With cellphones being ubiquitous in Japan, one big problem is how to get cellphone users to access web sites that may be advertised in print. Fortunately, this problem has been solved by Nippon Denso of Japan in 1994, when they came up with Quick Response Barcodes, or QR Codes as they are commonly known as. This article will look at what they are and how these codes are used in Japan.

What are QR Codes?

QR Codes are basically two-dimensional barcodes that can encode either English or Japanese text. The text can be flagged as one of an email address, a web address, plain text or phone number. When printed out, they are large squares with lots of little squares inside them, conventionally black squares on white text, but that is just to maximize the contrast, so sometimes they can be found in other colors.

How do you use QR Codes?

To read in the data, all that is necessary is to select the QR Code reading function from your cell phone's menus (all new phones in Japan can read QR Codes) point your mobile phone's camera at the QR Code, and take a photo. One thing I've noticed is that many people try their hardest to fill the viewfinder with the image, a task made harder by shadows being cast by the cell phone, and ensure the image is properly aligned. However, this is usually unnecessary, as the average cell phone has a camera with sufficient resolution and software with sufficient smarts – QR Codes have locating marks to help software to orient the image correctly. Just poking the mobile phone in the general direction of the QR Code will suffice the vast majority of the time.

What are QR Codes used for?

The most common usage of these codes are in advertisements, of course. The two main types are for access to a web site for further details about the product advertised, or, especially in relation to restaurant advertising, access to a discount coupon. The two main ways of getting this information are first and most obviously a direct URL, but the other way is to encode an email address within the QR Code. When an empty message is sent to this address, a reply is sent containing a URL to access. From the advertiser's point of view, the user's email address has now been captured, so this is a very valuable way to build up a mailing list of potential customers.

Other interesting QR Codes uses:

These codes appear not just as small images in advertisements, but once or twice I have seen them hanging from new tower blocks being built. There QR Codes are at least 10 meters square, and presumably they can be captured on most standard phones. There is also a game called QR-Kill , where everyone wears a QR Code on their clothes and others hunt them and "kill" their targets by shooting their code, which sends an SMS to the victim. A third practical use is on information web sites accessed from computer, such as mapping or route planning software. A QR Code containing a URL that points to the data is displayed on the computer screen, so the user can capture that on their cell phone.

With research showing that over 60% of cell phone users use QR Codes , it is certainly only a matter of time before they reach the same levels of popularity in the west.