Chemical "Infofuses" Communicate Without Electricity

Al writes "Researchers at Harvard and Tufts University have developed a way to send coded messages without using electricity. David Walt, professor of chemistry at Tufts, and Harvard's George Whitesides have developed 'infofuses' that can transmit information simply by burning. The fuses — metallic salts depositing on a nitrocellulose strand — emit pulses of infrared and visible light of different colors whose sequence encodes information. They were developed in response to a call from the Defense Advanced Research Projects Agency for technologies to allow soldiers stranded without a power source to communicate. In the first demonstration of the idea, they used the infofuses to transmit the message look mom no electricity." Currently the researchers are "trying to figure out a way to dynamically encode a message on the fly in the field without specialized equipment."

Re:hand cranked flashlight

[Red Flayer]

Well, after I RTFA (sacrilege, I know), the point would seem to be data density. The signals are read by a CCD, not by a human interpreter, though I'm sure there is decent software out their for parsing morse code. It takes a while to send morse code signals if you're not in good practice, and the whole time you're sending the signal you're vulnerable. So the signal "fuse" has the advantage of transmitting an encoded message faster than most people using morse code could.

It's odd that the receiver is expected to have electricity, but not the sender... I really wonder about the utility if the electricity requirement is still there for one party.