28-08-2017, 10:58 AM
Nail storage is a method of writing data into a human fingernail with a pulsed laser. Fluorescence of the nail, when exposed to ultraviolet light (UV), increases at the points where the data are written. Data can be read from the fingernail using a microscope while irradiating the nail with UV energy. Femtosecond laser pulse processing offers a powerful tool to develop new high-capacity devices. Yoshio Hayasaki and his colleagues discovered that the data can be written on the human nail.
Recent experiments with Yoshio Hayasaki, from Tokushima University (Japan), have involved small regions of a single nail, approximately two millimeters square. A pulsed laser, at a wavelength of 800 nanometers (nm), is used to write the data into the nail. Each data bit is approximately 0.003 millimeters (mm) in diameter. The individual data bits are spaced 0.005 mm apart, in three layers at depths of 0.04, 0.06 and 0.08 mm within the nail.
Nail storage has a limited life because human nails grow outward. The average human nail is completely replaced by the body every six months, assuming the nail is cut short at regular intervals. Nail storage has been suggested as a biometric means of identification, and also for the storage of critical medical information for use in emergencies.
