Another step toward the holodeck

Japanese engineers have developed holograms that respond - or appear to respond - to human touch. Using ultrasound to track the movement of the human hand involved, their system makes the hologram respond as though it were a physical object being handled directly. The creators say they can visualize numerous practical applications in letting humans operate cotnrols without actually having to be in contact with their machines. Star Trek fans, of course, will see it as one small step toward the series' holodeck. The holodeck is an extremely difficult, maybe impossible, technolgy, but you never know what those clever Earthers will come up with.