DISPOSITIF D'ENREGISTREMENT ET DE LECTURE D'INFORMATION DANS DES PISTES D'INFORMATION D'UN PORTEUR D'ENREGISTREMENT OPTIQUE

摘要

An apparatus is described for writing and reading information tracks in an information surface of a record carrier by optical radiation. The apparatus comprises two diode lasers, one of which produces the write beam and the other a read beam. By means of polarization sensitive device the write spot and the read spot formed on the information layer are projected at a very small and stable distance from each other and the beams reflected by the information layer are spatially separated. The separated beams are routed to separate detectors with residual cross-talk between the beams being eliminated by wavelength-selective filters.