6-hour compact discs

1993/06/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

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They have managed to access a single compact opera album from 5 to 6 hours! By changing the color of the laser beam that reads the discs, they will soon be able to enter ten times more information on the compact disc (CD). Currently the information cannot be compacted anymore due to the light scar that the laser creates on the disc. This stain depends on the wavelength of the light beam. The treatment of semiconductor lasers has allowed obtaining rays of lower wavelength.

Apart from the semiconductors of gallium arsenide commonly used in the laser, in the laboratories of CEA and CNRS of Grenoble semiconductors of cadmium and magnesium telururo have been used.