcode scanners at POS Supply can scan both 2D and 1D barcodes. You don't need two kinds of barcode scanners. Thank goodness for that.

Another advantage of 2D barcodes is the ability to store more than merely numbers and English. The CM format is especially suited to store pictures, voice, Chinese characters and other binary information. Both QR and PDF417 can store text, small images and symbols. In practice, PDF417 typically takes four times (4x) the space of a QR or DataMatrix code block holding the same amount of information.

Scanners stocked at POS Supply come in a number of 1D and 2D varieties: handheld, cordless handheld, desktop and industrial.

Safety Concerns
Some have asked if the lasers used in scanners are dangerous. All barcode scanners use a Class II laser which is safe to eyes and other parts of your body.

One potential risk for the QR format involves malicious code. Thankfully, this should never be an issue inside of a store with products that your employees have labelled. But individuals scanning QR codes out of magazines, flyers and posters with smartphones have found their personal data compromised. For instance, URLs embedded in QR code can include Javascript which can perform harmful actions to exploit vulnerabilities in the application being used. Your own barcodes, of course, won't include such things, because your employees will be the ones who create them.
There you have it. A painless description of the differences between 1D and 2D barcodes. You're in good hands with POS Supply.