Patent ID: 8462603

Claim:
A device for recording/reading information on a multilayer optical disc, comprising an optical disc positioning system, a source of radiation with wavelength λ 1 , a focusing system arranged such that its optical axis is perpendicular to the flat surface of the multilayer optical disc, a source of radiation with wavelength λ 2 , an illumination system arranged such that its optical axis is perpendicular to the optical axis of the focusing system, focusing system positioning means, a spectrum splitter located between the source of radiation with wavelength λ 1 and the focusing system, as well as a optical sensor optically coupled with the focusing system via the spectrum splitter, and a control unit electrically coupled with the sources of radiation with wavelengths λ 1 and λ 2 , and the optical sensor, wherein the source of radiation with wavelength λ 2 is designed as an array of laser diodes whose optical axes are parallel and lie in the same plane, while the illumination system comprises components serially arranged along the optical axis, said components including a cylindrical lens which is arranged such that the generatrix of its cylindrical surface is parallel to the plane in which the p-n junctions of the laser diodes are located, a focusing lens and a stabilizing circuit comprising a beam splitter that is placed between the focusing lens and the cylindrical lens, a second optical sensor optically coupled with the focusing lens via the beam splitter, and a stabilizer coupled with the focusing lens, said stabilizer and second optical sensor being electrically connected to the control unit.