Can't See Invisible Text? Your Cell Phone Can!

Toss out that bottle of invisible ink! Fujitsu is developing a technology that would allow for hidden messages to be printed within images printed on paper. The information could then only be decoded by a mobile phone or digital camera.

The technology works by taking advantage of the human eye's issues with the color yellow (bet you didn't know that). The yellow hue in the image could be manipulated to hide messages or some other data. To the naked eye, the image would look completely normal. When viewed with a specially enhanced digital camera or cell phone, however, the digitized cat would be out of the bag.

Fujitsu believes this new technology will work well in publishing, particularly with marketing ventures. Companies could easily use the technique to hide coupons for store discounts or access codes for special Web-only features--like free MP3 downloads.