Fingernails Store Data
Japanese scientists have demonstrated that data can be written into and read from a human fingernail through the use of a laser. Dot patterns were written into a fingernail by striking it with a laser that ionized molecules and caused a miniature explosion that decomposed the keratin protein molecules in the targeted areas. These areas can be read thanks to their ability to absorb and emit light at a higher rate than the untouched fingernail material.
Three layers of dots were recorded and read at 40, 60, and 80 microns below the surface of the nail; the dots can be read using an optical microscope because they are visible in blue light. The dots are small enough to allow 2 GB of data to be written per cubic centimeter of fingernail, which means 5 MB could be stored within a fingernail recording area of 5 millimeters by 5 millimeters by one-tenth of a millimeter deep.
The proof-of-concept samples were still readable 172 days after recording, which is probably the practical limit of fingernail storage since a nail has grown enough to be replaced after six months.
University of Tokushima professor Yoshio Hayasaki says the technique could be applied to personal authentication, and dovetail with biometric authentication such as vein patterns and fingerprints. He believes the technique could be practical within a few years, once a safe, cheap method for writing data is found.
Abstracted by the National Law Enforcement and Corrections Technology Center(NLECTC) from Technology Research News (08/03/05); Patch, Kimberly .
