Remember Singaravelan Movie(Tamil) where Kamal hasan taps on Thai Amma’s Hand and says
“Ding Ding Ding Bummm” --- People have used this to found a new touch screen technology called Skinput ( I think People in Microsoft Research Lab has been inspired from this movie lolz (Tamil Lollu))
This future technology is developed in collaboration with Microsoft and Carnegie Mellon University. The system works with acoustic waves i.e. it has the ability to pick the Ultra low frequency sound also it can have a pico projector to display the User Interface on the Hand
When ever we tap on our Arms or Hand we get sound, people have captured that sound to recognize which part of the hand you have tapped based on the Bone density, Mass and size, distance between the joints and also filtering from soft tissues this makes each skin area sound as unique one or the system can easily identify the “Skin Button”
If you normally tap the hand we won’t feel any difference but when seen in a slow motion each tapping produce a transverse wave. This technology is actually harnessing those bio acoustic waves for processing.
The system beams a keyboard or menu onto the user's forearm and hand from a projector mounted in an armband. The acoustic detector which is also mounted in the armband will calculate which area the user has touched the skin.
The system could use wireless technology like Bluetooth to transmit commands to many types of device including phones, iPods and even PCs , TV etc
In Picture : Chris Harrison ( Researcher, Man behind the Technology)
Currently the research claims to have achieved a 95.5% accuracy in tapping, the pictures shows the different tapping areas of the hand
The Tap area gives us minimum 10 skin button which is enough to control any Phones or Personal Media player (PMP) like iPods, MP3 players,
The above picture shows the User can regular User interface with back button or like this they have developed scrolling option in hand, if you tap on top of the hand it will scroll up, if you tap near hand elbow joint it will scroll down. To go back to previous screen you need to pinch or touch your thumb finger with any other finger.
The Touch screen technology is surely different one.
So far this is a Research Project has some cool applications. The below picture shows user controlling Tetris game in the computer by tapping his finger
This below picture is showing a tetris game projected on your hand using pico projector
Source : New scientist
Watch this video
so the Future is your hand saying is becoming true :)