Ready? Here comes the science bit....
How is a Bokode coded?
As with a traditional Barcode, the pattern in a Bokode is a tiled series of two dimensional Data Matrix codes consisting of black and white cells or modules aranged in either a rectangular or square pattern. On a Bokode the patterns can be shrunk to a tiny size so that a large amount of information can be stored in a relatively small area. This gives Bokodes a large advantage over traditional barcodes in both in the amount of information they can transfer and, because this inforamtion can be read from several meters away, the contexts in which they can be used.
How can you read a Bokode from several meters away?
The lens over the Bokode printed pattern causes the rays of light leaving the pattern to collimate and become parallel to each other. The view that the camera has is several hundred pixels in diameter allowing the camera to see a magnified view of the code containing thousands of bits of data. Theoretically, a Bokode could be read from up to 60m distance.
Light emitted from the Bokode is magnified
Does the camera see the whole Bokode?
No, because of the spread caused by the lens, the camera only sees a small portion of the pattern. However, the Bokode pattern encodes not only the identification but also information that allows the camera to identify its position relative to the Bokode. Each block of code contains information on it's identity and it's relative position in the matrix.
Virtual objects overlaid on the scene
This can come in very handy for Augmented reality applications and Motion Capture. For Augmented reality, a scene is captured with two cameras, one focussed at infinity and the other on the object. The positional information is recovered from the Bokode and that information can be used to overlay virual objects into the infocus scene as in the image above. In a Motion Capture context, for example in a computer generated movie scene where movement is normally captured using coloured dots or balls attached to the object being filmed, the dots can be replaced with Bokodes capable of transmitting positional information to within a tenth of a degree, far more accurate than current motion capture systems.
A comparison of tradtional positional techniqes and the Bokode
Unlike with traditional AR tags where geometric distortion is used to identify camera position, Bokodes contain the information required for the camera to establish it's relative position. Resulting angle and positional estimates are far more accurate.
How will passive Bokodes work?
In the case of a passive Bokode with no LED and power source, the camera flash will be used to make visible the Bokode pattern by illuminating a reflector behind the pattern.
What else can they be used for?
There are mutliple possibilites for this technology, wherever it's an advantage to transfer information visually Bokodes can be used. Interaction with a visual presentation would be useful in educational and business contexts. Mulptiple players can engage in games using small handheld receivers to interact with the displayed game image. Products in shops can be compared for price differences or the nutrional value of a food displayed and specific books found in libraries just by pointing your scanner at the shelves.
Testing a Bokode!
Testing the Bokode concept using a red LED and tiny SparkFun logos printed at 5080 DPI on a transparency. Each SparkFun logo is only 0.52 x 0.78 mm!