Barcodes are progressing from 1D to 2D codes, so here’s a quick run-down of what these terms mean and what implications there are for the technology required to read them.
1D codes are the bar codes we are used to seeing on our grocery items. These have been around since 1974, would you believe (!) and are well established. They have been traditionally read with laser devices that scan a single line anywhere across the code, cutting the bars at 90 degrees and spanning the entire code to achieve a read. These codes are generally of a fixed length for retail use, but can have more data encoded for non-retail use. The downside is that the more data you encode, the longer the code gets. Not great when you have lots of data to encode…
2D codes are now being used as they allow the encoding of far greater amounts of data. These not only encode data in one dimension (across, as in 1D codes) but vertically too, creating square form-factor codes. You’ll see these used on shipping labels on packages from the big couriers, where your entire address can be encoded, as well as on the codes used with electronic boarding passes on your mobile phone for flights and train journeys.
These 2D barcodes can only be read by camera-based technology, or an ‘Imager‘ as they are now referred to. These actually take a picture of the code and the surrounding area. The cool thing about imagers is that they can read a code from an electronic display or TFT screen, where a laser barcode scanner can not.
Imagers are also able to decode 1D codes, so are backwards-compatible with existing barcode technology in the field.